Link Preview Cache API

tools

A portfolio of small, single-purpose paid services sold directly to AI agents — no human checkout flow, no dashboard login, no subscription. An agent calls the API, gets an HTTP 402 Payment Required quote, pays a few cents in USDC, and gets its answer. Fully automatic on both sides.

Each service lives in its own self-contained folder under projects/ and follows the same pattern:

• One narrow problem, solved well. No platforms, no suites — a single job an agent needs done.
• x402 for payment. HTTP-native, stablecoin micropayments, no merchant account or KYC required on the seller side — just a wallet address. This is the emerging standard for agent-to-API payments (backed by Coinbase, adopted by AWS Bedrock AgentCore, Cloudflare, and others as of 2026).
• Discoverable by agents, not just humans — each API declares an x402 Bazaar discovery schema so agents can find and call it without a human ever reading the docs.
• A sample automation client included with every project, showing an agent discovering, paying for, and consuming the service end-to-end.
• Where it adds real reach, also sold as an MCP tool (api/app/mcp_server.py) — the same product, the same price, a second interface for coding agents that discover tools over MCP rather than raw HTTP.

Projects

Project	What it sells	Status
link-preview-api	Pay-per-call URL metadata (Open Graph/title/description/image) extraction	Live on Base mainnet, earning real USDC: https://link-preview-api-z4nf.onrender.com
content-moderation-api	Pay-per-call profanity/explicit-content detection with redaction, sold over both HTTP and MCP	Live on Base mainnet, earning real USDC: https://content-moderation-api-hhy1.onrender.com
link-preview-cache-api	Same product as link-preview-api, ~⅓ the price — backed by a shared cache. First instance of a general "x402 cache" pattern	Live on Base mainnet, earning real USDC: https://link-preview-cache-api.onrender.com

Repo conventions

• Every project is fully self-contained in projects/<project-slug>/: its own code, tests, Dockerfile, deploy config, and README. Nothing product-specific is shared between projects.
• Every project ships with:
  • api/ — the paid service itself
  • automation-client/ — a sample agent that pays for and consumes it
  • deploy/ — ready-to-use deploy configs (Render/Fly/etc.)
  • README.md — the business case, architecture, and exact steps to take it from "runs on my machine" to "earning money"
  • LISTING.md — the marketplace/directory listing copy, ready to publish
• New projects get added the same way: a clean new folder, same skeleton, linked in the table above.
• One deliberate exception to "nothing shared": scripts/ holds portfolio-level publishing tooling — not product code, reused across every project the same way (e.g. submitting a new tool to x402-list.com's API). See PUBLISHING.md for the full playbook: what's genuinely automatic, what's scripted, and what stays a deliberate manual step and why.