# Prompt402

> Pay-per-request Higgsfield video API with Seedance 2.5 text-to-video, x402 payments and live upstream pricing plus a fixed 10% markup. No subscription.

Prompt402 is independent and is not affiliated with Higgsfield or ByteDance. It accepts an explicit allowlist of text-to-video operations, not arbitrary model slugs.

## Documentation
- [API guide](https://prompt402.com/docs): quote, x402 payment, retries, polling and failures.
- [Pricing](https://prompt402.com/pricing): live upstream estimate plus a fixed 10% service markup, rounded up to micro-USDC; no subscription.
- [Seedance 2.5](https://prompt402.com/models/seedance-2.5): supported text-to-video settings and official upstream mode sources.

## Machine-readable discovery
- [OpenAPI](https://prompt402.com/openapi.json): authoritative model-specific input schemas.
- [x402 discovery](https://prompt402.com/.well-known/x402): x402 v2 exact payment resource.
- [Storefront](https://prompt402.com/api/storefront): API and payment behavior.
- [Pricing JSON](https://prompt402.com/pricing.json): pricing policy, not a live quote.
- [Pricing Markdown](https://prompt402.com/pricing.md): human and agent-readable policy.
- [Consolidated guide](https://prompt402.com/llms-full.txt): request guide, model scope, pricing and FAQs.

## Request lifecycle
POST /api/v1/quote accepts the same generation body without payment or submission.
POST /api/v1/generations requires an 8–255 character Idempotency-Key. Inspect the 402 challenge and retry the same request with PAYMENT-SIGNATURE using an x402 client.
Payment settles upfront; rejected submissions require refund review, not an automatic refund. Completed submission replays return the original job without another charge.
GET /api/v1/generations/{id} polls only IDs submitted and recorded by this service. Poll no more than once every two seconds.
Production uses Base mainnet USDC; development and previews use Base Sepolia test USDC. The challenge specifies the active network and payable amount.

## Model scope
Supported: bytedance/seedance-2.0/text-to-video, bytedance/seedance-2.5/text-to-video.
Seedance 2.5 image-to-video, reference-to-video, video-edit and video-extend are not supported by Prompt402.
Official model sources last verified: 2026-09-17. Integration checks are hermetic, not real generation or payment tests.