site-to-api

Record one browsing session of a website. Get the OpenAPI specs, request flows and typed client a coding agent needs to build a wrapper for its internal API.

For developers who need to integrate with a website that has no public API. Use it only on sites you are allowed to use; it never bypasses bot protection, captchas or access controls.

site-to-api records what a site's own pages do while you use it (or reads a HAR you exported), then works out the endpoints, their parameters and schemas, the order requests happen in, which value feeds which request, and what a session needs. No LLM runs inside it. It writes one handoff folder with:

• OpenAPI 3.1 specs, plus AsyncAPI 3.0 for WebSocket and event-stream channels;
• request flows with the origin of every input;
• readable maps for an agent (AGENT.md, one file per host);
• excerpts of the site's own source code;
• a typed TypeScript client with Zod validation, and optionally an MCP server.

Raw captures stay in a gitignored folder. Everything in the handoff folder is redacted by default.

Install

Requires Node 22.12 or later.

npm install -D site-to-api              # the CLI
npm install site-to-api-runtime zod    # what the generated client imports

capture opens Google Chrome, or Playwright's bundled Chromium where Chrome is not installed; download that once with npx playwright install chromium. With pnpm, which does not expose Playwright's command, add playwright at the version site-to-api depends on before running pnpm exec playwright install chromium.

Use

npx site-to-api init                          # writes site-to-api.config.ts
npx site-to-api capture https://example.com   # use the site, close the browser to finish
npx site-to-api build                         # writes api-handoff/: specs, flows, AGENT.md, client
npx site-to-api probe                         # optional: what plain HTTP needs, rate limited

Already have a HAR? npx site-to-api import session.har --delete-source, then build.

Then point your coding agent at api-handoff/AGENT.md, or serve the folder to it over MCP with npx site-to-api mcp ./api-handoff. gen.clientDir in the config puts the client in your app's source tree.

For an agent that runs the CLI itself, the package ships its skill (commands, rules, workflow) at node_modules/site-to-api/skills/site-to-api/SKILL.md; npx site-to-api init --agent copies it into .claude/skills/ and .agents/skills/ and points the project's AGENTS.md or CLAUDE.md at it.

Documentation

The repository holds the full documentation:

• README: capture, HAR import, the client in an app, MCP, known limits;
• using the client;
• configuration;
• output format;
• changelog;
• responsible use: build integrations only with sites you are allowed to use, and never against bot protection, rate limits or access controls.

MIT licence.