API sandbox · zero credentials

Make the first request before you have an account.

Run every normalized API contract against deterministic source-backed fixtures. Learn response handling, empty states, authentication failures, throttling, and recovery—then replace the fixture with an entitled trusted-server call.

Choose an API Inspect machine catalog

162API contracts

Every normalized operation has the same sandbox runner.

7API families

Product generations and evidence remain distinct.

6deterministic scenarios

Success, empty, validation, auth, quota, and availability.

0provider calls

No token, key, entitlement, or external request is accepted.

From zero to production

A truthful rehearsal, not a pretend live API.

The request identity, response, status, and simulated latency are deterministic. The sandbox cannot prove account access, regional behavior, live data, quota, performance, provider availability, or version compatibility.

01
Compose
Edit the source-backed request on any API reference page.
02
Exercise
Run all six fixtures and implement explicit UI and retry behavior.
03
Integrate
Move generated code into a trusted runtime with an approved credential.
04
Conform
Run bounded non-production live verification and retain provider evidence.

Fixture contract

{
  "schemaVersion": "mappls.api-sandbox.v1",
  "fixture": true,
  "liveProviderCall": false,
  "response": {
    "status": 200,
    "headers": {
      "x-mappls-fixture": "true"
    },
    "body": "source example or explicit fixture boundary"
  },
  "provenance": {
    "authority": "source-contract-example",
    "boundary": "not production evidence"
  }
}

Failure-aware by default

Ship the uncomfortable paths first.

A sandbox session is complete only after the application handles every expected status deliberately.

Success

Return captured source-contract examples; when none exists, show declared field evidence without inventing a provider payload.

Empty

Exercise an explicit no-content path so zero-result handling is never postponed until production.

Validation

Return a bounded 400 fixture for invalid request and form-recovery testing.

Authentication

Prove 401 handling without accepting or manufacturing a credential.

Rate limit

Return retryable 429 evidence plus a deterministic Retry-After boundary.

Unavailable

Exercise bounded 503 recovery, backoff, and user-facing degradation.

Start anywhere

Every operation is executable now.

Open a contract, edit the request, and run the embedded sandbox. The same inputs generate cURL, JavaScript, Python, Java, C#, Go, PHP, and Ruby.

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