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AceDataCloud

mcp-webextrator

by AceDataCloud

webextrator_render

Render a web page in a headless browser and return the fully rendered HTML after JavaScript executes. Use it to inspect dynamic content and SPAs.

Instructions

Render a web page and return the fully rendered HTML.

Uses a headless browser to navigate to the specified URL, waits for JavaScript
to execute, and returns the final rendered HTML source.

Use this when:
- You need the fully rendered HTML of a JavaScript-heavy page
- You want to inspect the DOM after dynamic content has loaded
- You need to capture single-page application (SPA) content

Returns:
    By default, the rendered HTML content inline. With async=true, a JSON
    envelope with a `task_id` — poll `webextrator_get_task` until it reports
    `finished_at`, then read the rendered HTML from its `response`.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
urlYesThe URL of the web page to render. Required.
asyncNoWhether to process the request asynchronously.
delayNoExtra delay in seconds after page load before capturing HTML.
headersNoExtra HTTP headers to include with the page request.
timeoutNoTotal timeout in seconds for page load. Default is 30.
user_agentNoOverride the User-Agent header for the page request.
wait_untilNoPage load wait condition before capturing HTML. Options: 'load', 'domcontentloaded', 'networkidle', 'commit'. Default is 'networkidle'.
callback_urlNoCallback URL for async processing. If provided, the task runs asynchronously and results are sent to this URL when complete.
block_resourcesNoResource types to block during page load to speed up rendering. Options: 'image', 'font', 'media', 'stylesheet', 'xhr', 'fetch'.
wait_for_selectorNoCSS selector to wait for before capturing HTML.

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections. Dates show when Glama detected each change.

  1. Changed5 schema fields changedv0.1.7
    • addedInput schema / properties / async
      Added value: +{
      +  "anyOf": [
      +    {
      +      "type": "boolean"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "default": null,
      +  "description": "Whether to process the request asynchronously.",
      +  "title": "Async"
      +}
    • removedInput schema / properties / bypass_cache
      Removed value: -{
      -  "anyOf": [
      -    {
      -      "type": "boolean"
      -    },
      -    {
      -      "type": "null"
      -    }
      -  ],
      -  "default": null,
      -  "description": "Skip the Redis result cache for this request (still writes the fresh result back). Default is false.",
      -  "title": "Bypass Cache"
      -}
    • removedInput schema / properties / cache_ttl_seconds
      Removed value: -{
      -  "anyOf": [
      -    {
      -      "type": "number"
      -    },
      -    {
      -      "type": "null"
      -    }
      -  ],
      -  "default": null,
      -  "description": "Override the global cache TTL (seconds) for this entry. 0 means do not cache this response. Default is 3600.",
      -  "title": "Cache Ttl Seconds"
      -}
    • removedInput schema / properties / cookies
      Removed value: -{
      -  "anyOf": [
      -    {
      -      "items": {
      -        "additionalProperties": true,
      -        "type": "object"
      -      },
      -      "type": "array"
      -    },
      -    {
      -      "type": "null"
      -    }
      -  ],
      -  "default": null,
      -  "description": "Cookies to install before navigation. Each cookie is an object with at least 'name' and 'value', plus optional 'domain', 'path', 'expires', 'httpOnly', 'secure', 'sameSite'. Useful for authenticated pages.",
      -  "title": "Cookies"
      -}
    • removedInput schema / properties / mode
      Removed value: -{
      -  "anyOf": [
      -    {
      -      "enum": [
      -        "sync",
      -        "async"
      -      ],
      -      "type": "string"
      -    },
      -    {
      -      "type": "null"
      -    }
      -  ],
      -  "default": null,
      -  "description": "Processing mode. Defaults to API sync behavior. Pass 'async' to return immediately with a task_id to poll via webextrator_get_task.",
      -  "title": "Mode"
      -}
  2. Changed1 schema field changedv0.1.5
    • changedInput schema / properties / mode / description
      Previous value: -"Processing mode. Defaults to 'async': returns immediately with a task_id to poll via webextrator_get_task. Pass 'sync' to wait for the result inline (may time out on slow pages)."New value: +"Processing mode. Defaults to API sync behavior. Pass 'async' to return immediately with a task_id to poll via webextrator_get_task."
  3. Changed1 schema field changedv0.1.3
    • changedInput schema / properties / mode / description
      Previous value: -"Processing mode. 'sync' (default) waits for the result; 'async' returns immediately with a task_id to poll via the Tasks API."New value: +"Processing mode. Defaults to 'async': returns immediately with a task_id to poll via webextrator_get_task. Pass 'sync' to wait for the result inline (may time out on slow pages)."
  4. Changed4 schema fields changedv0.1.2
    • addedInput schema / properties / bypass_cache
      Added value: +{
      +  "anyOf": [
      +    {
      +      "type": "boolean"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "default": null,
      +  "description": "Skip the Redis result cache for this request (still writes the fresh result back). Default is false.",
      +  "title": "Bypass Cache"
      +}
    • addedInput schema / properties / cache_ttl_seconds
      Added value: +{
      +  "anyOf": [
      +    {
      +      "type": "number"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "default": null,
      +  "description": "Override the global cache TTL (seconds) for this entry. 0 means do not cache this response. Default is 3600.",
      +  "title": "Cache Ttl Seconds"
      +}
    • addedInput schema / properties / cookies
      Added value: +{
      +  "anyOf": [
      +    {
      +      "items": {
      +        "additionalProperties": true,
      +        "type": "object"
      +      },
      +      "type": "array"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "default": null,
      +  "description": "Cookies to install before navigation. Each cookie is an object with at least 'name' and 'value', plus optional 'domain', 'path', 'expires', 'httpOnly', 'secure', 'sameSite'. Useful for authenticated pages.",
      +  "title": "Cookies"
      +}
    • addedInput schema / properties / mode
      Added value: +{
      +  "anyOf": [
      +    {
      +      "enum": [
      +        "sync",
      +        "async"
      +      ],
      +      "type": "string"
      +    },
      +    {
      +      "type": "null"
      +    }
      +  ],
      +  "default": null,
      +  "description": "Processing mode. 'sync' (default) waits for the result; 'async' returns immediately with a task_id to poll via the Tasks API.",
      +  "title": "Mode"
      +}
  5. First observedv0.1.0

TDQS

A4.3/5.0
Behavior4/5

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

With no annotations provided, the description carries the full behavioral disclosure burden. It explains the headless-browser mechanism, JavaScript execution wait, and the inline vs. async return behavior, including polling instructions via webextrator_get_task. It does not cover error cases, rate limits, or security implications of executing JS, but the core behavior is transparently described.

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 appropriately sized and front-loaded: a one-line summary, a brief mechanism sentence, a compact 'Use this when' list, and a Return section. Every sentence earns its place, and the structure makes it skimmable for an agent.

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 output schema exists and the input schema has 100% coverage, the description effectively fills the remaining gaps: async processing, task polling flow, and primary use cases. It also cross-references the sibling polling tool, making the complete call-and-retrieve workflow clear without requiring schema inspection.

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 100%, so the baseline is 3 even though the free-text description adds no per-parameter detail. The description's async explanation and return-format notes are helpful context but not parameter semantics; the schema already documents all parameters, defaults, and enums.

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 opens with a specific verb and resource: 'Render a web page and return the fully rendered HTML.' It clearly distinguishes the tool from siblings like webextrator_extract by focusing on full-page rendering rather than data extraction, and it reinforces the purpose with concrete use cases (JavaScript-heavy pages, DOM inspection, SPA content).

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 'Use this when' bullet list gives explicit scenarios for when the tool is appropriate, such as needing fully rendered HTML after dynamic content loads. However, it does not explicitly state when not to use it or name alternative siblings like webextrator_extract for non-rendering extraction tasks, so the exclusionary guidance is missing.

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

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