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	$0.012	Resolve a prediction market event/question. Aggregates multiple data sources to determine outcome with confidence score.
event_verify_claim	POST	/api/verify	$0.008	Quick-verify a factual claim. Returns verdict (true/false/unverifiable) with confidence and evidence.
event_check_price_threshold	POST	/api/price-check	$0.005	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