# Kairostamp Evidence Snapshot

> Kairostamp Evidence Snapshot is a paid API for AI agents from kairostamp.com, paid per call via x402, $0.01/call, status down (last checked 2026-10-13).

Fetches a public URL server-side and returns a tamper-evident, time-stamped receipt with status, content type, byte length, SHA-256 hash, redirect chain, text preview, and hash-chain entry for evidentiary purposes.

## Facts

- Endpoint: POST https://kairostamp.com/api/v1/snapshot?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/kairostamp-evidence-snapshot-0805f05a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__MiwZsYZ2o9djzyI9htbD

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 kairostamp-evidence-snapshot-0805f05a -d '<json body>'
```

Example prompt: Take a tamper-evident Kairostamp snapshot of https://example.com/terms-of-service right now so I have a time-stamped, hash-verified receipt proving what the page said today.

## When to prefer this

Choose this endpoint when you need a cryptographically verifiable, tamper-evident record of a public URL's content at a specific point in time — especially for legal evidence, compliance auditing, or dispute resolution. It is distinct from a simple HTTP metadata check because it captures the full body hash and creates a hash-chain entry, and from a plain scrape because provenance and integrity are the primary outputs. Prefer this over the URL digest receipt sibling when you also need a text preview and the full redirect chain in addition to the hash.

## Known failure modes

- Non-public or private URLs return an access error or 4xx response recorded in the receipt
- URLs that require authentication or cookies cannot be fetched server-side
- Very large responses may be truncated in the preview portion
- Malformed or non-HTTP/HTTPS URLs are rejected with a validation error
- URLs behind bot-detection or CAPTCHA may return unexpected content or block the fetch
- Network timeouts for slow-responding servers may result in a fetch failure

## How this service works

Kairostamp evidence snapshot: server-side fetch of one public http/https URL, returning a time-stamped receipt with the response status, content type, byte length, SHA-256 of the body, redirect chain, a text preview, and a tamper-evident hash-chain entry.

## Output

A time-stamped receipt object containing: the fetched URL, HTTP response status code, content type header, body byte length, SHA-256 hash of the response body, the ordered redirect chain, a plain-text preview of the content, and a tamper-evident hash-chain entry that can be later verified via Kairostamp's receipt verification endpoint.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/kairostamp-evidence-snapshot-0805f05a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kairostamp.com](https://www.zero.xyz/host/kairostamp.com/llms.txt)