# x402pulse
> Independent observation of third-party x402 endpoints, and an anchored archive of what they did.
> Every tracked endpoint is probed every 10 minutes. Daily rollups are Merkle-rooted, chained to the
> previous day and submitted to OpenTimestamps calendars, which aggregate into Bitcoin. A submission
> returns a pending attestation — a promise, not a block — and each proof is upgraded to a Bitcoin
> attestation once the calendar has aggregated. /v1/archive/anchors publishes how many are attested
> and how many are still pending. No LLM inference anywhere: every response is a deterministic
> computation over recorded observations.
>
> Scope: this measures whether an endpoint answered, how fast, and whether its 402 offer was well formed.
> It does NOT establish that a seller is trustworthy, solvent, or that its data is correct. Endpoints
> operated by the same person who runs this observatory are tagged "self":1 in the archive rather than
> excluded, and continuity between anchored days is not established — the service redeploys.

## Start here: free evidence integration
- https://pulse.chainverdict.xyz/status.html — public operational status and disclosed record limitations; no wallet data
- GET /v1/status?url= — existing free probe now includes x401 envelope recognition; not credential validation or adoption evidence, not in the daily archive
- https://pulse.chainverdict.xyz/evidence.html — real dated refusal example, offline reference verifier, trust model and x401 scope
- https://pulse.chainverdict.xyz/inspector.html — free local x401 transport diagnostics and basic x402 offer checks; no credentials uploaded, no proof exchange or certification
- https://pulse.chainverdict.xyz/comparison.html — synthetic teaching scenarios, not a benchmark or verified production evidence
- /integration/summarize_observations.py — offline pinned-key summary adapter; no payment recommendation
- 56 damaged days (2026-08-07 through 2026-10-01), the 2026-10-02 transition and 2026-10-03 collector incident are excluded. First candidate full day: 2026-10-04, checkable after close on 2026-10-05 UTC and timestamp maturity.
- Pending timestamp proofs, missing days and stale evidence must not become a passing result.
- This is one operator, including self-observations. No paid-delivery or credential evidence is established.

## Paid endpoints (x402, USDC on Base)
- GET /v1/verdict?url= — live quality verdict for one x402 endpoint, $0.03
- GET /v1/rankings — measured ranking across tracked endpoints, $0.07
- GET /v1/attest?url= — Ed25519-signed attestation, 24h TTL, $0.12
- GET /v1/feed — bulk quality feed for routers and aggregators, $0.15
- GET /v1/archive/full — the whole anchored history in one response, $0.50

## Free
- GET /v1/datasets/manifest — what the archive holds, its cadence, and how to verify it yourself
- GET /v1/datasets/day/{day} — the most recent 7 days; JSON export containing exact canonical record strings
- GET /v1/archive/anchors — every daily Merkle root, its chain link and its OpenTimestamps proof
- GET /v1/selfcheck — this portfolio health, including what is currently broken
- GET /v1/methodology — what each measurement does and does not establish

## Machine-readable
- OpenAPI: /openapi.json
- Signing key (JWK set): /.well-known/signing-key.json
- Portfolio manifest: /.well-known/portfolio.json

## Verifying the archive without trusting this service
- sha256 each record line for a day, in the order served; Merkle them, promoting odd nodes rather than duplicating.
- That root must equal merkleRoot for the day in /v1/archive/anchors.
- sha256(prevChained || merkleRoot) must equal that day chained value.
- Verify chained against its OpenTimestamps proof with the standard `ots` client, independently of this service.