# Changelog State API – Chrome Change History

> Changelog State API – Chrome 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 (new releases, version changes, date/title changes, breaking signals) for the Chrome vendor tracked by the monitoring service.

## Facts

- Endpoint: GET https://changelog-state-api.replit.app/api/monitors/chrome/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-chrome-change-history-a8382987
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_q_p2Sr9JkWhmStJOquWav

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-chrome-change-history-a8382987
```

Example prompt: Can you pull up the changelog change history for Chrome from the Changelog State API — show me all changes detected in the last 7 days, up to 50 results?

## When to prefer this

Use this endpoint when you need historical change detection records for Chrome specifically — including granular change types like breaking signals or title changes — rather than just structured release notes. Prefer this over the releases endpoint when you want raw change events with detection timestamps rather than curated release summaries. Ideal for automated monitoring pipelines, CI triggers, or audit trails.

## Known failure modes

- 404 if slug is unrecognized or the literal placeholder '{slug}' is used instead of a real vendor name
- 400 if query parameters are malformed (e.g. invalid date-time format for 'since', limit out of 1–200 range)
- 402 Payment Required if x402 micropayment header is missing or insufficient
- Empty array if no changes match the given filters (not an error, but may indicate no activity in the window)
- 500 if the upstream changelog monitor is unavailable

## How this service works

Detected changelog update history for one tracked vendor.

## Output

A JSON array of detected changelog change records for Chrome, each containing the change type (new_release, version_changed, date_changed, title_changed, or breaking_signal), detection timestamp, and associated metadata such as version strings or title diffs. Results are paginated up to the requested limit.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "slug"
     ],
     "properties": {
      "slug": {
       "type": "string",
       "example": "openai",
       "pattern": "^[a-z0-9][a-z0-9-]*$",
       "maxLength": 64,
       "minLength": 1,
       "description": "Vendor slug, lowercase alphanumeric with dashes. Take one from GET /api/monitors and substitute it into the path: `{slug}` is a placeholder, and requesting those literal characters returns 404. Worked example: GET /api/monitors/openai."
      }
     }
    },
    "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-chrome-change-history-a8382987/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)