ClearMarket

ClearMarket

Institutional reference layer for prediction market data. Structures, classifies, grades, and links markets across Polymarket and Kalshi so research, risk, and data teams can use them like any other asset class.

Live now: clearmarket.fyi · REST api.clearmarket.fyi/v1 · MCP api.clearmarket.fyi/mcp · daily wire feed at /signals. Open and read-only — no key required.

Coverage: the live Kalshi + Polymarket universe (untraded placeholder slots excluded; counts on the site refresh with each ingest). Every market carries a Resolution Clarity Grade (RCG A/B/C) and full source provenance — the resolution source is named where the venue commits to one, and where it doesn't, that absence is classified and graded (that gap is the point). Markets listing the same question on both venues carry cross-venue links. Prices refresh hourly.

v0.2 · June 2026

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Quickstart

No key, no signup — open and read-only.

# REST — search the graded universe

curl -s "https://api.clearmarket.fyi/v1/events?q=fed"

one event, fully graded (markets + resolution provenance + cross-venue links)

curl -s "https://api.clearmarket.fyi/v1/events/kxfed-26jul"

the daily CM Signal wire feed

curl -s "https://clearmarket.fyi/signals.json"

MCP (agent clients — Claude Desktop, Cursor, VS Code): streamable HTTP at https://api.clearmarket.fyi/mcp, six read-only tools (list_events, get_event, get_market, list_upcoming_catalysts, list_signals, get_signal). get_market accepts a ClearMarket id, a venue-native id/ticker, or a market URL (best-effort — Kalshi URLs resolve; for Polymarket pass the conditionId); get_event takes detail=concise for a lean grade/price view of large multi-market events. Agent manifest at /AGENTS.md. One-click install:

# Claude Code

claude mcp add --transport http clearmarket https://api.clearmarket.fyi/mcp

…or add it by hand:

// claude_desktop_config.json  /  ~/.cursor/mcp.json

{ "mcpServers": { "clearmarket": { "command": "npx", "args": ["-y", "mcp-remote", "https://api.clearmarket.fyi/mcp"] } } }

Every URL also ships a parallel .json, embedded JSON-LD, and a row in /llms.txt — agents never have to scrape HTML.

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Does the grade predict resolution risk? A 7,166-contract backtest

A prediction-market contract can be right about the event and still settle on the fine print. The Resolution Clarity Grade scores that resolution risk from the rules text alone, before a market resolves, on every Kalshi and Polymarket contract. Tested against Polymarket's public on-chain dispute record (data as of 2026-07-23):

52 of the 55 disputed contracts had been graded C before they resolved. C-rated contracts were challenged at about 20 times the rate of A and B combined (relative risk 20.6x, 95% CI 6.4x to 65.8x). The separation holds within trading-volume quartiles (top quartile: A+B 0.22% vs C 4.94%), so the grade is not a proxy for market size. All three challenges to A-rated contracts failed. Pre-registered dispute definition, Wilson intervals, the volume control and the source-commitment cut are in docs/BACKTEST.md; the dataset is committed at data/backtest/ and every number reproduces with one command and no API key:

python3 scripts/backtest_stats.py data/backtest/dispute-labels-2026-07-23.csv

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The problem

Polymarket and Kalshi publish market data that is useful for retail trading but not ingestion-ready for institutional research or risk. Three gaps a buyer hits immediately:

1. You can't tell where the resolution data comes from. On ~65% of institutional-category Polymarket markets by count — ~80% dollar-weighted — the venue commits to no named resolution source (placeholder language like "a consensus of credible reporting", or non-binding hedges). Kalshi names sources but sometimes loosely ("for example, Google Finance" on S&P 500 contracts).
2. The same event is priced differently on each platform. Polymarket lists the Fed April 2026 rate decision as four directional yes/no questions; Kalshi lists eleven rate-level brackets. Nothing in either API tells you they are pricing the same thing.
3. Related markets aren't grouped, on a single platform or across them. Nine Polymarket contracts on when the Iran conflict ends sit in the API as nine separate items, with nothing connecting them. Cross-platform, the gap is wider still.

Institutions solving any of these gaps in-house end up with one-off parses that do not generalize. ClearMarket ships a normalized schema, an enrichment pipeline, and machine-readable specimens you can diff against.

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Before and after

What the platforms give you

Polymarket on the April 2026 Fed rate decision (1 of 4 directional markets):

{

"question": "Will the Fed decrease interest rates by 50+ bps after the April 2026 meeting?", "endDate": "2026-04-30T23:00:00Z", "resolutionSource": "", "volume": 1530000, "description": "This market will resolve 'Yes' if ... [rules embedded in prose]" }

Kalshi on the same Fed decision (1 of 11 strike markets):

{

"ticker": "KXFED-26APR-T3.25", "title": "Will the upper bound of the federal funds rate be above 3.25%...", "close_time": "2026-04-29T17:55:00Z", "rules_primary": "If the upper bound of the target federal funds rate... [prose]", "settlement_sources": [{"name": "Federal Reserve Board of Governors", "url": "..."}] }

Empty resolutionSource. Rules buried in prose. No catalyst calendar. And nothing telling you these are two of fifteen markets pricing the same Fed meeting.

What ClearMarket gives you

{

"event_id": "CM-EVT-KXFED26APR", "slug": "kxfed-2026-apr", "question": "What will the Fed announce at the April 2026 FOMC meeting?", "category": "macro",

// events are single-venue; this is Kalshi's bundle of the decision "venues_covered": ["kalshi"],

// shared labels for searching across the universe "tags": ["macro", "fed-rate-decisions", "fomc", "monetary-policy"],

// real-world events that move the price "catalyst_dates": [ {"date": "2026-04-29", "type": "fomc", "label": "FOMC meeting Day 1"}, {"date": "2026-04-30", "type": "fomc", "label": "FOMC statement + press conference"} ],

"markets": [ { "market_id": "CM-MKT-KXFED26APR-T325", "question_id": "CMX-FED26APR-UB325", // the venue-independent question "rcg": {"grade": "A"}, "resolution": {"source": "Federal Reserve Board of Governors", "arbitration_model": "kalshi_staff"}, // the same question priced on the other venue "also_on": [{"venue": "polymarket", "market_id": "CM-MKT-0xA1B2", "price": 0.62}] } ],

"editorial_notes": "Kalshi prices this decision as eleven rate-level strike markets; Polymarket as four directional questions. They are separate single-venue events; ClearMarket links the matching questions across them by question_id (surfaced as also_on)." }

Two single-venue events — one Kalshi, one Polymarket — each graded, each on the FOMC catalyst calendar, with the Federal Reserve named as the source. The matching questions are linked across venues by a shared question_id, and each market's also_on surfaces its twin on the other venue with a live price.

Full record at samples/fed-apr-2026/specimen.json — a legacy combined-bundle specimen captured before the single-venue split; the live API now serves these as two single-venue events linked by question_id.

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What's here

The live product (site, REST API, MCP, daily wire feed) serves the full live universe. This repo is the open schema + enrichment pipeline + reference specimens behind it:

• JSON Schemas for the four ClearMarket tables (events, markets, marks, resolution_log)
• Postgres DDL matching the schemas
• An Enhancement Script (enhance.py) that transforms raw Polymarket + Kalshi API pulls into ClearMarket-shaped records, with AI-drafted editorial enrichment
• Reference specimens (15 canonical events, 55 markets) you can diff against — the worked examples below
• The CFTC ANPRM comment (cftc-anprm/) — the cross-venue resolution-divergence analysis filed with the Commission (RIN 3038-AF65)

All specimens validate against the JSON Schemas. All records carry per-field field_provenance flagging whether a value came from the platform API, ClearMarket editorial, a derived computation, an imputed proxy, or a known venue limitation.

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The four specimens

Open any samples/ /specimen.json for the full bundle. The top-level _meta.editorial_review_notes block lists every AI-drafted field and the rules that govern them.

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The wedge in one sentence

ClearMarket is the independent enrichment layer above those feeds. It parses what the platforms don't publish in structured form: canonical questions, authoritative data sources, parsed resolution structures, cross-platform linkage, thematic families, and per-field provenance.

Two products sit on top of the same schema (a third is on the roadmap):

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Architecture

Three steps. The first two are deterministic Python; the third is the editorial layer that platforms do not ship.

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│ 1. INGESTION (