# Changelog State API – Clerk Vendor Change History

> Changelog State API – Clerk Vendor Change History is a paid API for AI agents from changelog-state-api.replit.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Returns detected changelog update history for the Clerk vendor, including new releases, version changes, date changes, title changes, and breaking signals.

## Facts

- Endpoint: GET https://changelog-state-api.replit.app/api/monitors/clerk/changes
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/changelog-state-api-clerk-vendor-change-history-af7fe07d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OQLZvEnjChMP61iA-N_8s

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 changelog-state-api-clerk-vendor-change-history-af7fe07d
```

Example prompt: Pull the Clerk changelog change history and show me any breaking signals or new releases detected in the last 30 days, up to 100 results.

## When to prefer this

Choose this endpoint when you need historical changelog change events for the Clerk vendor specifically, especially when you want to filter by change type (e.g. only breaking signals or new releases) or query changes after a specific timestamp. Prefer this over general release endpoints when you need the raw detected-change audit trail rather than structured release summaries.

## Known failure modes

- Invalid or unknown vendor slug returns 404 or empty result set
- Malformed 'since' datetime format causes a 400 validation error
- Limit out of range (below 1 or above 200) causes a 400 validation error
- Payment not included or rejected causes a 402 Payment Required response
- Upstream changelog source unavailable results in stale or empty data
- Unknown change type enum value in query causes a 400 validation error

## How this service works

Detected changelog update history for one tracked vendor.

## Output

A JSON array of detected changelog change records for the Clerk vendor, each entry including the change type (e.g. new_release, version_changed, date_changed, title_changed, breaking_signal), the detection timestamp, and relevant metadata about what changed in Clerk's changelog.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "slug"
     ],
     "properties": {
      "slug": {
       "type": "string",
       "pattern": "^[a-z0-9][a-z0-9-]*$",
       "maxLength": 64,
       "minLength": 1,
       "description": "Vendor slug, lowercase alphanumeric with dashes."
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "type": {
       "enum": [
        "new_release",
        "version_changed",
        "date_changed",
        "title_changed",
        "breaking_signal"
       ],
       "type": "string",
       "description": "Restrict to a single change type."
      },
      "limit": {
       "type": "integer",
       "default": 50,
       "maximum": 200,
       "minimum": 1,
       "description": "Maximum number of change rows to return."
      },
      "since": {
       "type": "string",
       "format": "date-time",
       "description": "Only return changes detected at or after this instant."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "enum": [
      "json"
     ],
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   },
   "description": "Detected changelog update history (paid)"
  }
 },
 "description": "Call shape for GET /api/monitors/{slug}/changes."
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/changelog-state-api-clerk-vendor-change-history-af7fe07d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from changelog-state-api.replit.app](https://www.zero.xyz/host/changelog-state-api.replit.app/llms.txt)