Sandbox (test mode)

Test keys

Mint a test key in Settings → API by ticking "Test key (sandbox)". Test keys are prefixed fl_test_ and run the FULL request path - auth, rate limits, validation, moderation, idempotency, webhooks - but every render is simulated:

• no provider calls and no credits consumed;
• the job completes immediately with a sample video URL;
• if you set webhookUrl, you receive a real, correctly-signed completion webhook so your receiver verifies the exact payload/signature shape a live job sends.

Build and exercise your polling/webhook flow end-to-end for free, then swap in a live fl_ key.

Response marker

Sandbox generations return sandbox: true:

{ "jobId": "…", "status": "completed", "sandbox": true }

The job appears in GET /api/v1/status/{jobId} and GET /api/v1/videos with renderStatus: "done" and a sample finalVideoUrl - exactly the shapes a real finished render produces, so your happy-path code runs unchanged.

Limits

• Sandbox jobs are records, not renders: you can't publish or edit them.
• The fail-safe direction is toward simulation: a key minted with the fl_test_ prefix is always treated as a test key, even if its database flag is missing.