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comfyui-loop-mcp

It doesn't just drive ComfyUI — it runs the loop: submit → get_result → get_image (LOOK) → compare_images → loop_record, with the ratchet (best-so-far + ledger) held on disk

A loop-aware MCP server for your own ComfyUI. It doesn't just call the API — it runs the loop: build → run → look → critique → fix, until the output actually meets the brief.

A graph that runs with zero node_errors is valid, not correct. Mangled hands, a drifted background, a hard matte edge, a visible tile seam — none of that shows up in an error log. It only shows up in the pixels. So every tool description, every tool response, and the server's own instructions push the model to look before it declares a graph done.

The part nobody else has: the ratchet is a tool, not a suggestion. Most agent tooling drives ComfyUI. This one manages the loop — a long loop gets its context compacted, and the moment that happens a remembered "best-so-far" is gone: the ratchet silently stops ratcheting, the model retries changes it already rejected, and it can hand you a regression as the final answer. So the best graph and the ledger live on disk, not in the model's memory. Reverting is a tool call, not an act of recall.

loop_start ─▶ submit ─▶ get_result ─▶ get_image ─▶ compare_images ─▶ loop_record ─┐
     ▲                                   (LOOK)      (what moved?)    (ratchet)   │
     └───────────────────  revert to best, try something else  ◀─────────────────┘
                                                          ↓ can't name a defect?
                                           loop_finish + loop_report → sign-off

The method ships with the server. The loop prompt and the Claude Code skill live in comfy_loop/docs/ and are packaged into the wheel, so comfy_loop / comfy_skill / comfy_install serve them verbatim from wherever the server is installed — one source, nothing to keep in sync. (They started life in comfyui-llm-onboarding-prompt, which is no longer maintained; this repo is where they're kept now.)


How it compares to Comfy's own MCP servers

ComfyUI ships two official servers, and this is a third thing built alongside them — independently, and from the other end of the problem.

Comfy-Org/comfy-mcp (first commit 2026-07-01, one day after this one, though it was public first) drives a local ComfyUI through comfy-cli: every tool shells out to the comfy binary and parses its JSON envelope. Comfy Cloud MCP (https://cloud.comfy.org/mcp) is a remote HTTP server that runs the graph on Comfy's GPUs. Both are built and maintained by the ComfyUI team.

This one speaks HTTP to /prompt and /object_info directly — no CLI, no account, nothing to install beyond httpx — and spends its surface area on the half of the job that starts after a graph runs.

The actual difference

Their local server treats the ComfyUI install as the thing to manage: launch it, stop it, roll it to another version, sign in, spend credits on hosted partner models, tail its logs, keep the packs updated. That is a genuinely bigger surface than this repo has, and it is the surface a platform vendor is best placed to own — it moves whenever ComfyUI, comfy-cli or the partner APIs move. If what you need is drive and maintain my install, use theirs.

This one treats the output as the thing to manage — because that is the part we were on the hook for. It came out of Alienrobot's own production work, where a graph that runs is the start of the job, not the end of it. Nothing here launches a process or spends a credit. Instead: return the pixels to the model, diff two passes into an image where drift can't hide, score the thing the brief actually demands, and hold the best-so-far on disk so a compacted context can't lose it. That's the part no one else has — not because it's hard to call /view, but because "make the agent look, and stop it building on a regression" is a discipline, not an endpoint.

this repo

Comfy-Org/comfy-mcp

Talks to ComfyUI via

its HTTP API (/prompt, /object_info, /view)

comfy-cli subprocesses (comfy … --json)

Extra dependency

none (httpx, pillow)

comfy-cli ≥ 1.14, and an install it knows about

Sees a ComfyUI you didn't install

yes — anything the URL reaches, incl. a box you have no shell on

partially; some tools are local-only by construction

Look at the result

get_image, get_video_frame — pixels back to the model

fetch_outputs(inline_images=True)

Judge the result

compare_images (difference mode), image_diff_stats, measure_image (tile-seam / sharpness), video_temporal_stats

Keep the best one

loop_*: ratchet + ledger on disk, revert is a tool call

Explore a parameter

loop_sweep — one input, N values, one call, recorded in the run

vary_workflow — cross-product of slot values into files

Pre-flight a graph

check_workflow — missing packs, missing model FILES, unset required inputs, dead wires, no output node, in one answer

validate_workflow + workflow_deps + template local_check

Subgraph templates

expanded and rewired (promoted widgets kept)

expanded client-side

Token cost of discovery

compact node notation (93% off object_info, 987 nodes); FlowZip graphs ~72% off litegraph

not a stated goal

Install what's missing

ComfyUI-Manager: install_node_pack, install_model, restart_comfyui, update_comfyui

registry install_node, download_model (backgrounded, cancellable), full update/version-switch

Zero to running

the agent does it: comfy_install is a prompt filled in from this machine (existing install, this Python, this box's accelerator), and any failed call returns the start/install commands

tells you to run comfy install in a terminal; launch_comfyui / stop_comfyui / switch_comfyui_version drive an install that already exists

Run the ComfyUI process

no — restart only (via Manager); the agent owns the shell

comfy-cli subprocesses, so yes

Hosted/partner models, accounts, credits

no, deliberately

auth_login, partner_generate, spend-consent gates

Job control

submit_workflow, job_status, cancel_job, get_queue, interrupt

one job tool: status / wait / watch / cancel / queue

MCP surface

43 tools + 2 prompts + 3 resources

39 tools

Size / licence

~3,700 lines, MIT

~16,000 lines, AGPL-3.0-or-later or commercial

Built by

Alienrobot — built for, and used in, our own VFX/generative work

the ComfyUI team, alongside the platform itself

Scope of the commitment

the loop: discovery, conversion, and judging the output

the whole install: lifecycle, accounts, partner APIs, packs

Which to use

  • No GPUCloud MCP. Nothing local competes with hardware you don't have.

  • "Install it, run it, keep it working"Comfy-Org/comfy-mcp. Lifecycle, partner models, background downloads, version pinning.

  • "The first result runs, and a trained eye rejects it"this one. Six fingers, a drifted background, a hard matte edge, a visible tile seam, a clip that boils. That's a loop, and this is a server built entirely around it.

They compose: nothing stops you running both, and the tool names don't clash. (The package names did — this one was comfy-mcp too, briefly, which is a losing argument to have with the people who own the ComfyUI namespace. Hence comfyui-loop-mcp; the import package is comfy_loop, and both can be installed side by side.)

What we're not going to add

Absorbing a competitor's feature list wholesale is how you end up with two mediocre tools. What's here from theirs is what a loop needs — pre-flight, job status, log tailing, VRAM headroom, updates. What stays out, on purpose:

  • Accounts, credits, hosted partner models. The pitch is "nothing leaves your machine, no signup, no meter." A credit gate contradicts it. If you want Kling or Veo, their server does it properly, with consent gates this repo has no reason to reinvent.

  • Launching and stopping the ComfyUI process. An HTTP client cannot start a server that isn't running, and pointing this at a box you have no shell on is a supported case, not an edge one. restart_comfyui (via Manager) is the honest limit — but "can't" is not the same as "won't help": the agent usually does have a shell, so an unreachable server returns the install/start commands for this machine and expects the agent to run them. Neither this server nor Comfy-Org's installs ComfyUI for you (theirs points you at comfy install in a terminal); the difference is that here the instructions come back through the tool call, aimed at whoever can act on them.

  • Workflow save / share / reproduce as a service. save_workflow hands you a round-trip-verified file. Where it lives after that is your business.

Related MCP server: ComfyPilot

The three MCP primitives, mapped to the loop

Primitive

What it exposes

Loop step

Tools

check_comfyui, list_nodes, get_node, list_models, search_models, search_templates, get_template

Discover, don't guess

find_missing_nodes, install_node_pack, install_model, restart_comfyui, update_comfyui

Extend (install what a template needs)

check_workflow

Verify before the GPU is involved

inflate_workflow, flowzip_to_api

Compress (token-efficient graphs)

template_slots, run_template

Run a known-good template with overrides (no graph in context)

upload_image, submit_workflow

Build → Run

get_result, get_image (returns the actual image)

Look

loop_start, loop_record, loop_sweep, loop_best, loop_ledger, loop_finish, loop_report

Ratchet + ledger, on disk

system_stats, get_queue, job_status, cancel_job, interrupt, free_vram, comfyui_logs

Control

Prompts

comfy_loop (full method), comfy_skill (compact), comfy_install (bootstrap)

The whole discipline, one command

Resources

comfyui://object_info (live), comfyui://loop-method, comfyui://skill

Truth + docs

Three things make it loop-aware rather than a plain API wrapper:

  1. get_image returns the rendered output to the model — that's the step that makes "look" real. The model literally sees the pixels.

  2. Tool responses push the loop. submit_workflow on success says "valid, not correct — now LOOK"; on a rejection it says "not an iteration — fix the named node and re-submit." get_result ends with a directive: "do not stop here — LOOK, then change one parameter or declare the brief met."

  3. The server instructions carry a prefer-looping policy (see below) that the client injects at connect time.

The prefer-looping policy (server instructions)

At handshake the server tells the agent when to loop and when not to:

  • ALWAYS discover from the live API before writing JSON; validate by executing; node_errors are not iterations — fix and re-submit.

  • PREFER LOOPING whenever a trained eye could reject the output — composition/ count, likeness, matte/edge quality, upscale/restore, relight, texture seams, video temporal stability, "make it look right."

  • RATCHET — hold a best-so-far; keep a change only if it beats it, else revert and try something different; pivot param → wiring → model on plateau. Gate on an objective test only where the brief has one; judge by eye otherwise.

  • SKIP the loop only for mechanical tasks (format conversion, a pure API query, or when the user explicitly wants just a runnable graph).

  • When unsure, do at least one look-and-critique pass before declaring done.

The ratchet/ledger/pivot are adapted from Karpathy's AutoResearch loop, tuned for subjective image work (objective gate only where one exists; a human sign-off checkpoint instead of running forever). These policy lines live in the server instructions + tool responses; the full method is in the comfy_loop prompt, which serves the repo's loop doc verbatim.

MCP can't force behavior — it exposes capabilities and guidance. This makes looping the strong, well-scoped default the agent is repeatedly told to prefer. For a hard guarantee in Claude Code, install the same text as an always-on skill:

mkdir -p ~/.claude/skills/comfyui-workflows
cp comfy_loop/docs/SKILL.md ~/.claude/skills/comfyui-workflows/

Skill = always-on discipline, MCP = the tools it drives. It's the same file the comfy_skill prompt serves, so they can't disagree — and it defers to comfy_install for bootstrapping rather than carrying its own stale recipe.


Tool reference

Discover

Tool

Args

Returns

check_comfyui

Loop step 0, and a real preflight. When nothing answers it returns what to do about it, specific to this machine — start the install it found, create one, or open the tunnel for a remote URL (see Troubleshooting). When it does answer, it still names what stands between here and a working render: torch running on the CPU (every render works, ~50x slower, nothing reports an error), no weights on disk (a fully functional ComfyUI that can render nothing), no ComfyUI-Manager (with the two commands to fix it, since restart_comfyui is itself a Manager route). Otherwise: node count, ComfyUI/torch versions, per-device VRAM free vs total, whether ComfyUI-Manager is present (no Manager = no installs, no restart), and whether the queue is already busy — or a clear "not reachable".

list_nodes

keyword=""

Nodes whose class name or display name matches (a strict superset of the skill's class-only search). Omit keyword for the count.

get_node

class_name, verbose=False

One node's interface as compact @Name +req:T ?opt:T -out:T (~90% fewer tokens); verbose=True for full JSON (defaults, min/max).

list_models

class_name, input_name=""

The real model files a loader offers on disk (ground truth), read from its enum — handles both the legacy list and COMBO encodings. Never hallucinate a filename.

search_models

keyword="", model_type=""

The downloadable model catalog (ComfyUI-Manager's list) — find checkpoints/LoRAs/VAEs/upscalers you may not have yet; each result flags whether it's already installed. Install with install_model.

search_templates

keyword="", source="online"

online (default): the full open catalog (Comfy-Org/workflow_templates, ~550), searched by name/title/description live from GitHub — no install. installed: only what's on this ComfyUI.

get_template

name, pack="", source="online", fmt="flowzip"

Fetches a template. fmt="flowzip" (default) is compact FlowZip text (~72% smaller than raw litegraph JSON, median); fmt="json" for full litegraph. Either way it's litegraph — convert with flowzip_to_api before submitting. An online template may need nodes/models you lack — check with find_missing_nodes.

inflate_workflow

flowzip

Expands FlowZip text back into full litegraph JSON.

flowzip_to_api

flowzip

Converts FlowZip/litegraph → API/prompt format for submit_workflow: resolves links, maps widget values to named inputs (type-coerced), and follows Reroute passthroughs back to the real producer — a reroute has no backend class, so a link pointing at one has to be rewired or the API graph references a node that doesn't exist (dangling and cyclic chains are reported, not crashed on). Subgraphs are expanded, not skipped: interiors arrive namespaced <instance>:<inner>, rewired across the boundary, with promoted widget values preserved. Unknown classes are still skipped and reported. Review before running; check_workflow catches the rest before you spend a GPU minute.

template_slots

name, source="online", pack=""

Lists a template's overridable inputs (node_id → params + current values) without loading the full graph — including parameters inside subgraphs. Also returns the author's own Note/MarkdownNote text, where trigger words and required weights actually live, quoted as untrusted data rather than instructions.

run_template

name, overrides={}, source="online", pack=""

Runs a known-good template with {node_id: {input: value}} overrides — fetch → convert → apply → submit — without dumping the graph into context. Then get_result/get_image. Subgraph templates run — their interiors are expanded on the way through.

Extend (install what a template needs — requires ComfyUI-Manager on the host)

Tool

Args

Returns

find_missing_nodes

name, pack="", source="online", workflow=None

Diffs node classes against /object_info and resolves each missing one to the installable pack id. Works on a template or on a workflow you already have (API format or litegraph), recursing into subgraphs. Read-only.

install_node_pack

pack_id, version="latest"

Installs a pack via ComfyUI-Manager's queue (trusted registry, no arbitrary code). Then a restart is required.

install_model

name

Downloads a catalog model (from search_models) into the right models/<type>/ folder via Manager. No restart needed — verify with list_models.

restart_comfyui

Restarts ComfyUI (via Manager) so new nodes register in /object_info. Reports failure honestly: an HTTP response means nothing restarted.

update_comfyui

target="comfyui"|"nodes"|"all"

Updates ComfyUI core and/or every installed pack via Manager's queue, then tells you a restart is required. Runs third-party code — say so first. Not mid-loop: it moves node behaviour under a ratchet whose earlier passes were measured against the old code.

Verify — everything knowable before the GPU is involved

Tool

Args

Returns

check_workflow

workflow (API dict or litegraph)

One answer to "will this run on this box": node classes you don't have (resolved to pack ids in the same pass), model filenames that aren't in that loader's list (with the nearest thing you do have), required inputs left unset, wires pointing at absent nodes, values outside a node's declared range, and a graph with no output node — which runs green and produces nothing to look at. /prompt finds these too: one per submit, with a missing checkpoint looking exactly like a missing pack. Clean here means well-formed, not correct — you still have to look at the pixels.

Build → Run → Look

Tool

Args

Returns

upload_image

path, overwrite=True

Uploads a local image to ComfyUI's input/ dir; returns the name to reference in a LoadImage node.

submit_workflow

workflow (API-format dict), client_id

On success: prompt_id + a "now LOOK" nudge. On failure: node_errors + a "fix that node, re-submit" nudge.

get_result

prompt_id, timeout_s=120

Polls /history; returns each output's filename/subfolder/type, reports how many nodes were served from cache (with fixed seeds only the nodes downstream of your edit re-run — iterations are cheap on purpose), + a directive to look and iterate. A run that died mid-execution comes back as the failing node and its exception (OOM gets a "free_vram, then lower resolution" nudge) instead of the misleading "finished but produced no outputs".

get_image

filename, subfolder="", image_type="output"

The actual image, returned to the model so it can judge the pixels.

compare_images

filename_a, filename_b, mode="side_by_side"|"difference", amplify=1.0

The comparison as an image. difference = 0.5+0.5*(a−b): identical regions read flat mid-gray, so drift you'd never catch by eye pops. An MCP client has no shell for ffmpeg — without this, "diff your outputs" is unexecutable.

image_diff_stats

filename_a, filename_b

Mean/max absolute difference + % of pixels changed — the "I changed only what I meant to" gate. Catches the 'small tweak' that quietly rewrote the frame.

measure_image

filename, metric="sharpness"|"tile_seam"|"brightness"

An objective score for the ratchet, where the brief has an objective test. tile_seam compares the wrap-around join to an interior join (~1.0 = genuinely tiles, >2 = a real seam — the claim an eye waves through); sharpness = edge energy, rises with real detail, falls when a pass just softened the image.

video_info

filename, subfolder=""

Dimensions, fps and frame count for a video output. Call it before indexing frames — you need the range, and you need to know whether two clips you're about to compare are even the same length.

get_video_frame

filename, frame=0, subfolder=""

One frame of a video output by frame index, returned as an image. The video half of get_image: get_result already reports gifs/videos, but every other LOOK tool is Pillow-only and can't decode an mp4 — so for VHS/AnimateDiff/WAN graphs "call get_image and LOOK" was unexecutable.

compare_video_frames

filename_a, filename_b, frame=0, mode="side_by_side"|"difference", amplify=1.0

Same comparison, at the same frame index in both clips. Comparing by timestamp goes quietly wrong the moment lengths differ (a frame cap, a trim, a different fps) — you compare two unrelated moments with full confidence. On a frame-count mismatch the warning is burned onto the image, not left in text you can skim past.

video_temporal_stats

filename, stride=1, max_frames=120, roi=None

Frame-to-frame instability as a number — the objective gate for "does it boil?", which no single still can show. Naive consecutive-frame difference, so real motion counts: use it on the SAME clip before/after a change, or pass an roi over a region that should be static. Validated on a known pair (raw per-frame swap 3.53 → optical-flow smoothed 2.38).

The loop, as durable state — the ratchet is a tool, not a memory exercise. A long loop gets compacted; if best-so-far and the ledger live only in the model's context, the ratchet silently stops ratcheting, the model retries changes it already rejected, and it can hand back a regression as final. So they live on disk.

Tool

Args

Returns

loop_start

brief, gate=""

Opens a run → run_id. gate is the objective test if the brief has one ("must tile seamlessly", "exactly 3 apples").

loop_record

run_id, change, outcome, graph=None, score=None

Records a pass and applies the ratchet. "better" stores that graph as the new best (revertible). "worse"/"same" hands the best graph straight back so reverting is one call — plus the list of changes already tried, so it doesn't repeat a dead end. If both passes carry an objective score, the number overrides the verdict — a model that wants to be finished will call a regression "better".

loop_sweep

run_id, workflow, node_id, input_name, values

Runs the same graph across up to 8 values of one input, in one call — for the values you can't reason your way to (denoise, cfg, strength). Everything else is held identical, so the outputs differ by exactly one variable. The value → prompt_id table is written into the run, so a compacted model recovers it from loop_ledger instead of re-running the sweep. A sweep produces one recorded pass, not N.

loop_best

run_id

The best-so-far graph. The source of truth after a compaction — your recollection isn't.

loop_ledger

run_id

The append-only loop log: every pass, what changed, what it did. Recovers the thread after compaction; it's also the log you hand the user at sign-off.

loop_finish

run_id, summary=""

Closes at the convergence checkpoint; returns the final ledger + best graph to present for sign-off.

loop_report

run_id, out_path=""

Renders the whole run as one self-contained HTML page — every pass, what was kept, what was reverted, thumbnails base64-inlined so it opens with ComfyUI off. The final image proves nothing; the passes you threw away are what show the loop converged.

Deliver

Tool

Args

Returns

save_workflow

workflow (API dict), name="", save=True

API → UI/litegraph so a human can open and edit it, saved into ComfyUI's workflows list. Round-trip verified: the result is converted back to API and diffed against your input, because widgets_values is positional and a silent off-by-one shifts parameters — a plausible-but-wrong file is worse than none.

Control

Tool

Args

Returns

system_stats

Device / VRAM (useful when tuning resolution/batch or after an OOM).

get_queue

What's running and pending.

job_status

prompt_id

Where one run is without blocking: queued (with its position), running, done with N outputs, or the execution error that killed it. What you want with several in flight — a loop_sweep, say.

cancel_job

prompt_id=""

Drops one queued run, or interrupts it if that id is the one executing. No id clears the pending queue and leaves the running job alone. interrupt is the blunt version.

interrupt

Cancels the current run.

free_vram

unload_models=True

Unloads models and resets the executor cache (POST /free). The loop's own cheapness works against you here — cached passes are VRAM — so this is the cheap thing to try before rewriting a graph that OOM'd. Not immediate (lands on the queue worker's next iteration) and can't touch another process's VRAM; confirm with system_stats.

comfyui_logs

lines=60, grep=""

Tails ComfyUI's own log, where failures explain themselves: the traceback inside a node, the OOM, the custom node that failed to import at startup (which is why its class is missing from object_info).

Prompts: comfy_loop (full autonomous method) and comfy_skill (compact skill), both served verbatim from the repo's markdown, plus comfy_install — the bootstrap recipe, generated against the machine the server is running on: an install if one is already there, the interpreter to build the venv from (this server's own, so Python is never a prerequisite to solve), whether comfy-cli and git are present, and the torch build this box's accelerator actually wants (CUDA / ROCm / MPS / none). The server can't run any of it; the agent can, and that is who it's addressed to. Resources: comfyui://object_info (live full dump), comfyui://loop-method, comfyui://skill.


Watch the loop actually work

Driven entirely through this MCP server against a real ComfyUI (RTX 4090, SD1.5), brief: "a crisp, sharply focused macro studio photo of a single red apple on a warm wooden table, fine skin texture, rich detail." Seed fixed at 42 so each pass changes exactly one knob and the effect is attributable. The objective metric is variance-of-Laplacian (a standard sharpness/focus measure).

Five loop passes, left to right: a soft flat apple sharpens into a crisp, saturated, richly textured one

Pass

One change

Sharpness (varLap)

Verdict by looking

1

baseline — 6 steps, cfg 2.5

425

Soft, flat, matte. Weakest.

2

steps 6 → 24

1204

Sharper — but the high number is the wood grain, apple skin still plasticky.

3

cfg 2.5 → 7.5

515

Apple gets richer (saturated, skin speckles) — metric drops because the background softened.

4

euler → dpmpp_2m + karras

740

Winner. Crisp highlight, visible lenticels, believable wood.

5

steps 24 → 36

661

≈ pass 4. Diminishing returns → stop.

The lesson the loop is built on, caught live: the metric peaked at pass 2, but pass 2 is not the best image — its score was inflated by background texture, not apple detail. The winner (pass 4) was chosen by looking. A green number is valid, not correct. (example_apple.png is that pass-4 result.)

…and the other half: when the model is the one that's wrong

The apple shows why you can't trust the metric blindly. This run shows why you can't trust the model blindly — which is the entire reason the ratchet is a tool and not a note in a prompt.

Brief: "a seamlessly tileable cobblestone texture — no visible seam at the wrap," with an objective gate (measure_imagetile_seam). Same seed throughout, so each pass changes exactly one thing. Every texture below is tiled 2×2 — a seam has nowhere to hide.

Three passes tiled 2x2: baseline seams, circular tiling fixes it, x_only brings the seam back and gets reverted

Pass

One change

tile_seam

Ratchet

1

baseline SDXL

h 1.77 · v 1.23 → borderline

kept (first)

2

SeamlessTile + MakeCircularVAE

h 0.78 · v 1.12 → seamless

NEW BEST

3

tilingx_only

h 1.03 · v 1.56 → seam returns

REVERTED

On pass 3 the model told loop_record the result was "better". It wasn't: x_only tiles horizontally and leaves the vertical wrap broken — visible in the right-hand image as stones chopped flat against the horizontal join. The objective score overruled the claim, restored pass 2, and handed the good graph back.

That is the failure this server exists to prevent: an agent that wants to be finished will call a regression an improvement. If best-so-far had lived in the model's context instead of on disk, that regression would have been the final answer.


Install

The short version: ask your agent to do it. Paste this into Claude Code (or any MCP client with a shell) and stop there:

Set up the ComfyUI loop MCP from https://github.com/huikku/comfyui-loop-mcp — register it with my client, and install and launch ComfyUI too if it isn't running.

It has everything it needs to finish that without you: registering the server is one claude mcp add, and once connected, the comfy_install prompt hands back the bootstrap for your machine — an existing ComfyUI to start, the interpreter to build the venv from, the torch build your card actually wants, ComfyUI-Manager, and where to put models. check_comfyui then names anything still missing (no weights, torch on the CPU, no Manager) as things for the agent to fix, not report.

If you'd rather paste config than prose, this runs the server straight from GitHub — nothing to clone, nothing to pip install:

{
  "mcpServers": {
    "comfyui": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/huikku/comfyui-loop-mcp", "comfyui-loop-mcp"],
      "env": { "COMFYUI_URL": "http://localhost:8188" }
    }
  }
}

Claude Code, one line:

claude mcp add comfyui -- uvx --from git+https://github.com/huikku/comfyui-loop-mcp comfyui-loop-mcp

Clone the repo instead and .mcp.json is already there — Claude Code offers the server on first open, no command at all. Reconnect the client after adding it; MCP servers are read at connect time.

Developing on it:

git clone https://github.com/huikku/comfyui-loop-mcp && cd comfyui-loop-mcp
pip install -e .            # or: uv tool install --editable .

Requires Python ≥ 3.10 and a reachable ComfyUI. Installs mcp[cli], httpx, anyio, pillow. Works on both MCP SDK 1.x and 2.x — 2.0 renamed FastMCP to MCPServer and moved the Image helper, which the server imports either way.

Had this installed as comfy-mcp? That name belongs to Comfy-Org's server on PyPI, so this one is now comfyui-loop-mcp (import package comfy_loop, command comfyui-loop-mcp). Run pip uninstall comfy-mcp first, and update your MCP client config. Loop runs already on disk are found automatically — the old ~/.comfy-mcp/runs keeps being used until you point COMFY_LOOP_STATE_DIR somewhere else.

Always-on discipline (Claude Code)

The method also installs as a skill, so it loads on the trigger words instead of waiting to be asked for — ask the agent to do this too, or:

mkdir -p ~/.claude/skills/comfyui-workflows
cp comfy_loop/docs/SKILL.md ~/.claude/skills/comfyui-workflows/

Same file the comfy_skill prompt serves, so the skill and the server can't drift.

Config

Env var

Default

Purpose

COMFYUI_URL

http://localhost:8188

Your ComfyUI server

COMFYUI_ONBOARDING_DIR

repo root above this package

Where the comfy_loop / comfy_skill prompts read their markdown

COMFYUI_TEMPLATES_REF

main

Git ref of Comfy-Org/workflow_templates the online template catalog reads

COMFYUI_TEMPLATES_LIVE

unset

Set to 1 to fetch the freshest catalog index from GitHub instead of the bundled compressed snapshot

COMFY_LOOP_STATE_DIR

~/.comfyui-loop-mcp/runs

Where the ratchet and ledger live. Falls back to a pre-rename ~/.comfy-mcp/runs if that's where your runs already are

Pointing at a remote ComfyUI

ComfyUI usually binds to 127.0.0.1, so a ComfyUI on another machine isn't reachable across the network by default. Two options:

  • SSH tunnel (simplest, keeps ComfyUI private): forward the port, then leave COMFYUI_URL at localhost:

    ssh -N -L 8188:localhost:8188 your-remote-host
    # COMFYUI_URL stays http://localhost:8188
  • Bind ComfyUI to the network and point at it directly (only on a trusted network — this exposes an unauthenticated API):

    python main.py --listen 0.0.0.0 --port 8188
    # COMFYUI_URL=http://<remote-ip>:8188

Use it

  1. In your agent, load the comfy_loop prompt (or let it read the comfyui://loop-method resource) to pull in the full method. If your client injects server instructions, the prefer-looping policy is already active.

  2. Give it a goal. It will check_comfyuilist_nodes / get_node / list_models → build API-format JSON → submit_workflowget_resultget_image, then critique and iterate — one change per pass — until it can't name a defect, then present the result for sign-off.

Troubleshooting

  • "ComfyUI is NOT reachable" — the reply is a set of instructions, not a complaint, and they're addressed to the agent, which has a shell this server doesn't: it looks for a ComfyUI on this machine ($COMFYUI_PATH, comfy-cli's workspace, ~/ComfyUI, ~/comfy, ~/code, ~/github, /opt) and either hands back the start command using that install's own venv python, or the clone + venv + Manager + launch sequence if there is none. If COMFYUI_URL is remote it deliberately does not offer to install locally — that just leaves a second, unused ComfyUI on the wrong box — and gives you the SSH tunnel instead. Every tool returns this, not just check_comfyui; the advice is attached at the transport.

  • Node/model not found — install the pack/model on the ComfyUI side, then restart ComfyUI so /object_info reflects it (the API is stale until then).

  • get_image returns nothing — make sure the graph has a SaveImage / PreviewImage node; get_result lists what was actually produced.

  • install_node_pack blocked / no-op — the install tools need ComfyUI-Manager on the host, and Manager's security level must permit API installs. After installing, restart_comfyui is required before /object_info shows the new nodes.

  • find_missing_nodes picks the "wrong" pack — several packs can export a same-named node; resolution takes the first registry match. If an install doesn't provide the class, check the reported pack and install the right one explicitly.

License

MIT.

Available Tools

32 tools
check_comfyuiA

Confirm ComfyUI is up and reachable (loop step 0).

Returns the installed-node count and device/VRAM. If this fails, ComfyUI isn't running or is on another port — do not start guessing node names.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.5/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Discloses that the tool checks connectivity and returns node count and device/VRAM. It also warns about failure implications. No annotations exist, so the description carries the full burden, but it omits potential side effects or permissions.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two concise sentences that front-load the purpose and immediately provide failure guidance. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given zero parameters and an existing output schema, the description fully covers the tool's behavior, including its role in a loop, return data, and failure implications.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

No parameters exist, so baseline 4 applies. The description adds value by explaining the return values (installed-node count, device/VRAM) beyond the input schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses specific verb 'confirm' and resource 'ComfyUI reachability', clearly stating the tool's purpose as a connectivity check. It distinguishes from sibling tools like 'system_stats' by focusing on reachability and loop integration.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides clear guidance: use for initial connectivity check, and if it fails, do not guess node names. However, it does not explicitly contrast with other tools like 'system_stats' or 'get_node' for when not to use.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

compare_imagesA

See what changed between two passes (loop step 3: LOOK — the comparison).

mode="side_by_side": both outputs on one canvas — what moved, at a glance. mode="difference": 0.5 + 0.5*(a-b) — identical regions read FLAT MID-GRAY and only real changes pop. This is how you answer "did the background actually stay put?", which the eye is bad at. Raise amplify (e.g. 4.0) to surface subtle drift.

Use it every pass against your best-so-far: a change that altered more than you intended is a regression even if the new bit looks nice.

ParametersJSON Schema
NameRequiredDescriptionDefault
modeNoside_by_side
amplifyNo
filename_aYes
filename_bYes
subfolder_aNo
subfolder_bNo

TDQS

A4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, but the description details both modes (side_by_side layout, difference formula with visual result) and the amplify parameter effect. Does not explicitly state it is read-only but implies it.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose, uses bullet-like structure. Somewhat lengthy but each part adds value; could tighten file parameter explanation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no annotations, no output schema, and 6 parameters, the description covers key behavioral details (mode, amplify, use case) but omits file parameter semantics and return value information, leaving gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, so description must compensate. Explains mode and amplify well (2 of 6 parameters), but leaves filename_a, filename_b, subfolder_a, subfolder_b undocumented. Partial coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool compares two images ('See what changed between two passes') and ties it to a loop step, distinguishing it from siblings like image_diff_stats (numerical stats) and get_image (retrieve).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides practical guidance: use every pass against your best-so-far, and explains when to use each mode. Lacks explicit when-not-to-use or alternative tools, but context is strong.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

find_missing_nodesA

Diff a template's nodes against what's installed, and resolve each missing node to the pack that provides it (via ComfyUI-Manager's registry mapping).

Fetches the template (same args as get_template), lists the node classes it uses, subtracts what /object_info already has, and for each missing class reports the installable pack id to pass to install_node_pack. Read-only.

ParametersJSON Schema
NameRequiredDescriptionDefault
nameNo
packNo
sourceNoonline

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.3/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description fully carries the behavioral disclosure burden. It explicitly declares the tool is 'Read-only' and details the steps: fetches template, lists node classes, subtracts what's installed, and reports missing nodes with pack IDs. This provides full transparency about inputs, process, and outputs without contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise, with two clear paragraphs: the first states the core purpose, and the second elaborates the process. Every sentence adds value without fluff. It is front-loaded with the main action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that the tool has an output schema (not shown but indicated), the description does not need to detail return values. It covers the tool's purpose, process, and relation to siblings. It explains dependencies (template, object_info, registry mapping). The only gap is parameter documentation, which is evaluated separately. Overall, it provides sufficient context for effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 0% description coverage. The description only mentions 'same args as get_template', which adds minimal context by referencing another tool but does not explain the meaning or usage of the individual parameters (name, pack, source). This is insufficient for an agent to understand parameter semantics without external knowledge.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's function: 'Diff a template's nodes against what's installed, and resolve each missing node to the pack that provides it'. It specifies the action (diff and resolve) and resource (template nodes vs installed). This distinguishes it from siblings like get_template (fetches template) and install_node_pack (installs packs).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description states it uses the same args as get_template, implying it should be used after fetching a template and before installing missing nodes with install_node_pack. It notes the process of subtracting installed nodes, guiding usage context. However, it does not explicitly state when not to use it or mention alternatives beyond referencing siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

flowzip_to_apiA

Convert FlowZip (or litegraph) into API/prompt format ready for submit_workflow.

Inflates FlowZip if needed, then maps the litegraph to the flat API graph using the live object_info (resolves links, maps widget values to named inputs). This is the bridge for authoring/adapting graphs compactly and running them.

Best-effort: subgraph instances and unknown nodes are skipped and reported; widget drift between an old template and a newer node shows up as a node_errors when you submit_workflow the result — read it, fix that node, re-submit. Review the API graph before running.

ParametersJSON Schema
NameRequiredDescriptionDefault
flowzipYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.2/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries full responsibility. It details the transformation process (inflating, mapping, resolving links) and discloses limitations (best-effort, skipped subgraphs, widget drift leading to errors). However, it does not explicitly state whether the operation is read-only or has side effects.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise, front-loaded with the main purpose, and each sentence adds value without redundancy. It efficiently conveys the tool's function, best-effort nature, and post-processing advice.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that an output schema exists, the description need not explain return values. It covers the conversion process, edge cases (skipped nodes, widget drift), and provides guidance. It is reasonably complete for a converter tool, though it could mention prerequisites like live object_info.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has 0% coverage for the single parameter 'flowzip', so the description must compensate. It explains that the parameter is a FlowZip or litegraph and can be inflated, which adds meaning beyond the empty schema. However, it lacks details on format, encoding, or constraints.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description starts with a clear verb 'Convert' and specifies the resource 'FlowZip (or litegraph)' with a target format 'API/prompt format ready for submit_workflow'. It distinguishes itself from siblings like inflate_workflow and submit_workflow by describing its bridging role.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description states that this tool is intended for authoring/adapting graphs compactly and as a step before submitting workflows. It provides guidance on handling errors ('review the API graph before running') but does not explicitly compare to alternatives or specify when not to use it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_imageB

Fetch a rendered output so you can LOOK at it (loop step 3: LOOK — part 2).

Returns the actual image to the model. This is the step that makes the loop work: don't declare a workflow done off a green run — view the pixels, judge them against the brief, then change one thing and re-run.

ParametersJSON Schema
NameRequiredDescriptionDefault
filenameYes
subfolderNo
image_typeNooutput

TDQS

B3.1/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description discloses that the tool returns the actual image to the model, implying a read-only retrieval. Since no annotations are provided, the description carries the full burden for behavioral disclosure. While adequate for the core behavior, it omits potential side effects (e.g., does it consume the image? is there caching?) and does not address authentication or rate limits.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two paragraphs with some repetition (e.g., 'loop step 3: LOOK — part 2' revisited). It could be more concise by merging the first sentence and the loop context. Overall, it is somewhat verbose for the information conveyed.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given three parameters with no schema descriptions and no output schema, the description leaves significant gaps: it does not explain which parameter is required (filename), what format identifiers take, or what the response contains. For a tool that returns binary image data, the absence of error handling or type hints is a deficiency.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description provides zero information about the three parameters (filename, subfolder, image_type). With 0% schema description coverage, the description must compensate but fails entirely. The agent receives no guidance on how to specify which image to fetch, making correct invocation difficult.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool fetches a rendered output image for visual inspection, using active verbs like 'Fetch' and 'LOOK'. It distinguishes itself from siblings by embedding the tool in a loop workflow (step 3: LOOK), though it does not explicitly compare with similar tools like 'compare_images'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit usage context: this is part of a loop where the agent should view pixels and judge against the brief before re-running. It advises against declaring workflow done based on a green run alone. However, it lacks explicit when-not-to-use or mention of alternatives like 'compare_images' for comparison tasks.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_nodeD
ParametersJSON Schema
NameRequiredDescriptionDefault
verboseNo
class_nameYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

D1/5.0
Behavior1/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Tool has no description.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness1/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Tool has no description.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness1/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Tool has no description.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Tool has no description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose1/5

Does the description clearly state what the tool does and how it differs from similar tools?

Tool has no description.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines1/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Tool has no description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_queueA

Show what's running and pending in ComfyUI's execution queue.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.1/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Note is a read operation, no params, output schema exists. Description does not explicitly confirm read-only nature or mention side effects, but tone suggests no destructive actions. Adequate given simplicity.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence with clear subject and action. No extraneous information. Front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given zero parameters and presence of output schema, description is complete enough. No additional details needed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

No parameters exist; schema coverage is 100%. Description adds nothing beyond schema, but baseline for 0 parameters is 4.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states the tool shows running and pending items in ComfyUI's execution queue. Verb 'show' and resource 'execution queue' are specific. Distinguishes from siblings like 'submit_workflow' and 'interrupt'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Description implies use when checking queue status but does not explicitly state when to use or compare with alternatives like 'system_stats' or 'check_comfyui'. No exclusion criteria.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_resultA

Poll /history for a submitted prompt and return its output files (loop step 3: LOOK — part 1, find what was produced).

Blocks up to timeout_s for the run to finish. Returns each output's filename / subfolder / type — feed those to get_image to view the pixels.

ParametersJSON Schema
NameRequiredDescriptionDefault
prompt_idYes
timeout_sNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.1/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. It discloses blocking behavior up to timeout_s and polling, but does not mention error handling, rate limits, idempotency, or whether it's read-only. Basic behavioral info is present.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with a clarifying note. It is efficient and front-loaded with the core action, though the loop reference adds some extraneous context for a multi-step process.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a polling tool with two parameters and an output schema, the description covers the core behavior (blocking, output format, follow-up with get_image). It lacks details on error cases or timeout handling, but the output schema likely documents return values.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema has 0% description coverage, so description must compensate. It explains timeout_s as the blocking duration, and the prompt_id is implicitly the identifier for the submitted prompt. This adds meaning beyond the schema's titles.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool polls /history for a submitted prompt and returns output files, specifying the action (poll), resource (history for a prompt), and result (output files). It distinguishes from siblings like get_image (which views pixels) and get_node (which gets node info).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description says to use after submitting a prompt, blocks up to timeout_s, and directs to feed outputs to get_image. It implies when to use but does not explicitly state when not to use or mention alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

get_templateA

Fetch one workflow template as a known-good starting point.

source="online" (default): from the official GitHub catalog — no install needed; pack is ignored. source="installed": from this ComfyUI (pack required).

fmt="flowzip" (default): compact FlowZip text — ~72% fewer tokens than the raw litegraph JSON (median), enough to read/adapt the graph. fmt="json": the full litegraph. Either way it's litegraph, NOT the API/prompt format submit_workflow needs — adapt to API (resolve passthroughs, widgets_values -> named inputs via get_node), or inflate a FlowZip with inflate_workflow. If from the online catalog, first confirm you have its nodes/models — run find_missing_nodes then install_node_pack, or verify with list_nodes/list_models.

ParametersJSON Schema
NameRequiredDescriptionDefault
fmtNoflowzip
nameYes
packNo
sourceNoonline

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A5/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations present, so description fully carries the burden. Discloses that output is litegraph format (not API), token reduction stats, and that online templates require node/model verification.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Well-structured with front-loaded purpose, then clear bullet-like explanation of parameters and usage context. Every sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (4 parameters, output schema exists, sibling tools like search_templates and run_template), the description is complete. It explains the output format, prerequisites, and next steps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, but description explains all four parameters in detail: name, source (behavior of online vs installed), pack (required for installed), and fmt (flowzip vs json, with token savings). Adds significant meaning beyond schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states the verb 'Fetch', resource 'workflow template', and distinguishes between online and installed sources. Does not explicitly differentiate from sibling 'search_templates' but provides enough context to avoid confusion.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit guidance on when to use online vs installed, flowzip vs json, and mentions post-fetch steps like adapting to API format or checking nodes/models via other tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

image_diff_statsA

Quantify the change between two passes — the 'I changed only what I meant to' gate.

Returns mean/max absolute difference and the % of pixels that moved. Pair it with compare_images: the picture tells you WHAT changed, this tells you HOW MUCH — and catches the case where a 'small tweak' quietly rewrote the frame.

ParametersJSON Schema
NameRequiredDescriptionDefault
filename_aYes
filename_bYes
subfolder_aNo
subfolder_bNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A3.6/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses the return values (statistical metrics) and implies a read-only operation, but does not explicitly state that the tool does not modify files or require special permissions. The warning about catching unintended changes adds some transparency, but more explicit statements about safety and side effects would improve it.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with a line break, each sentence adds value. It is front-loaded with the core purpose and includes a memorable phrase ('I changed only what I meant to' gate) that helps recall. No extraneous information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description covers the main return values and the relationship with a sibling tool. However, it fails to address how the optional subfolder parameters affect behavior or defaults. Since an output schema exists (not shown), the return structure can be assumed documented, but parameter usage context is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, meaning the input schema lacks descriptions for all 4 parameters. The description does not mention any parameter names, purposes, or usage details (e.g., what filename_a and filename_b refer to, or how subfolders work). For a tool with 4 parameters and no schema descriptions, the description must compensate, but it provides zero parameter guidance.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states that the tool quantifies change between two image passes, returning mean/max absolute difference and percentage of pixels changed. It differentiates from the sibling CompareImages by explaining that CompareImages shows what changed while this tool shows how much, and it warns about detecting unintended large changes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly recommends pairing with compare_images and explains the complementary roles (what vs. how much). It does not provide explicit when-not-to-use scenarios, but the context is sufficiently clear for an AI agent to decide when to invoke this tool over alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

inflate_workflowA

Expand FlowZip text back into a full litegraph workflow JSON.

Reverse of the FlowZip that get_template returns. Structure (nodes, types, links, widget values) is preserved; cosmetic fields are not. To RUN it, still adapt the litegraph to API/prompt format for submit_workflow.

ParametersJSON Schema
NameRequiredDescriptionDefault
flowzipYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. It discloses that structure (nodes, types, links, widget values) is preserved while cosmetic fields are not, clearly detailing behavioral traits beyond schema. Minor omission: no mention of error handling or side effects.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three concise sentences: first describes action, second specifies preservation, third gives post-processing steps. No wasted words, front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given one parameter and an existing output schema, the description covers input, behavior, and next steps adequately. Could mention potential errors from invalid flowzip, but overall complete for the tool's complexity.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema description coverage, the description compensates by explaining that 'flowzip' is FlowZip text from get_template. It adds meaning about the parameter's origin and format beyond the schema type string.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states 'Expand FlowZip text back into a full litegraph workflow JSON' and distinguishes from siblings like get_template (which produces FlowZip) and flowzip_to_api (which converts to API format). Verb 'expand' and resource 'FlowZip to litegraph JSON' are specific.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly indicates it is the reverse of get_template and that the output must be adapted for submit_workflow, providing context on when to use. Could be more explicit about alternatives, but effectively guides the agent.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

install_modelA

Download a model from the catalog by its exact name (from search_models), into the correct models// folder, via ComfyUI-Manager.

Trusted catalog only — Manager whitelists the source. Unlike nodes, models do NOT need a ComfyUI restart (loaders re-scan the folder); once it completes, verify with list_models. Large models can take a while — the download continues server-side even if this call's poll window ends.

ParametersJSON Schema
NameRequiredDescriptionDefault
nameYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, yet description covers key behaviors: no restart needed, async continuation, and trust/whitelist source. Lacks specifics on error handling or permissions, but provides substantial transparency for a tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, no redundancy, front-loaded with the main action. Every sentence adds value: the how, the constraints, and important behavioral notes.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given existence of output schema (not shown), return values need not be explained. The description covers parameter source, folder destination, async behavior, and verification step. Could mention failure modes, but overall adequate for context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only one parameter 'name' with 0% schema description coverage. The description adds crucial semantic context: the name must be an exact catalog name from search_models. This compensates well for the bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action (download/install), the resource (model from catalog), and the destination (models/<type>/ folder). It distinguishes from nodes (no restart needed) and references sibling tool search_models for exact name, making intent and scope unmistakable.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly tells to use exact name from search_models and to verify with list_models after completion. Also warns about large model download times and server-side continuation. Does not explicitly say when not to use, but the context is clear enough.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

install_node_packA

Install a custom-node pack by its ComfyUI-Manager registry id (from find_missing_nodes) — trusted registry only, no arbitrary code.

Queues the install, starts the queue, and polls until done. A ComfyUI RESTART is required afterward before /object_info reflects the new nodes — call restart_comfyui, then re-query. Fails clearly if Manager's security level blocks API installs.

ParametersJSON Schema
NameRequiredDescriptionDefault
pack_idYes
versionNolatest

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.3/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description fully discloses the behavior: queues, starts, polls, requires restart, and fails on security blocks. Mentions trust and safety, providing clear expectations for the agent.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two concise sentences plus a brief note; every sentence adds value. Front-loaded with core action and key constraint, then details the process and post-condition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers the full workflow: queueing, polling, restart requirement, and error handling. Output schema exists, so return value explanation is unnecessary. Complete for an agent to use correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Explains pack_id as the registry id from find_missing_nodes, but does not clarify the version parameter (its default 'latest' is only in schema). Schema coverage is 0%, so description partially compensates but leaves a gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states the tool installs a custom-node pack using its ComfyUI-Manager registry id, specifying the source as 'trusted registry' and referencing find_missing_nodes for the id. Distinguishes from sibling tools like install_model and find_missing_nodes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Indicates the tool should be used for trusted registry packs, mentions the prerequisite of obtaining the id from find_missing_nodes, and advises a subsequent restart via restart_comfyui. Does not explicitly state when not to use, but the context implies avoidance for arbitrary code.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

interruptA

Cancel the currently executing prompt.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4/5.0
Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided; the description lacks any behavioral details beyond the action itself, such as side effects, reversibility, or state requirements.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, concise sentence that front-loads the essential information with no unnecessary words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has no parameters and a straightforward purpose, the description is mostly complete. However, it could mention expected state or result beyond the action.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

No parameters exist (schema coverage 100%), so the description does not need to add parameter information. Baseline score of 4 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool cancels the currently executing prompt, specifying the action and target. It distinguishes from sibling tools like 'submit_workflow' or 'loop_start'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies using the tool to stop execution, but does not explicitly state when not to use it or provide alternatives. Context from siblings suggests a clear use case.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

list_modelsA

List the real model files a loader offers (loop step: never hallucinate a checkpoint/LoRA/VAE filename).

Reads the loader's enum from object_info (handles both the legacy list and the newer COMBO encoding). If input_name is omitted, reports every enum-typed input on the node. Pick ONLY from the returned list.

ParametersJSON Schema
NameRequiredDescriptionDefault
class_nameYes
input_nameNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.2/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Despite no annotations, the description discloses how the tool works: it reads the loader's enum from object_info, handles both legacy list and COMBO encoding, and reports every enum-typed input if input_name is omitted. This provides good transparency, though it could mention the output format (which is covered by output schema).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is succinct yet informative: a single sentence for purpose, then technical details, then usage warning. Every sentence adds value without repetition. It is well-structured and easy to read.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity, the description provides sufficient context: purpose, technical behavior, parameter guidance, and a caution. An output schema exists to cover return values. It could include an example or mention of expected response, but overall it is complete enough for an agent to use correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 0% description coverage, so the description must compensate. It explains the effect of omitting input_name (reports all enum-typed inputs) and implies that class_name identifies the loader. However, it does not fully describe class_name, and the description is incomplete for the class_name parameter.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'List the real model files a loader offers'. It specifies the resource (model files) and action (list), and adds context about avoiding hallucination. This differentiates it from sibling tools like search_models (which searches) and install_model (which installs).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives explicit guidance: 'never hallucinate a checkpoint/LoRA/VAE filename' and 'Pick ONLY from the returned list'. It explains when input_name can be omitted to get all enum-typed inputs. However, it does not explicitly mention when not to use this tool or suggest alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

list_nodesA

Search installed nodes by keyword (loop step: discover, don't guess).

Matches the keyword against BOTH the class name and the display name, so a node found by its UI label ("Load Image") still turns up. Returns class_name -> display_name. Class names are case-sensitive and differ from display names — use the class_name in workflow JSON. Omit keyword to get the total count only (the full list is large).

ParametersJSON Schema
NameRequiredDescriptionDefault
keywordNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.8/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Given no annotations, the description fully discloses behavior: dual matching, case sensitivity, display name vs class name distinction, count-only mode when keyword omitted.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Concise, front-loaded with main purpose, every sentence adds value. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given one optional parameter and an output schema, the description covers input behavior, return format, and edge cases (omitting keyword). Complete for the tool's complexity.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema coverage, the description explains the 'keyword' parameter meaning and behavior (optional, default empty, count mode). Adds significant value beyond schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states 'Search installed nodes by keyword' and distinguishes from siblings like 'get_node' and 'find_missing_nodes'. Specifies matching against class and display names, and returns a mapping.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides context for usage: keyword search, and omitting keyword for count. Does not explicitly list when not to use, but sibling differentiation is implied by description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_bestA

Fetch the best-so-far graph — to revert to it, or to deliver it as the final.

Use this after a compaction, or any time you're unsure the graph in your context is still the best one. It is the source of truth; your memory is not.

ParametersJSON Schema
NameRequiredDescriptionDefault
run_idYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A3.6/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Describes the tool as the 'source of truth' implying authority and reliability, but does not disclose side effects or read-only nature given no annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences with no waste: purpose, when to use, and a behavioral trait. Excellent front-loading.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the existence of an output schema, the description adequately covers purpose and usage, though it could mention the return value type.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, and the description adds no meaning to the `run_id` parameter beyond the schema's title 'Run Id'.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it fetches the best-so-far graph for reverting or delivery. However, it does not differentiate from sibling loop tools like loop_finish or loop_start.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly recommends use after compaction or when unsure about the current graph's validity. Lacks a direct 'when not to use' statement.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_finishA

Close the loop at the convergence checkpoint — you can't name a defect anymore.

Marks the run converged and returns the final ledger + the best graph, ready to present. Then STOP and ask the user to approve or request changes; don't keep inventing variations to avoid stopping.

ParametersJSON Schema
NameRequiredDescriptionDefault
run_idYes
summaryNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.3/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description fully discloses behavior: it closes the loop, marks convergence, returns final ledger and best graph, and instructs the agent to stop. No contradictory or missing behavioral aspects are present.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences, front-loads the main action, and contains no extraneous words. Every sentence is meaningful and earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the presence of an output schema, the description need not explain return values. It covers purpose, guidelines, and behavior well. However, the lack of parameter documentation is a gap, slightly reducing completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the description does not mention the parameters 'run_id' or 'summary'. It fails to add meaning beyond the input schema, which is critical given the low coverage. The agent must guess the purpose of these parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'close the loop' and the resource 'convergence checkpoint', and explains that it marks the run as converged and returns the final ledger and best graph. This distinguishes it from sibling tools like loop_start and loop_record, which are for earlier stages.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicit usage guidance is provided: after convergence, stop and ask for user approval. It warns against continuing to invent variations, which is a clear when-not-to-use instruction.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_ledgerA

The append-only loop log: every pass, what changed, what it did.

Read it after a context compaction to recover the thread — what the brief was, what's already been tried (so you don't retry a dead end), and which pass is best. This is also the log you hand the user at sign-off; it's the story of how the result got good.

ParametersJSON Schema
NameRequiredDescriptionDefault
run_idYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A3.9/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It describes the tool as read-only ('append-only', 'read it') and discloses the content: what changed, what it did. It also explains behavioral context (recover thread, avoid retries, best pass). This provides sufficient transparency for an agent.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise (three sentences) and front-loaded with the core purpose. Each sentence adds value: stating it is append-only, describing its contents, and listing use cases. There is no wasted text, though the parameter is entirely unaddressed.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (one required parameter) and the presence of an output schema (documenting return values), the description adequately covers purpose and usage context. However, the lack of parameter explanation is a notable gap. The description would be complete if it briefly mentioned that run_id identifies the loop session.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The only parameter, run_id, has no schema description (0% coverage) and the tool description does not explain what run_id represents or how to obtain it. The description focuses on the tool's output and usage context, not the input parameter. This leaves the agent without guidance on what value to provide.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool is an append-only loop log that records each pass, what changed, and what it did. It specifies the purpose: read after context compaction to recover thread, avoid retrying dead ends, determine best pass, and provide user sign-off. This distinguishes it from sibling tools like loop_record (which likely records) and loop_report (which likely summarizes).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly states when to use the tool: 'Read it after a context compaction to recover the thread' and 'hand to user at sign-off'. It implies it is for reading only, but does not explicitly mention when not to use it or alternatives. The purpose is clear enough that usage context is well-understood.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_recordA

Record a pass and apply the ratchet (loop step 5: DECIDE).

change the ONE thing you changed this pass ("denoise 0.6 -> 0.45"). outcome your verdict vs the best-so-far: "better" | "worse" | "same". graph the API graph you just ran — REQUIRED when outcome is "better", because that's what gets stored as the new best and handed back on a revert. score an objective score from measure_image, when the brief has a gate. If both this pass and the best have one, the NUMBER decides — not your verdict. (A model that wants to be finished will call a regression "better".) outputs this pass's output files, straight from get_result — pass them through so loop_report can show what each pass actually looked like.

On "worse"/"same" you get the best graph back: revert to it and try a DIFFERENT change. Never build on a regression — that's how a loop wanders instead of converging.

ParametersJSON Schema
NameRequiredDescriptionDefault
noteNo
graphNo
scoreNo
changeYes
run_idYes
outcomeYes
outputsNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.6/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description must disclose behavioral traits. It explains the revert behavior on 'worse'/'same,' the requirement for graph with 'better,' and the role of score. It also mentions passing outputs for loop_report. However, it does not explicitly describe side effects or error handling, but the key behaviors are covered.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is somewhat lengthy but well-structured, with bullet points for parameters and clear explanations. It front-loads the purpose. Minor redundancy (e.g., 'Never build on a regression' is reiterated) could be trimmed, but overall it is efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of the tool (7 parameters, loop context) and the presence of an output schema, the description covers the essential aspects: input parameter behavior, decision logic, and the revert mechanism. It does not detail return format, but the output schema likely handles that. The description is sufficient for an agent to use the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must add meaning for each parameter. It explains 'change' as the modification made, 'outcome' as verdict vs best-so-far, 'graph' as required when outcome is 'better,' 'score' as an objective measure for gates, 'outputs' as files for loop_report, and 'note' and 'run_id' implicitly. This provides significant value beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Record a pass and apply the ratchet (loop step 5: DECIDE).' It specifies the verb 'Record a pass and apply the ratchet' and the resource 'loop step 5.' The purpose is distinct from sibling tools like loop_start, loop_best, loop_finish, etc.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit guidance on when and how to use the tool. It explains that on 'worse' or 'same' outcomes, the best graph is returned and a different change should be tried. It also notes that graph is required when outcome is 'better,' and explains the role of score in decision-making. This distinguishes usage from alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_reportA

Render the whole run as ONE self-contained HTML page — every pass, what changed, what was kept, what was reverted, and the final.

This is the artifact worth keeping. The final image alone proves nothing; the evidence of convergence — the passes you threw away — is what shows the loop actually worked. Hand it over at the sign-off checkpoint alongside the result.

Images are downscaled and base64-inlined, so the page renders with ComfyUI off, on someone else's machine, or emailed. Writes next to the run state by default; set out_path to put it anywhere.

ParametersJSON Schema
NameRequiredDescriptionDefault
run_idYes
out_pathNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.2/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description solely discloses key behaviors: images are downscaled and base64-inlined, the page can render offline or via email, and output is written next to the run state by default with optional out_path. This covers important traits beyond the schema, though permissions or performance are not addressed.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise and well-structured: it starts with the primary purpose, explains why this artifact is important, then provides technical details about image handling and output location. Every sentence adds value without being verbose.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that an output schema exists (though not shown), the description need not explain return values. It covers the tool's purpose, usage, output format, and file location. However, it does not indicate whether the result is a success message or status, which might be useful.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has 0% description coverage, but the description explains that out_path can be set to place the report anywhere, adding meaning beyond the schema's default string type. The run_id parameter is implied by context (the run to report), but no explicit description is given. This is adequate but not rich.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool renders the entire run as a self-contained HTML page, detailing what changed, was kept, reverted, and final. This is specific to generating a final report, distinguishing it from siblings like loop_best or loop_record which handle other aspects of the loop workflow.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for when to use the tool: at the sign-off checkpoint alongside the result, emphasizing the artifact's value as evidence of convergence. However, it does not explicitly state when not to use it or reference alternative tools, though the purpose is sufficiently distinct.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

loop_startA

Open a loop run — do this BEFORE the first submit (loop step 0).

brief is what "right" means, in the user's words; you'll be judged against it. gate is the objective test IF the brief has one ("must tile seamlessly", "exactly 3 apples", "identity preserved") — leave empty for purely aesthetic work.

Returns a run_id. Pass it to loop_record every pass. This is what makes the ratchet real: your best graph is stored HERE, not in your context, so it survives compaction and can actually be reverted to.

ParametersJSON Schema
NameRequiredDescriptionDefault
gateNo
briefYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, but description covers key behavioral traits: returns run_id, stores best graph externally for persistence across compaction, enables reversion. Does not mention authorization or rate limits, but adequate for a start tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three paragraphs with clear structure: imperative instruction, parameter explanations, return value and significance. Concise but could be slightly tighter; no wasted sentences.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Fully covers purpose, usage timing, parameter semantics, return value (run_id), and behavioral significance. Output schema exists but description adds value beyond it. Complete for a start tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema has 2 params with 0% description coverage, but description adds substantive meaning: 'brief is what right means' and 'gate is the objective test'. Compensates for lack of schema-level descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states it opens a loop run, with specific verb+resource ('Open a loop run'). Distinguishes from sibling tools like loop_record, loop_best, etc. by explaining this is step 0.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicit timing instruction: 'do this BEFORE the first submit'. Explains when to use 'gate' (if brief has objective test) vs leave empty. Does not explicitly mention when not to use, but context of siblings provides differentiation.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

measure_imageA

Score an output objectively, for the ratchet (metric: sharpness | tile_seam | brightness).

Use ONLY where the brief has an objective test — then feed the score to loop_record so the ratchet can't be fooled by a model that wants to be done:

tile_seam "seamless texture" — compares the wrap-around join to an interior join. ~1.0 = genuinely tiles; >2 = a real seam. The eye waves this through. sharpness "upscale/restore, add detail" — edge energy. Rises with real detail, falls when a pass just softened the image. Compare ACROSS passes. brightness mean / stddev / p99 — exposure and blown-highlight checks.

A score is not the judgement. A graph with a great number can still look wrong — gate on the metric, decide with your eyes.

ParametersJSON Schema
NameRequiredDescriptionDefault
metricNosharpness
filenameYes
subfolderNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.2/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description explains what each metric measures (e.g., tile_seam compares wrap-around join to interior join). However, it does not explicitly state if the tool is read-only or if it requires specific permissions, though this is implied by its measurement nature.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is relatively concise but uses line breaks and dashes that may not render well in all contexts. It is front-loaded with the main purpose, and each sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the existence of an output schema (not described) and no annotations, the description covers the main use case well. However, it does not mention the return type or output schema, and lacks explanation of 'objective test'.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema description coverage, the description only adds context for the metric parameter by listing values and meanings. It does not explain the filename or subfolder parameters, leaving them solely to the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Score an output objectively' for specific metrics (sharpness, tile_seam, brightness). It distinguishes itself from siblings by focusing on objective measurement for the ratchet system.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly states when to use: 'Use ONLY where the brief has an objective test' and advises feeding scores to loop_record. Also warns that 'A score is not the judgement' and to use eyes, providing clear context and exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

restart_comfyuiA

Restart ComfyUI (via ComfyUI-Manager) so newly installed nodes register in /object_info. The server is briefly unavailable; poll check_comfyui after.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. Discloses that server is briefly unavailable and recommends polling check_comfyui. Adequately transparent for a restart operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with purpose and context, no wasted words. Efficient and clear.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given no parameters and existing output schema, description covers why, side effect, and follow-up. Could mention output schema content but not required.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Input schema has zero parameters, baseline is 4. No additional parameter info needed, description handles purpose and behavior.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states 'Restart ComfyUI', a specific verb+resource, and explains the purpose: to register newly installed nodes in /object_info. Differentiates from siblings like check_comfyui and install_node_pack.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Implies usage after installing nodes to register them, and explicitly tells agent to poll check_comfyui after restart. No explicit when-not-to-use, but context is clear.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

run_templateA

Run a known-good template with input overrides — WITHOUT loading the graph into context. Fetches the template, converts to API format, applies overrides, and submits. Use template_slots first to see what you can override.

overrides: {node_id: {input_name: value}} (node ids and inputs from template_slots). After it runs, call get_result then get_image and LOOK — a green run is valid, not correct.

Limitation: subgraph templates can't be expanded (converter coverage ~88% of non-subgraph nodes); if nodes are skipped it's reported and the run may be incomplete. Confirm the template's nodes/models exist first (find_missing_nodes).

ParametersJSON Schema
NameRequiredDescriptionDefault
nameYes
packNo
sourceNoonline
client_idNocomfy-mcp
overridesNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.3/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so the description carries full burden. It details the internal steps (fetch, convert, apply overrides, submit), discloses the converter coverage (~88%) and that skipped nodes are reported. It does not explicitly state whether the operation is read-only or modifies state, but the context implies it executes a run (non-destructive). Overall, good behavioral disclosure beyond the missing annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is relatively concise and well-structured: purpose, usage, overrides format, post-run steps, and limitations. Minor informal phrasing ('LOOK') but adds clarity. Could be slightly tighter, but effectively communicates essential information without verbosity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the presence of an output schema (context signal), the description does not need to detail return values. It provides sufficient context: prerequisites (template_slots, find_missing_nodes), the process, limitations (subgraph, converter coverage), and post-run actions. Lacks explanation of 'pack' and 'source' but defaults are provided. Reasonably complete for a complex tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. It explains the 'overrides' parameter in detail (format: {node_id: {input_name: value}} and source from template_slots). However, it does not explain 'pack', 'source', or 'client_id' beyond default values. While overrides is the most complex parameter, the lack of explanation for others reduces the score.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly specifies the action ('Run a known-good template with input overrides') and resource ('template'), distinguishing it from siblings like 'submit_workflow' and 'get_template'. It emphasizes the key differentiator: 'WITHOUT loading the graph into context.'

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly instructs to use 'template_slots' first for overrides, and after execution to call 'get_result' then 'get_image' (with a caveat about interpreting results). Also recommends confirming node/model existence with 'find_missing_nodes', and notes the limitation with subgraph templates. Provides clear when-to-use and when-not-to-use guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

save_workflowA

Convert an API graph to UI/litegraph format so a human can open and edit it.

The loop builds API format because that's what /prompt runs — it is NOT the file you drag onto the ComfyUI canvas. Call this when the user asks for the editable workflow.

The result is VERIFIED by converting it back to API format and diffing against what you passed in; any mismatch is reported. widgets_values is positional and a silent off-by-one shifts parameters — a plausible-but-wrong file is worse than none, so if the round-trip doesn't match, fix it before shipping it.

With save=True and a name, it's written to ComfyUI's workflows dir so it shows up in the UI's workflow list.

ParametersJSON Schema
NameRequiredDescriptionDefault
nameNo
saveNo
workflowYes

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.9/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. It discloses verification via round-trip diffing, warns about silent off-by-one in widgets_values, and explains that mismatches are reported and should be fixed. Also describes save behavior comprehensively.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise (about 90 words) yet thorough. Each sentence adds value, front-loading the primary purpose and then covering verification, warnings, and save behavior without redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity and the presence of an output schema, the description covers all necessary behavioral details: purpose, when to call, verification mechanism, edge case warnings, and persistence. No gaps remain.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, but the description adds meaning: workflow is the API graph, name and save control persisting the file. It explains the role of each parameter beyond the schema, compensating for the lack of schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Convert an API graph to UI/litegraph format so a human can open and edit it.' It specifies the verb 'convert' and resource, and distinguishes from sibling tools by noting that the loop builds API format and this tool is for the editable format.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says 'Call this when the user asks for the editable workflow.' It also implies when not to use it (the loop builds API format) and explains the save behavior. Additionally, it provides guidance on handling widgets_values positional off-by-one errors.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

search_modelsA

Search the downloadable model catalog — find checkpoints/LoRAs/VAEs/ controlnets/upscalers you may NOT have installed yet (the local equivalent of the cloud's model search). Reads ComfyUI-Manager's model list; each result shows whether it's already installed on THIS box.

Filter by keyword (name/filename/base/description) and optional model_type (checkpoint, lora, vae, controlnet, upscale, clip, diffusion_model, ...). Install one with install_model(name). Requires ComfyUI-Manager on the host.

This is a catalog of known models; list_models shows what a specific loader currently offers on disk (ground truth). Discover here, then verify against list_models after installing.

ParametersJSON Schema
NameRequiredDescriptionDefault
keywordNo
model_typeNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.5/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Discloses it reads ComfyUI-Manager's model list, shows installation status, and requires the add-on; no obvious undisclosed behaviors.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded purpose, efficient but slightly lengthy; every sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers purpose, usage, parameters, prerequisites, and sibling relationship; output schema exists but not described, acceptable.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema coverage, description explains keyword filters (name/filename/base/description) and model_type with examples, compensating well.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states it searches a downloadable model catalog for models not yet installed, lists specific model types (checkpoints, LoRAs, etc.), and distinguishes from list_models.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly when to use (discover models) vs list_models (verify installation), and states prerequisite (ComfyUI-Manager).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

search_templatesA

Search known-good workflow templates to adapt (few-shot beats zero-shot).

source="online" (default): the OFFICIAL open catalog on GitHub (Comfy-Org/workflow_templates) — the same ~550-template set the Cloud MCP's search is built from. You do NOT need these installed; they're browsed straight from the repo. Matches keyword against name + title + description.

source="installed": only templates on THIS ComfyUI right now (/api/workflow_templates — every installed pack's example workflows). Smaller, but guaranteed runnable on your install without adding anything.

Then fetch one with get_template. Note an online template may reference nodes/ models you haven't installed — reconcile against object_info before running.

ParametersJSON Schema
NameRequiredDescriptionDefault
sourceNoonline
keywordNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.7/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden. It transparently describes that online templates may reference missing nodes/models and that installation is not required for browsing. However, it does not explicitly confirm non-destructive behavior, though implied.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with multiple focused sentences—no wasted words. It front-loads the purpose and then details the sources. Could be slightly more compact, but still efficient.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that an output schema exists (not shown), the description fully covers tool behavior, parameter semantics, usage guidance, and limitations. It is complete for a search tool with two simple parameters.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, but the description fully compensates by explaining the 'source' parameter options (online vs installed) and their meaning, and that 'keyword' matches against name+title+description. This adds value beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description explicitly states it searches workflow templates from two distinct sources, with a clear verb ('search') and resource. It also distinguishes itself from sibling 'get_template' by positioning it as a follow-up step.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit guidance on when to use each source: 'online' for the official catalog (browsed without installation) and 'installed' for guaranteed runnable templates. Advises to fetch with get_template and reconcile against object_info for online templates.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

submit_workflowA

Queue an API-format workflow for execution (loop step 2: RUN).

workflow is the flat API/prompt-format dict: {node_id: {class_type, inputs}}. Do NOT pass litegraph/UI format here.

On success: returns the prompt_id — then call get_result to fetch outputs and get_image to LOOK at them. Running with zero errors means the graph is VALID, not CORRECT — you still have to inspect the pixels. On failure: returns node_errors keyed by node id. That is NOT an iteration — read the error, fix that specific node, and re-submit until it executes.

ParametersJSON Schema
NameRequiredDescriptionDefault
workflowYes
client_idNocomfy-mcp

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.9/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description fully compensates. Details both success (returns prompt_id) and failure (node_errors) outcomes. Explains that zero errors means graph is VALID but not CORRECT, requiring pixel inspection.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Description is front-loaded with purpose, uses bullet-like structure for failure handling. Every sentence adds value; no filler. Efficiently conveys complex information in a compact form.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Completely covers usage context within a workflow system, referencing necessary post-execution steps and sibling tools. Output schema exists, so return values need not be described. All essential behavioral aspects are addressed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema has 0% description coverage; description adds critical meaning for 'workflow' parameter (flat API dict format). 'client_id' is not elaborated but has a default. Description greatly enhances understanding of the primary parameter.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states the tool queues an API-format workflow for execution (loop step 2: RUN). Specifies the input format as flat API/prompt-format dict, distinguishing it from litegraph/UI format. Action and resource are explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit guidance: on success call get_result/get_image, on failure read node_errors and fix specific node. Also warns against passing wrong format. Clearly differentiates from sibling tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

system_statsA

Report device / VRAM usage — useful when tuning resolution/batch or after an OOM.

ParametersJSON Schema
NameRequiredDescriptionDefault

No parameters

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided; description fully carries behavioral disclosure. 'Report' implies read-only, no side effects mentioned. Transparent enough for a monitoring tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence, front-loaded, no wasted words. Highly concise and structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Has output schema (unknown richness). Description covers purpose and usage scenarios completely for a simple stat reporter. Could add more detail on output format but not necessary.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

No parameters; description adds no param info beyond schema, but baseline for 0 params is 4. Schema coverage is 100%, so no gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states it reports device/VRAM usage, provides specific use cases (tuning resolution/batch, after OOM). Distinguishes from 30+ sibling tools as the only system stats reporter.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly mentions when to use (tuning, after OOM), giving clear context. No explicit when-not-to-use or alternatives, but context is sufficient for the tool's scope.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

template_slotsA

List a template's overridable inputs WITHOUT loading the full graph JSON.

Converts the template to API format and reports each node's literal (non-wired) inputs and current values — the curated parameter list you can change with run_template. Far smaller than the raw graph. Subgraph/unknown nodes can't be expanded and are reported (their inputs aren't overridable this way).

ParametersJSON Schema
NameRequiredDescriptionDefault
nameYes
packNo
sourceNoonline

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries full burden. It discloses conversion to API format, reports literal inputs and current values, and identifies limitations for subgraph/unknown nodes. However, it does not mention potential side effects, authentication needs, or rate limits, missing some behavioral context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences, front-loaded with the primary purpose. Each sentence adds value: first sentence states core function, second explains process, third details boundaries. No redundancy or wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

While the description explains output and limitations well, it completely omits parameter semantics. Given zero schema coverage, this omission makes the tool's input interface opaque. An output schema exists (not provided), so return values are not required, but parameter documentation is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0% and the description fails to explain any of the three parameters ('name', 'pack', 'source'). The description focuses entirely on output behavior, leaving parameter meaning undefined. This is a critical gap for agent invocation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description begins with a clear verb ('List') and resource ('a template's overridable inputs'), immediately stating the tool's core function. It distinguishes itself from siblings like 'get_template' by emphasizing it avoids loading full graph JSON, and explicitly links to 'run_template' for subsequent parameter changes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly tells when to use this tool ('without loading the full graph JSON', 'far smaller than the raw graph') and when not to use it ('Subgraph/unknown nodes can't be expanded', 'their inputs aren't overridable this way'). It also names the sibling 'run_template' as the next step, providing clear contextual guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

upload_imageA

Upload a local image into ComfyUI's input/ dir so a LoadImage node can use it.

Returns the name to reference in the workflow. (Video nodes like VHS_LoadVideo* read files you place directly in ComfyUI's input/ dir instead.)

ParametersJSON Schema
NameRequiredDescriptionDefault
pathYes
overwriteNo

Output Schema

ParametersJSON Schema
NameRequiredDescription
resultYes

TDQS

A4.2/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries full burden. It reveals the upload destination and return value, but lacks details on overwrite behavior (default true) and any limitations. Still reasonably transparent for a simple file upload.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Very concise: two sentences with a parenthetical note. Front-loaded with purpose, no unnecessary words. Every sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given low param coverage and no output schema details, the description covers the core use case but misses parameter explanations. It is adequate but not thorough.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must explain parameters. It implies 'path' is the local file path but does not explicitly define either parameter, especially 'overwrite'. This is insufficient.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'Upload' and the resource 'local image into ComfyUI's input/ dir', and specifies the purpose: so a LoadImage node can use it. It also mentions the return value, making it distinct from sibling tools like 'get_image' or 'install_model'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly tells when to use this tool (for LoadImage node) and when not to (for VHS_LoadVideo* nodes, which read files placed directly in the directory). This provides clear context and alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Tool Schema Changelog

Recent tool additions, removals, and schema changes observed during successful MCP inspections. Dates show when Glama detected each change.

  1. 32 tool updatesv0.2.0
    • First observedcheck_comfyui
    • First observedcompare_images
    • First observedfind_missing_nodes
    • First observedflowzip_to_api
    • First observedget_image
    • First observedget_node
    • First observedget_queue
    • First observedget_result
    • First observedget_template
    • First observedimage_diff_stats
    • First observedinflate_workflow
    • First observedinstall_model
    • First observedinstall_node_pack
    • First observedinterrupt
    • First observedlist_models
    • First observedlist_nodes
    • First observedloop_best
    • First observedloop_finish
    • First observedloop_ledger
    • First observedloop_record
    • First observedloop_report
    • First observedloop_start
    • First observedmeasure_image
    • First observedrestart_comfyui
    • First observedrun_template
    • First observedsave_workflow
    • First observedsearch_models
    • First observedsearch_templates
    • First observedsubmit_workflow
    • First observedsystem_stats
    • First observedtemplate_slots
    • First observedupload_image

TDQS

B3.4/5.0
Disambiguation4/5

Most tools have clearly distinct purposes, but there is minor overlap between compare_images and image_diff_stats (both compare images, though one visual and one statistical) and between get_node (no description) and other tools. Overall, agents can distinguish them.

Naming Consistency5/5

All 32 tools follow a consistent verb_noun pattern with lowercase and underscores (e.g., check_comfyui, find_missing_nodes, loop_start). No mixing of conventions.

Tool Count4/5

32 tools is on the high side, but each tool serves a specific function in the ComfyUI loop workflow, including operations, installation, looping, and evaluation. Could be slightly reduced, but still appropriate for the scope.

Completeness5/5

The tool set covers the entire loop workflow end-to-end: start, run, evaluate, compare, record, finish, plus supporting operations for node/model management and template handling. No obvious gaps for the stated purpose.

Maintenance

ActivityActive
ResponsivenessSyncing

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