# GET /openapi: $0.005 per call

Understand any public API fast: give its OpenAPI/Swagger spec URL, its docs or base URL, or a name from the APIs.guru directory (?api=stripe.com); we find the spec and return title, version, servers, auth schemes, tags and every operation (method, path, summary, parameters, body, responses), filterable by tag or search. ?api=stripe.com&q=customer

- **Price:** $0.005 in USDC, the same on Base, Solana, Polygon, Arbitrum. Failed calls are never charged.
- **Free trial:** yes, 20 free calls a day from Claude, Cursor or any MCP client ([set-up](/mcp/setup)).
- **Tier:** live
- **Answers cached for:** 6 hour(s)
- **Data sources:** The API's own OpenAPI/Swagger spec (free); APIs.guru directory (free)
- **Lane:** AI coding agents ([OpenAPI](/openapi/coding.json))
- **Live health:** [status page](/status)

## Free sample

See an answer for the demo input first, free (no payment, 10 a minute): [https://aayatai.com/sample/openapi](/sample/openapi). It is a stored real answer when we have one, otherwise an example marked `"kind": "illustrative"`.

```bash
curl "https://aayatai.com/sample/openapi"
```

## 1. See the price (free)

Call it without paying: you get `402 Payment Required` and a `PAYMENT-REQUIRED` header with the exact price and where to pay.

```bash
curl -i "https://aayatai.com/openapi?api=stripe.com&q=customers&limit=50"
```

## 2. Pay and call (TypeScript)

```bash
npm install @x402/fetch @x402/evm viem
```

```ts
import { wrapFetchWithPaymentFromConfig } from "@x402/fetch";
import { ExactEvmScheme } from "@x402/evm";
import { privateKeyToAccount } from "viem/accounts";

// A wallet used only by your agent, holding a little USDC on Base.
const account = privateKeyToAccount(process.env.WALLET_PRIVATE_KEY as `0x${string}`);
const pay = wrapFetchWithPaymentFromConfig(fetch, {
  schemes: [{ network: "eip155:8453", client: new ExactEvmScheme(account) }],
});

const res = await pay("https://aayatai.com/openapi?api=stripe.com&q=customers&limit=50");
console.log(await res.json());
```

## 3. Or as an MCP tool

```ts
// MCP server: https://aayatai.com/mcp (Streamable HTTP). With the x402 MCP client (see /start):
const result = await client.callTool("openapi", {"api":"stripe.com","q":"customers","limit":50});
```

## Inputs

- `url` (string): Spec URL (JSON), or the API's docs/base address to look for a spec at common paths.
- `api` (string): Or: an APIs.guru name, e.g. stripe.com, twilio.com:api, github.com:api.github.com.
- `tag` (string): Only operations with this tag.
- `q` (string): Only operations whose path, summary or operationId contains this text.
- `limit` (integer; default `200`): Most operations to list.

Bad inputs are rejected with HTTP 400 before any payment is asked for.

## Example answer

```json
{
  "source": {
    "url": "https://api.apis.guru/v2/specs/stripe.com/2022-11-15/openapi.json",
    "via": "apis.guru",
    "key": "stripe.com"
  },
  "title": "Stripe API",
  "version": "2022-11-15",
  "specVersion": "3.0.0",
  "description": "The Stripe REST API.",
  "servers": [
    "https://api.stripe.com/"
  ],
  "auth": [
    {
      "name": "bearerAuth",
      "type": "http",
      "scheme": "bearer",
      "in": null,
      "header": null,
      "flows": []
    }
  ],
  "tags": [],
  "totals": {
    "operations": 540,
    "paths": 400,
    "schemas": 900,
    "deprecated": 12
  },
  "operations": [
    {
      "method": "POST",
      "path": "/v1/customers",
      "operationId": "PostCustomers",
      "summary": "Creates a new customer object.",
      "tags": [],
      "parameters": [],
      "body": {
        "required": false,
        "contentTypes": [
          "application/x-www-form-urlencoded"
        ]
      },
      "responses": [
        "200",
        "default"
      ],
      "deprecated": false,
      "auth": null
    }
  ],
  "matched": 20,
  "truncated": false,
  "fetchedAt": "2026-09-28T12:00:00.000Z"
}
```

## Related

- [GET /docs/find](/services/docs-find) ($0.003): Find the AI-ready docs for any library or API: checks the project's docs site (from its npm, PyPI, crates or Go metadata) or any company domain (docs., develope
- [GET /docs/lib](/services/docs-lib) ($0.005): Up-to-date docs for any npm, PyPI, crates or Go library, trimmed for a coding agent's context: finds the project's own llms.txt and docs pages (or the latest re
- [POST /docs/answer](/services/docs-answer) ($0.02): Ask a coding question about any npm, PyPI, crates or Go library and get an answer written only from its current docs (project llms.txt, docs pages or latest REA
- [GET /library/research](/services/library-research) ($0.10): Premium research report on a library or API for coding agents: reads its current docs for your goal, checks version, safety and repository health, gathers what 
- [GET /package/check](/services/package-check) ($0.005): Should a coding agent install this package?
- [GET /dependency/verdict](/services/dependency-verdict) ($0.03): "Should I use this dependency?" in one call for npm, PyPI, crates or Go: full package safety check (vulnerabilities, malware, typosquats, deprecation, licence, 
- [GET /dependency/report](/services/dependency-report) ($0.08): Premium "should I use this dependency?" report: package safety (vulnerabilities, malware, typosquats, deprecation), GitHub repository health, licence compatibil
- [GET /package/changes](/services/package-changes) ($0.005): What changed between two versions of an npm, PyPI, crates or Go package: every release's notes from GitHub releases (or the CHANGELOG), newest first, with lines

New here? [Getting started in 60 seconds](/start). All services: [Aayat AI](/).