Pika API vs Runway API

Pika API

Keyless catalogue with live prices and JSON input schemas for 162 operations. $10 a month membership before any usage, and no free generation.

Runway API

OpenAPI 3.1, llms.txt and Markdown copies of every docs page. Gen-3 Alpha Turbo and Gen-4 Aleph were removed on 2026-07-30 with no prior notice in the changelog.

Pika API

1. Call GET /catalog/apis/{api_id}?expand=inputs first. It's free and returns the path, schema and price
2. Check GET /billing/balance before a submit. A 403 can mean an inactive key or an empty balance
3. Send an Idempotency-Key on every submit, and a fresh one only when you change the body
4. Record cost from billing.charge_micro_usd only once billing.state is settled

Runway API

1. Send X-Runway-Version: 2024-11-06 on every request or it fails
2. Use the SDK's wait-for-output helper or poll GET /v1/tasks/{id} until SUCCEEDED or FAILED
3. Don't retry a SAFETY.* failure unchanged. It's moderation, not an outage
4. Take model IDs from the models page, not memory. Two were removed without notice on 2026-07-30
5. Copy outputs to your own storage. URLs expire within 24 to 48 hours