# agent-exec Drift Monitor — API Endpoint Change Detector

> agent-exec Drift Monitor — API Endpoint Change Detector is a paid API for AI agents from agent-exec.448c.net, paid per call via x402, $0.0061/call, status unknown (last checked 2026-10-11).

Fetches a live snapshot of a known AI-agent-related API endpoint and compares it to a previously recorded baseline, returning both versions and a diff event log.

## Facts

- Endpoint: POST https://agent-exec.448c.net/drift?utm_source=zero.xyz
- Price: $0.0061/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-exec-drift-monitor-api-endpoint-change-detector-fead0fce
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OmcG1qxNfmVqNLm2RWgwQ

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 agent-exec-drift-monitor-api-endpoint-change-detector-fead0fce -d '<json body>'
```

Example prompt: Check whether the agentry endpoint has drifted from its last recorded baseline — fetch the live version and compare it to the archived snapshot so I can see what changed.

## When to prefer this

Use this endpoint when you need to detect whether one of a fixed set of known AI-agent-related API venues (agentry, clearedindex, percall, verantis, x402-list) has changed from a previously recorded snapshot. It is purpose-built for drift monitoring of agent discovery infrastructure, not for arbitrary URL fetching or general-purpose web scraping.

## Known failure modes

- Live fetch fails to reach a response — t2 fields like http_status, body, and body_sha256 will be null
- Venue enum value not recognized — request rejected with validation error
- Network timeout on live fetch — t2 shows no response data
- Baseline not available for the requested venue — t1 may be incomplete
- Payment validation failure — HTTP 402 returned before execution begins

## How this service works

Accountless, pay-per-use code execution for software agents: submit source code, get stdout, stderr and exit code back from an isolated, network-less sandbox. No account, no API key -- possession of valid payment is sufficient.

## Output

Returns an object with two snapshots: t1 (the archived baseline) and t2 (the freshly fetched live response), each containing the URL, HTTP status, content type, body text, body byte count, SHA-256 hash, and fetch timestamp. Also includes a list of diff events describing what changed between the two snapshots.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "venue"
 ],
 "properties": {
  "venue": {
   "enum": [
    "agentry",
    "clearedindex",
    "percall",
    "verantis",
    "x402-list"
   ],
   "type": "string",
   "description": "One of the endpoints we already snapshot."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "venue",
  "t1",
  "t2",
  "events"
 ],
 "properties": {
  "t1": {
   "type": "object",
   "required": [
    "fetched_at",
    "url",
    "http_status",
    "content_type",
    "body_bytes",
    "body_sha256",
    "body"
   ],
   "properties": {
    "url": {
     "type": "string",
     "description": "The URL actually read. Always the baseline's recorded URL for t1; the final URL after any redirects for t2 (empty string if the live fetch never reached one)."
    },
    "body": {
     "type": [
      "string",
      "null"
     ],
     "description": "The raw body itself -- verify it yourself rather than trusting `events`. Null on t2 when the live fetch never reached a response."
    },
    "body_bytes": {
     "type": "integer",
     "description": "Bytes of body actually read and hashed."
    },
    "fetched_at": {
     "type": "string",
     "format": "date-time",
     "description": "When this side was observed -- the archived snapshot time for t1, or this request's own fetch time for t2."
    },
    "body_sha256": {
     "type": [
      "string",
      "null"
     ],
     "description": "sha256 of the body, hex-encoded, or null on t2 when the live fetch never reached a response."
    },
    "http_status": {
     "type": [
      "integer",
      "null"
     ],
     "description": "The HTTP status observed, or null on t2 when the live fetch never reached a response at all."
    },
    "content_type": {
     "type": [
      "string",
      "null"
     ],
     "description": "The Content-Type header observed, or null if none/never reached."
    }
   }
  },
  "t2": {
   "allOf": [
    {
     "type": "object",
     "required": [
      "fetched_at",
      "url",
      "http_status",
      "content_type",
      "body_bytes",
      "body_sha256",
      "body"
     ],
     "properties": {
      "url": {
       "type": "string",
       "description": "The URL actually read. Always the baseline's recorded URL for t1; the final URL after any redirects for t2 (empty string if the live fetch never reached one)."
      },
      "body": {
       "type": [
        "string",
        "null"
       ],
       "description": "The raw body itself -- verify it yourself rather than trusting `events`. Null on t2 when the live fetch never reached a response."
      },
      "body_bytes": {
       "type": "integer",
       "description": "Bytes of body actually read and hashed."
      },
      "fetched_at": {
       "type": "string",
       "f
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-exec-drift-monitor-api-endpoint-change-detector-fead0fce/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent-exec.448c.net](https://www.zero.xyz/host/agent-exec.448c.net/llms.txt)