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by io.github.pipeworx-io

Polymarket–Kalshi Spread

polymarket_kalshi_spread
Read-onlyIdempotent

Cross-venue spread between Kalshi and Polymarket for the same resolving question. The two venues sometimes price the same outcome 2-25pp apart because their participant pools differ — when the bet shapes are equivalent that delta is a real signal, when they aren't the tool says so. TWO MODES: (1) topic — 10 pre-mapped macro shortcuts ("fed", "btc", "cpi", "gdp", "sp500", "recession", "next_pope", "next_uk_pm", "next_israel_pm", "2028_president") auto-fetch the matching event on each venue. (2) explicit kalshi_event_ticker + polymarket_event_slug for custom pairings — BOTH modes run the identical token-overlap matcher, so the same disclosures apply to both. RESPONSE: each venue's leg-by-leg prices (raw probability 0-1) plus matched spread[].top_spreads_pp (Kalshi − Polymarket) where the same outcome shows up on both sides. SAFETY FIELDS: compatibility_warning is a sentence and compatibility_codes[] the machine-readable form; BOTH can be non-empty on returned pairs, so read them even when matched_pairs>0. Codes: event_subject_mismatch (the two event titles share no subject words — probably not the same question), temporal_mismatch (they resolve in different months), temporal_alignment_unknown (the resolution month could not be parsed on one or both sides — NOT the same as confirmed-aligned; check each event's close/strike date yourself), non_equivalent_bet_shapes, no_candidate_pairs, unclassified_legs_excluded, pairing_unverified (set in EITHER mode whenever pairs are returned: the legs were matched by keyword and word overlap, not a shared resolution source). Each entry in top_spreads_pp carries its own flags[] (temporal_mismatch, temporal_alignment_unknown, event_subject_mismatch, low_token_overlap). A leg whose metric_type or match_subtype is "unknown" is NEVER paired — those comparisons land in spread.skipped_unclassified and, when the wording lined up, in spread.low_confidence_pairs[] for inspection only. temporal_alignment{polymarket_month,kalshi_month,aligned} tells you whether the two events resolve in the same calendar period, in EITHER mode; null means it could not be computed (see temporal_alignment_unknown), not that the two sides align. spread.fees_note is a standing disclosure: Kalshi charges per-contract trading fees, Polymarket does not, and this tool does not model Kalshi's fee schedule — every spread_pp is gross, not a net tradeable edge. skipped_cross_type / skipped_cross_subtype counters expose how many leg-pair comparisons were dropped (cross-type = metric_type mismatch like MoM vs YoY; cross-subtype = inequality mismatch like cum_ge vs cum_le). Real cross-venue spreads are rarer than the macro-shortcut list suggests — most pre-mapped topics return compatibility_warning today; pre-mapped ≠ tradeable.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
topicNoPre-mapped: fed | btc | cpi | gdp | sp500 | recession | next_pope | next_uk_pm | next_israel_pm | 2028_president
kalshi_event_tickerNoExplicit Kalshi event ticker, e.g. "KXFED-26OCT". Overrides the topic-mapped Kalshi side.
polymarket_event_slugNoExplicit Polymarket event slug, e.g. "fed-decision-in-june-825". Overrides the topic-mapped Polymarket side.

Schema Changelog

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

  1. Changed1 schema field changed
    • addedInput schema / examples
      Added value: +[
+  {
+    "topic": "fed"
+  },
+  {
+    "topic": "btc"
+  }
+]
  2. Added

TDQS

A4.3/5.0
Behavior5/5

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

The description goes well beyond the annotations: it explains compatibility_codes semantics, non-equivalent bet shapes, skipped leg handling, temporal_alignment null meaning, gross-vs-net fee treatment, and the standing pairing_unverified caveat. Nothing contradicts the readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false annotations; the extra disclosure reinforces them.

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 long but well front-loaded: purpose, modes, response shape, safety fields, and limitations appear in logical order with clear uppercase labels. The density is justified for a complex tool with no output schema, though it could be slightly tightened per topic with bullet-like formatting.

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 and only sparse parameter metadata, the description carries the full explanatory burden and succeeds: it covers response semantics, compatibility warnings, skipped leg counters, fee caveats, temporal alignment null behavior, and the current caveat about pre-mapped topics. An agent has enough to invoke the tool and interpret its results correctly.

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 documents all three parameters with 100% coverage, so the baseline is 3. The description adds non-obvious value by stating that both modes run the identical token-overlap matcher, that explicit parameters override the topic-mapped side, and that pre-mapped topics do not guarantee tradeable spreads.

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 opening sentence defines the deliverable precisely: a cross-venue spread between Kalshi and Polymarket for the same resolving question, and the following sentence clarifies when that delta is meaningful. It is clear and distinct from generic arb/edge tools, but it does not explicitly name or differentiate against a sibling like polymarket_arbitrage.

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 mode selection: use `topic` shortcuts for pre-mapped macro events, or provide explicit `kalshi_event_ticker` and `polymarket_event_slug` for custom pairings. It also warns that most pre-mapped topics currently return compatibility_warning, giving practical usage caution, though it never directly contrasts this tool with sibling alternatives.

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

A4.1/5.0
Disambiguation4/5

Most tools have clearly distinct purposes, but the multiple 'ask' variants (ask_pipeworx, ask_pipeworx_grounded, deep_research) and discovery tools (discover_tools, suggest_questions) could cause confusion. Descriptions help differentiate, but the overlap is notable.

Naming Consistency4/5

All tool names use lowercase with underscores, but there is a mix of verb-first (e.g., ask_pipeworx, fetch_indicator) and noun-first (e.g., ai_visibility_check, polymarket_arbitrage) patterns. Consistent style but varied structure.

Tool Count2/5

33 tools is excessive for a coherent set. The server covers diverse domains (data lookup, betting, memory, subscriptions, web generation, package scanning) without a clear unifying theme, making it feel like a collection of utilities rather than a focused tool surface.

Completeness3/5

Core data retrieval and research capabilities are well-covered, but there are notable gaps such as lack of data update tools for OWID and no direct visualization. Additionally, the betting tools are extensive while other areas like entity editing are missing.

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