# neo log-witness

> neo log-witness is a paid API for AI agents from neo-collettive.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-29).

Recomputes a hash-chained log's integrity, returning its size and head hash with a signed third-party witness attestation.

## Facts

- Endpoint: POST https://neo-collettive.onrender.com/x402/log-witness?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/neo-log-witness-0d4bf297
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hSMiAkW4dDhSCgBllgcMM

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability neo-log-witness-0d4bf297 -d '<json body>'
```

Example prompt: Can you recompute the integrity of my hash-chained log and get a signed third-party witness attestation? Here are up to 5000 entries in the format [seq, ts, kind, item, extra], and the starting head is 'abc123def456'.

## When to prefer this

Choose this endpoint when you need an independent, cryptographically-signed third-party attestation of a hash-chained log's integrity — not just local verification. Ideal when you need to prove to external parties that a log was intact at a specific moment, for audit trails, compliance checkpoints, or handoffs between systems. Prefer over self-signed solutions when external witness trust is required.

## Known failure modes

- Hash chain recomputation fails if entries are malformed or missing required [seq, ts, kind, item, extra] fields
- Exceeding 5000 entries limit returns an error
- Invalid or mismatched start_head causes chain verification failure
- Network timeout on large entry batches
- Malformed JSON input schema returns 400-level error
- Service unavailability on Render.com hosting platform

## How this service works

Recompute a hash-chained log ([seq, ts, kind, item, extra] rows, up to 5000) and get its size and head, signed and logged: a third-party witness line.

## Output

A JSON object with ok (boolean), the recomputed head hash of the log, the total log size (number of entries), and a cryptographic signature from neo acting as a third-party witness — serving as an externally-verifiable attestation of the log's integrity at that moment.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "log": {
   "type": "string"
  },
  "entries": {
   "type": "array",
   "maxItems": 5000
  },
  "start_head": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "head": "...",
  "size": 1,
  "signature": "..."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/neo-log-witness-0d4bf297/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from neo-collettive.onrender.com](https://www.zero.xyz/host/neo-collettive.onrender.com/llms.txt)