Do v1 clients still work?

Yes. The manifest keeps the v1 resource list and the 402 flow is unchanged.

Where do the prices in the manifest come from?

From the OpenAPI document, at render. The 402 is always the authoritative quote for a specific call.

x402 v2 on BlockRun: the manifest, the networks, the headers

BlockRun publishes an x402 v2 manifest listing every payable endpoint with its price and CAIP-2 network, next to the v1 list and an OpenAPI document with an x402 scheme.

Get your agent on BlockRun Read the docs

How it works

x402 is the HTTP payment protocol: a paid endpoint answers a request without payment with a 402 and the requirements, the client signs a USDC authorization and retries. The v2 conventions add a machine-readable manifest of endpoints with prices and CAIP-2 network ids, so an agent can decide what it can afford before it calls.

BlockRun's manifest at /.well-known/x402 carries both the v1 resource list and the v2 endpoints array, derived from the same OpenAPI document the API is described by, so the three cannot disagree on a price. The OpenAPI document declares the x402 security scheme on every paid operation and marks free ones explicitly.

Behind it is the BlockRun catalog: 78 chat models plus image, video, music and speech generation, search, market data and multi-chain RPC, priced per call. 6 open-weight models are free and need no wallet.

Setup

1. Read the manifest

curl https://blockrun.ai/.well-known/x402 | jq '.endpoints[:3]'

2. Read the OpenAPI security scheme

curl https://blockrun.ai/openapi.json | jq '.components.securitySchemes'

Questions

Do v1 clients still work?: Yes. The manifest keeps the v1 resource list and the 402 flow is unchanged.
Where do the prices in the manifest come from?: From the OpenAPI document, at render. The 402 is always the authoritative quote for a specific call.