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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 far beyond the readOnly/idempotent annotations, disclosing that the tool does not model Kalshi's fee schedule, that returned spreads are gross not net, that pairs are matched by keyword overlap rather than a shared resolution source, and that unknown-type legs are never paired. It also enumerates every compatibility code and explains that compatibility fields can be non-empty even when matched_pairs>0. None of this contradicts the 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 long and dense, reflecting the tool's complexity, but it is organized with labeled sections (RESPONSE, SAFETY FIELDS, Codes) and front-loads the core purpose before diving into details. Some sentences are packed with many clauses and could be tightened into lists, but each piece of information is pertinent to correct usage, so the length is largely justified.

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 present, the description shoulders the full burden of explaining return values and edge cases, and it does so thoroughly: it covers spread structure, top_spreads_pp flags, compatibility_codes, temporal_alignment semantics (including null meaning), skipped_unclassified, skipped counters, and fees_note. It also addresses real-world failure modes such as pre-mapped topics yielding warnings. An agent has everything needed 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?

Schema coverage is 100%, so the baseline is 3, but the description adds real semantic value beyond the schema: it explains that topic auto-fetches the matching event on each venue, that explicit tickers/slugs override the topic-mapped side, and that both modes run the identical token-overlap matcher. This clarifies parameter behavior and interplay better than the raw property descriptions alone.

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 opens with a specific verb and resource: 'Cross-venue spread between Kalshi and Polymarket for the same resolving question.' It clearly identifies the tool's function and the two distinct invocation modes, and it is unambiguous about the domain. However, it never explicitly contrasts itself with sibling tools like polymarket_arbitrage or polymarket_edges, so it stops short of full sibling differentiation.

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 on when to use each mode: topic shortcuts for 10 pre-mapped macros, and explicit kalshi_event_ticker + polymarket_event_slug for custom pairings. It also manages expectations by warning that most pre-mapped topics return a compatibility_warning today and that pre-mapped ≠ tradeable. It does not, however, give explicit guidance on choosing this tool over sibling tools, so it lacks a direct alternatives discussion.

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

A3.7/5.0
Disambiguation2/5

Many tools have overlapping purposes, e.g., multiple Polymarket analysis tools, several query tools (ask_pipeworx, deep_research, compare_entities, entity_profile) with unclear boundaries. Agents may struggle to choose the correct tool.

Naming Consistency3/5

While most names use snake_case, there is no consistent prefix pattern across subdomains (e.g., 'ask_', 'get_', 'polymarket_', 'pipeworx_'). Some names like 'bet_research' and 'deep_research' follow different conventions within the same domain.

Tool Count2/5

34 tools is excessive for a server named 'Nws' that primarily suggests weather. The set covers many unrelated domains (prediction markets, npm scanning, memory), making the scope unfocused and overloaded.

Completeness3/5

The server has decent coverage for prediction markets and company financials, but weather tools are limited to basic forecasts/alerts, lacking radar, climate, or historical data. Other domains like npm scanning seem tacked on.

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