# x402-gateway changelog_openapi

> x402-gateway changelog_openapi is a paid API for AI agents from x402.freeq.one, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-13).

Generates a structured changelog from an OpenAPI specification, diffing versions to surface added, changed, or removed endpoints and schemas

## Facts

- Endpoint: POST https://x402.freeq.one/tools/changelog_openapi
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-gateway-changelog-openapi-9ce9fd9e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6TCVUQF3nTafaxf2cR-qD

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 x402-gateway-changelog-openapi-9ce9fd9e -d '<json body>'
```

Example prompt: Can you generate a changelog between my old and new OpenAPI specs? Here's the old spec URL: https://api.myapp.com/openapi-v1.json and the new one: https://api.myapp.com/openapi-v2.json — I want to see what endpoints were added, removed, or changed, especially any breaking changes.

## When to prefer this

Choose this endpoint when you need to automatically generate a changelog or detect breaking changes between two versions of an OpenAPI specification, especially in CI/CD pipelines or developer tooling workflows. It is ideal when you want a pay-per-call, no-subscription approach to API diffing without standing up your own diffing infrastructure.

## Known failure modes

- Invalid or unparseable OpenAPI spec returns an error
- Missing required spec input causes a 400-level error
- Network timeout if spec URLs are slow to fetch
- Specs with identical content return an empty or no-change changelog
- Malformed JSON/YAML in spec causes parse failure
- Payment not included or insufficient funds returns 402

## How this service works

Pay-per-call MCP gateway: 12 tools (markdown, token_price, wallet_portfolio, whale_alerts, cross_chain_balance, changelog_openapi, changelog_git, mermaid, html_to_markdown, qr_generator, og_image_generator, jobs). Per-tool prices on Base via the Coinbase CDP x402 facilitator: markdown=$0.001, token_price=$0.0005, wallet_portfolio=$0.002, whale_alerts=$0.002, cross_chain_balance=$0.002, changelog_openapi=$0.005, changelog_git=$0.005, mermaid=$0.005, html_to_markdown=$0.001, qr_generator=$0.001, og_image_generator=$0.001, jobs=$0.002. MCP flat rate $0.001.

## Output

A structured changelog derived from diffing two OpenAPI specifications, listing added, modified, and removed endpoints and schema changes, including breaking change indicators, formatted for developer consumption.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "new_spec": {
   "type": "object",
   "description": "New OpenAPI specification as a JSON object"
  },
  "base_spec_url": {
   "type": "string",
   "description": "URL of the base (old) OpenAPI spec"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-gateway-changelog-openapi-9ce9fd9e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.freeq.one](https://www.zero.xyz/host/x402.freeq.one/llms.txt)