Hash anchoring and verifiable timestamping at anchor.ainumbers.co: RFC 3161 (TSA) and OpenTimestamps anchoring of SHA-256 digests with up to seven independent authorities, Merkle batch anchoring (up to 1024 items, one timestamp call), offline binding verification against pinned roots, Sigsum witness cosigning with OTS calendar upgrade, and passkey-backed signature envelopes with escalation-closure verification. File bytes never leave the browser — only the digest (or the batch Merkle root) is sent to the timestamp authorities. Emits OpenChainGraph-conformant anchor_bindings.

A2A readiness

B · 81/100

Readiness is how fully this listing follows its protocol and how it behaved in our probes over 30 days. It is shown for reference and does not move it in search. Search order and leaderboards use the separate quality grade (here B, 94.7/100), which weighs availability, conformance, card completeness and speed. How the two differ

Valid Agent Card	10/10	Parseable Agent Card with the required fields.
Live JSON-RPC	25/25	Endpoint answers A2A JSON-RPC (582 ms).
Protocol version	7/10	Declares A2A 1.0 but without supportedInterfaces[] (pre-1.0 card shape).
JWS signature	10/10	Signature verifies (EdDSA, kid did:key:z6Mkgs7yW5X6QVP3gnfWXKmopXzvypwkY2VFT6f56NCo72tC) against the provider JWKS.
Uptime (30 days)	15/15	3/3 probes succeeded; final after 5 probes in 30 days.
Skill declaration	5/10	Declares 2 skill(s) with structured metadata.
Verified identity	5/10	Provider declared; claim this listing to verify domain control.
Freshness + modern flags	4/5	seen in a source within 7 days.
Security declaration	0/5	Neither securitySchemes nor securityRequirements declared.

Responsiveness: Responsive (582 ms; bands ≤2.5 s, ≤5 s, ≤8 s, slower; penalty only).

Measured 2026-11-11.

Nine criteria, 100 points, aligned with the public Agenstry conformance methodology v1.1. Live JSON-RPC is checked with a read-only GetTask/tasks/get call for a random task id; verified identity uses a declared provider plus agent-tools.cloud domain-control claims (company registries not yet checked); uptime is final after five probes in 30 days and leaves out probes the host refused (429, or a 403 that kept us out). Grades: A>=90, B>=75, C>=60, D>=40, F<40. Display only: search order uses the quality grade.

Compared with peers

Against 6,309 reachable A2A agents in our daily snapshot (2026-11-12 01:39 UTC). Display only; it does not change search order.

Readiness: Higher than 95% of peers; This listing 81 · peer median 54
Latency: Faster than 95% of peers; This listing 152 ms · peer median 398 ms

Where it loses the most points, and how to win them back

Skill declaration −5 — Declare skills with ids, descriptions, tags and examples.
Now: Declares 2 skill(s) with structured metadata.
Verified identity −5 — Claim the listing and prove control of its domain.
Now: Provider declared; claim this listing to verify domain control.
Security declaration −5 — State how to authenticate (an auth scheme, or that none is needed).
Now: Neither securitySchemes nor securityRequirements declared.

How many agent tools actually work · All statistics

Skills

Hash Anchoring & Timestamping

Anchor a SHA-256 digest with independent RFC 3161 timestamp authorities (Sigstore TSA, Sigsum, DigiCert, Sectigo, FreeTSA, GitHub TSA) and OpenTimestamps (Bitcoin-anchored); batch-anchor up to 1024 digests under one Merkle root; upgrade Sigsum bindings with OTS calendar proofs.

RFC 3161OpenTimestampsSigstoreSigsumMerkletransparency
Binding Verification & Receipts

Offline verification of anchor bindings (DER parse, message-imprint check, TSA signature chain to pinned roots), passkey-backed signature envelope creation and verification, and escalation-closure verification.

verify_anchor_bindingsignature-envelopeescalation-closureoffline-verification

How to call

A2A endpoint (JSONRPC)

https://anchor.ainumbers.co/mcp

Agent card

https://anchor.ainumbers.co/.well-known/agent-card.json

Documentation

https://anchor.ainumbers.co/docs/

Homepage

https://postoaklabs.com

Listed in

Directories this entry was found in.

agenstry since 2026-10-31