x discovery kit
x402 · machine-readable discovery

Your endpoint answers 402.
Crawlers still see nothing.

Agents and indexers look for six files before they trust an endpoint. If they 404, you are invisible no matter how good your service is. Fill the form once, get all six, valid and ready to serve.

163GET /openapi.json → 404
92GET /.well-known/x402 → 404
91GET /agents.json → 404
90GET /llms.txt → 404

Requests from automated agents to our four origins, measured over one day (2026-10-21). 436 misses that became files. Demand is real; the files were the gap.

Your endpoint

Nothing is uploaded. Generation runs in this page.

Generated files

Fill the form and press Generate.

—

Downloads are flattened (for example .well-known_x402). Rename each file to the path shown on its tab before serving it.

Where the files go

Serve each file at the exact path below on the same origin as the paid endpoint. Static files are enough: no backend, no dependency, no build step.

1. Drop them in the web root

Six small files. .well-known/x402 is a file, not a directory. Keep the JSON indentation; it is easier to diff.

2. Serve the dot-folder

Some servers hide /.well-known/. Add an exact location so it returns the file with application/json.

3. Check with curl

curl -i https://your-host/.well-known/x402 must return 200 and JSON. Repeat for the other five.

/openapi.json OpenAPI 3.1 + x-payment-info /.well-known/x402 x402 manifest: resources, price, network, payTo /agents.json agents-txt.com v1.0 /agents.txt plain-text companion /llms.txt llms.txt summary /robots.txt allow all, points at agents.txt

When the files are right and the listing still fails

Discovery files are necessary, not sufficient. The 402 challenge, the declared https resource, the Bazaar extension, the asset and the payTo must all agree. That diagnosis is a paid endpoint: listing-doctor ($0.05 per call, USDC on Base). Its own discovery files are generated by this same tool.