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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.

TDQS

A4.6/5.0
Behavior5/5

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

The annotations already declare this tool read-only and idempotent, and the description adds extensive non-obvious behavior: spreads are gross because Kalshi fees are not modeled, compatibility_codes can be non-empty even when pairs are returned, temporal_alignment null means unknown rather than aligned, and unknown leg types are never paired. This is exactly the contextual detail an agent needs to trust the result.

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 organized into clear sections: modes, response shape, safety fields, flag meanings, fees, and skipped comparisons. Every block adds useful information, though it is verbose and repeats the point that both modes use the same matcher.

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 compensates by explaining leg prices, top_spreads_pp, compatibility fields, per-pair flags, temporal_alignment semantics, the fees caveat, and skipped-comparison counters. It also manages expectations about pre-mapped topics, so an agent can call the tool without needing extra documentation.

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, and the description adds the relationship between them: topic selects a pre-mapped macro shortcut while kalshi_event_ticker and polymarket_event_slug override the topic-mapped side. It could be clearer that a custom pairing likely requires both explicit parameters together, but the core semantics are well explained.

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 resource ('Cross-venue spread between Kalshi and Polymarket for the same resolving question') and clearly states what the tool computes. It also names two distinct modes and the shape of the response, making it impossible to confuse with the standalone Polymarket tools in the sibling list.

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?

It explicitly describes when to use the pre-mapped topic shortcuts versus a custom pairing of kalshi_event_ticker and polymarket_event_slug, and it warns that pre-mapped topics often return compatibility_warning. It never names alternative sibling tools or states when not to use this tool relative to them, so it stops short of full exclusion guidance.

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 there is some overlap: ask_pipeworx and ask_pipeworx_grounded are very similar, and the multiple Polymarket tools could be confused. The memory tools (remember, recall, forget) are distinct.

Naming Consistency3/5

Tool names consistently use snake_case, but the pattern is not strictly verb_noun. Some names are descriptive phrases (e.g., scan_competitor_ai_presence), while others are straightforward (e.g., keyword_overview). Overall readable but not highly consistent.

Tool Count3/5

32 tools is on the high side for a single server, but the scope is broad (SEO, finance, FDA, betting, memory). The tool count feels slightly excessive, yet each tool appears justified by its specific use case.

Completeness4/5

The tool set covers a wide range of business research needs: SEO, SEC filings, FDA data, betting analytics, and memory. Minor gaps exist (e.g., no direct social media or HR data), but the coverage is impressive for a general-purpose data server.

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