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agent402.tools api combinatorics
https://agent402.tools/api/combinatorics
payable
Compute combinations C(n, r) or permutations P(n, r) using BigInt for exact arbitrary-precision results. Returns the result as a string (since values can exceed Number.MAX_SAFE_INTEGER) and a human-readable formula.
We sent a real
POST request to this endpoint and it
answered 402 with payment requirements we could parse.
- Price
- $0.001
- Network
- base
- Pay to
- 0xaBF4FAbd7c416fB67202E5f9002389Fc75e2a9D0
- Spec dialect
- v2 (declares x402Version 2)
- Transport
- PAYMENT-REQUIRED header
- HTTP method
- POST
- Response latency
- 104 ms
- Payment options
- 12 usable of 12
- Last checked
- 2026-08-10T09:17:38.036Z (1d ago)
- Category
- mcp-server
Re-check it yourself:
curl "https://api.the402.dev/validate?url=https%3A%2F%2Fagent402.tools%2Fapi%2Fcombinatorics"