58 services carry this tag in their source record. Tags come from the provider, not from us — a tag is a claim about what the service does, not proof that it does it well.
Canonicalize JSON before you hash, compare or sign it: one POST takes a JSON string or any JSON value and returns the RFC 8785 (JCS) form, its SHA-256 and its UTF-8 byte length. Object keys are ordered by UTF-16 code uni...
Signs a timestamped receipt for a file's sha256, proving it existed unchanged then. US$0.002 per call; POST the hash.
Compute keccak256/sha256, a 4-byte function selector, an event topic0, or an ENS namehash/labelhash from a string or hex input.
Did this page change, plus before and after sha256.
Fetch any page as clean markdown plus the sha256 of the extracted text.
Paid content hash + integrity ledger (cycle 217, x402 $0.01) - GET ?text=<STRING> OR ?data=<BASE64> OR ?sample=1|2|3 OR POST application/json {text|data}. Computes every digest an AI agent needs BEFORE it trusts a downlo...
Paid llms.txt multi-target drift monitor (cycle 149, x402 $0.001) - up to 20 domains in parallel via ThreadPoolExecutor; per_host H1 + first-5-URLs + sha256 fingerprint; compares to /tmp/llms_txt_monitor_state.json to de...
Paid CT-log certificate pre-fingerprint (cycle 124, x402 $0.001) - queries crt.sh for the target domain, parses every returned certificate record, and aggregates total_certs_observed + unique_sha256_count + duplicate_cer...
Paid SRI hash collision-risk + algorithm-strength probe (cycle 113) — parses every <script src integrity> and <link rel=stylesheet href integrity>, for each subresource: extracts the hash token (sha256/sha384/sha512/sha1...
Paid Subresource Integrity hash-match verifier — fetches every <script src=> + <link rel=stylesheet/modulepreload/preload href=> with integrity attribute, SHA-256/384/512-hashes the bytes and compares to declared base64...