Event Resolver API

Resolve prediction market events with confidence scores. Aggregates news, price feeds, and web data to determine if real-world events occurred. Settlement oracle for binary, numeric, and categorical outcomes. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.

Quickstart -- MCP

Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):

{
  "mcpServers": {
    "event-resolver": {
      "url": "https://event-resolver.api.klymax402.com/mcp"
    }
  }
}

Quickstart -- HTTP (x402)

curl -X POST "https://event-resolver.api.klymax402.com/api/resolve" \
  -H "Content-Type: application/json" \
  -d '{"question":"..."}'
-> 402 Payment Required, with an x402 payment challenge in the response body

Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.

Tools

| Tool | Method | Path | Price | Description |
|---|---|---|---|---|
| event_resolve_outcome | POST | /api/resolve | $0.005 | Resolve a prediction market event/question. Aggregates multiple data sources to determine outcome with confidence score. |
| event_verify_claim | POST | /api/verify | $0.003 | Quick-verify a factual claim. Returns verdict (true/false/unverifiable) with confidence and evidence. |
| event_check_price_threshold | POST | /api/price-check | $0.002 | Check if a crypto/stock price crossed a threshold. Common prediction market resolution pattern. |

event_resolve_outcome

Use this when you need to determine the outcome of a real-world event for prediction market settlement. Takes a natural language question (e.g. "Did BTC reach $100K?", "Did France win the 2026 World Cup?") and returns a structured resolution with confidence score.

Parameters

| Name | Type | Required | Description |
|---|---|---|---|
| question | string | yes | The event question to resolve, e.g. 'Did BTC reach $100K by April 2026?' or 'Did the Lakers win the NBA Finals 2026?' |
| type | string | no | Type of resolution expected. binary = Yes/No, numeric = a number, categorical = one of several options. Default: binary. |

Returns

- question -- the original question being resolved
- resolved -- whether the event can be conclusively determined (true/false)
- outcome -- the determined result -- "Yes"/"No" for binary, a number for numeric, or a category string
- confidence -- 0-100 score indicating certainty of the resolution
- sources -- array of data sources consulted, each with name, url, and whether it agrees with the outcome
- timestamp -- ISO timestamp of when the resolution was performed

Example response:

{ "question": "Did BTC reach $100K?", "resolved": true, "outcome": "Yes", "confidence": 95, "sources": [{ "name": "CoinGecko", "url": "https://coingecko.com", "agrees": true }], "timestamp": "2026-04-13T12:00:00Z" }

Not for: prediction market odds (use prediction_list_markets), crypto prices only (use token_get_price), full fact checking with sources (use research_check_fact), trust/security scoring (use trust_score_evaluate).

event_verify_claim

Use this when you need to quickly verify whether a factual claim is true or false. Simpler and cheaper than full event resolution -- designed for fast claim checking without structured market settlement.

Parameters

| Name | Type | Required | Description |
|---|---|---|---|
| claim | string | yes | The factual claim to verify, e.g. 'Bitcoin is above $90,000' or 'The US unemployment rate is below 4%' |

Returns

- claim -- the original claim being verified
- verdict -- "true", "false", or "unverifiable" if insufficient data
- confidence -- 0-100 score indicating certainty of the verdict
- evidence -- array of strings summarizing supporting or contradicting evidence found

Example response:

{ "claim": "Tesla stock is above $300", "verdict": "true", "confidence": 90, "evidence": ["CoinGecko/financial APIs confirm current price above threshold", "Multiple news sources corroborate"] }

Not for: prediction market odds (use prediction_list_markets), full fact checking with sources (use research_check_fact), stock prices (use stock_get_quote), crypto prices only (use token_get_price).

event_check_price_threshold

Use this when you need to check if a cryptocurrency or stock price has crossed a specific threshold -- the most common resolution type in prediction markets. Returns current price, whether threshold was crossed, and direction.

Parameters

| Name | Type | Required | Description |
|---|---|---|---|
| asset | string | yes | Asset name or CoinGecko ID (e.g. 'bitcoin', 'ethereum', 'solana', 'dogecoin') |
| threshold | number | yes | Price threshold in USD to check against |
| direction | string | yes | Whether to check if price is above or below the threshold |

Returns

- asset -- the asset being checked (e.g. "bitcoin", "ethereum", "solana")
- currentPrice -- the current price in USD from CoinGecko
- threshold -- the target price threshold
- direction -- "above" or "below" -- which direction constitutes crossing
- crossed -- boolean indicating whether the price has crossed the threshold in the specified direction

Example response:

{ "asset": "bitcoin", "currentPrice": 102450.23, "threshold": 100000, "direction": "above", "crossed": true }

Not for: crypto prices only (use token_get_price), prediction market odds (use prediction_list_markets), stock prices (use stock_get_quote), trust/security scoring (use trust_score_evaluate).

Example agent prompts

- "Determine the outcome of a real-world event for prediction market settlement"
- "Quickly verify whether a factual claim is true or false"
- "Check if a cryptocurrency or stock price has crossed a specific threshold -- the most common resolution type in prediction markets"

Payment

- Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (eip155:8453)
- Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)

Part of klymax402

100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.

- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats

License

MIT