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by io.github.pipeworx-io

Polymarket Arbitrage

polymarket_arbitrage
Read-onlyIdempotent

Find arbitrage opportunities on Polymarket via monotonicity violations + partition-sum checks. Call with NO args for a trending_scan of the top ~200 markets by weekly volume; pass event for the strongest per-event partition_check, or topic for a themed cross-event scan. event (recommended for a specific market): pass a Polymarket event slug like "fed-decision-may-2026" or "when-will-bitcoin-hit-150k"; walks child markets, checks date-axis / threshold-axis ordering AND computes the partition_check (sum of YES prices across mutually-exclusive legs — should ≈1; deviations >3pp emit a BUY/SELL EVERY LEG signal). topic (for cross-event scanning): pass a seed question like "Strait of Hormuz traffic returns to normal" or "Fed rate decision"; searches related events across the platform, flattens markets, runs the comparator on the union. Cross-event mode catches "...by May 31" vs "...by Jun 30" patterns that single-event misses. SEMANTIC ANCHOR: cross-event pairs require ≥0.30 Jaccard similarity on question tokens (prevents Powell-Fed-Pause being paired with Powell-DOJ-probe); skipped_low_similarity surfaces the rejected pair count. PARTITION FILTER: drops will-person-X / will-manager-Y / will-someone-else- placeholder slugs; partitions with >20% placeholder fraction return null arb signal. Response: opportunities[] (gap_pp, suggested_trade, reasoning, monotonicity violation context), and in event mode partition_check{sum_yes_prices, gap_from_1, placeholders_filtered, suggested_trade}. FILL CHECK: when the partition signal fires, arbitrage.fill_check prices it against live CLOB depth (theoretical_edge_pp_at_book vs realizable_edge_pp at 1000 shares/leg, thin_legs[]) — realizable_edge_pp ≤ 0 means the overround exists only at last-trade, not in the book; do not trade it. For custom sizing use polymarket_fill_risk.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
eventNoSingle-event mode (use this if you know the specific Polymarket event): event slug like "fed-decision-may-2026" or "when-will-bitcoin-hit-150k". Full Polymarket URLs also accepted.
topicNoCross-event mode (use this if you want to scan related events across the platform): a topic or seed question like "Fed rate decision" or "Strait of Hormuz traffic returns to normal". Tool searches Polymarket for related events and checks monotonicity across them.

Schema Changelog

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

  1. Changed1 schema field changed
    • removedInput schema / anyOf
      Removed value: -[
-  {
-    "required": [
-      "event"
-    ]
-  },
-  {
-    "required": [
-      "topic"
-    ]
-  }
-]
  2. Changed3 schema fields changed
    • addedInput schema / anyOf
      Added value: +[
+  {
+    "required": [
+      "event"
+    ]
+  },
+  {
+    "required": [
+      "topic"
+    ]
+  }
+]
    • changedInput schema / properties / event / description
      Previous value: -"Single-event mode: Polymarket event slug (e.g. \"when-will-bitcoin-hit-150k\") or full URL."New value: +"Single-event mode (use this if you know the specific Polymarket event): event slug like \"fed-decision-may-2026\" or \"when-will-bitcoin-hit-150k\". Full Polymarket URLs also accepted."
    • changedInput schema / properties / topic / description
      Previous value: -"Cross-event mode: a topic or seed question. Tool searches Polymarket for related markets across separate events and checks monotonicity across them. E.g. \"Strait of Hormuz traffic returns to normal\"."New value: +"Cross-event mode (use this if you want to scan related events across the platform): a topic or seed question like \"Fed rate decision\" or \"Strait of Hormuz traffic returns to normal\". Tool searches Polymarket for related events and checks monotonicity across them."
  3. First observed

TDQS

A4.8/5.0
Behavior5/5

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

Annotations already indicate read-only and idempotent behavior, but the description adds extensive behavioral nuance: the semantic anchor threshold (Jaccard ≥0.30), the partition filter with placeholder fraction >20% returning null, the fill check against live CLOB depth, and explicit guidance 'do not trade it' when realizable_edge_pp ≤0. This is highly transparent about internal logic and failure conditions.

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 lengthy and packed with detail, but nearly every sentence carries unique information essential to using the tool correctly (modes, thresholds, response structure, fill check). The use of capital labels (SEMANTIC ANCHOR, PARTITION FILTER, FILL CHECK) improves parseability. It is appropriately structured for the complexity, though slightly verbose.

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?

With no output schema, the description fully explains the return shape ('opportunities[]', 'partition_check', 'skipped_low_similarity', 'theoretical_edge_pp_at_book', 'realizable_edge_pp', 'thin_legs[]') and covers edge cases (placeholders, low similarity, no-arg scan). It also mentions the companion tool for custom sizing, making it contextually self-sufficient. This is as complete as a description can be for such a complex 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?

The schema already describes both event and topic well, so the baseline is high. The description enhances this with concrete slug examples (e.g., 'fed-decision-may-2026'), clarifies that full URLs are also accepted, and explicitly contrasts the two parameter modes. It adds meaningful usage context beyond the schema, warranting a 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?

The description opens with a precise verb+resource statement ('Find arbitrage opportunities on Polymarket via monotonicity violations + partition-sum checks'), clearly differentiating it from siblings like polymarket_edges or polymarket_fill_risk. It goes on to specify distinct modes (trending_scan, event, topic), making the tool's purpose unambiguous.

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 each mode: 'Call with NO args for a trending_scan', 'event (recommended for a specific market)', 'topic (for cross-event scanning)'. It also names an alternative tool for custom sizing ('use polymarket_fill_risk'), and provides concrete example inputs, giving the agent clear decision criteria.

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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TDQS

A3.9/5.0
Disambiguation3/5

Several tool clusters overlap: ask_pipeworx/ask_pipeworx_beta/ask_pipeworx_grounded/deep_research all route to the same source catalog, the six Polymarket tools have fuzzy boundaries between research, edge scanning, arbitrage, and fill checking, and available vs quote_list both enumerate B3 tickers. The descriptions are detailed and try to differentiate, but an agent could still easily pick the wrong meta-tool.

Naming Consistency4/5

The overwhelming majority follow lower_snake_case verb_noun naming (ask_pipeworx, resolve_entity, scan_dependency, validate_claim, list_subscriptions). Deviations like available, quote, crypto, currency, inflation, and prime_rate are bare nouns, and forget is a lone verb, but the convention remains readable and largely predictable.

Tool Count2/5

38 tools is excessive for what the server name (Brapi) suggests, and the set spans unrelated domains: Brazilian market data, a 5,798-tool universal data router, Polymarket betting analytics, memory, subscriptions, AI visibility, npm dependency scanning, and llms.txt generation. The count crosses the 25+ threshold and dilutes the server's focus.

Completeness4/5

Within each sub-domain the surface is fairly complete: brapi.dev quotes/directory/rates, Pipeworx routing/grounding/research/entity resolution/validation, prediction-market arbitrage/fill checks, memory CRUD, and subscription lifecycle all cover their core workflows. Minor gaps exist, such as no dedicated historical stock-price series beyond quote's OHLC window and deep_research requiring an account, but agents can work around them.

Resources