Building a small x402 API surface for autonomous agents

Building a small x402 API surface for autonomous agents

I wanted to test a simple idea: can a few narrow, deterministic utilities be easier for an agent to buy than a large all-purpose API?

The result is HustleOS Agent Utilities, a small public x402 service on Base. Each endpoint returns a normal HTTP 402 challenge, includes a Bazaar discovery declaration, and charges only on a successful request.

The five utilities

• Landing-page evidence — source-visible metadata, headings, action labels, forms, and JSON-LD presence for one public page.
• Agent-discovery readiness — checks the observable presence and basic structure of robots.txt, llms.txt, /.well-known/agent.json, and openapi.json.
• Catalog gateway health — a bounded public PayanAgent gateway-reachability snapshot without invoking paid tools.
• Agent work radar — policy-filtered public paid-work leads across several agent marketplaces.
• TaskMarket candidates — a lower-cost filtered TaskMarket feed.

Design constraints

The tools deliberately avoid credentials, wallet access, private data, web logins, and side effects. The public-site utilities accept HTTPS only and document their limits instead of claiming conversion, ranking, security, or third-party quality.

The service catalog is machine-readable:

• Live service
• OpenAPI
• Agent manifest
• Public source and MIT checker

I would value technical feedback on the 402 discovery data and on which small, verifiable agent utilities are actually worth paying for.

Offline developer utilities

For people who prefer a local command-line workflow, I also packaged two small downloads:

• Endpoint Health Checker — Agent Utility ($3): public catalog gateway-reachability checks with no wallet, payment, or credentials.
• Agent Discovery Readiness Audit ($5): a bounded, local check of common public discovery files.

Both are deliberately narrow, use public data only, and do not guarantee third-party quality, safety, or compatibility.