Function selector / event topic
Resolve a 4-byte function selector or a 32-byte event topic hash to its known human-readable Solidity signatures, via the openchain.xyz signature database with 4byte.directory as fallback. Unknown selectors return {found:false} with an empt
Go to this service →Our latest check (2026-10-11)
- Answering
- Yes — valid x402 payment terms
- Time to answer
- 194 ms
- Price
- $0.002 per call
- Paying buyers, last 30 days
- 4 (directory's own records)
- Paid calls, last 30 days
- 6
- Category
- Events, tickets and sports
- Address
- https://agent402.tools/api/selector-lookup
Accuracy
Accuracy scores are published once a seller has enough paid checks against an independent record (at least 7 scored answers over at least 7 days). Until then no score is shown, and a missing score is never a pass.
For agents
This page as JSON: /sellers/f900c92c6200.json. Paid lookup by address: GET /api/seller?resource=… ($0.001, x402).