Yam documentation
Yam is a deterministic automation runtime with a standard agent surface, from Svatah Labs. Describe a behaviour once in plain language, bind it to the real elements by driving the real platform, then replay that plan deterministically, with no model in the loop. The support matrix says which platforms that covers and how far each has been driven; it is generated from measured runs rather than written.
The documentation is organised by what you are trying to do.
| If you want to | Read |
|---|---|
| connect an AI agent to Yam | Yam MCP |
| install it and run something | Setup |
| see everything Yam does | Features |
| learn from working examples | Examples |
| look up a command, tool or endpoint | API reference |
| get bindings into an existing Playwright suite | Playwright quick start |
| do one specific task | Guides |
| understand how and why it works | Concepts |
| work on Yam itself | Developer guide |
| send a change | Contributing |
Start here
- Setup, from
npm installto a working machine, including the permissions macOS wants and which program it grants them to. - Features, what Yam does, one feature at a time, with pictures.
- Examples, working code for the things people do most.
Getting started, in detail
- Install Yam and control something, from
npm installto a browser and a native application driven by hand, then by an agent through Yam MCP. - Bindings in a plain Playwright project, the smaller thing to adopt if you already have a Playwright suite.
- Your first flow, from
yam initto a replayed plan. - One plan, three ways to run it, as a test, a workflow and an agent tool.
Guides
- Record bindings
- Heal bindings when the interface changes
- Write a flow
- Run in CI
- Run a story from cron
- Expose a story as an MCP tool
- Add an adapter and pass conformance
- Write a foreign runtime
- Use the desktop app
Concepts
- Yam MCP, how an agent drives Yam, and how its session becomes a test
- The three layers
- The agent surface
- Determinism and provenance
- Bindings and fingerprints
- The compiler tiers
- Behaviors
- Privacy mode
Reference
Written by hand:
- API reference, the four ways in and which to pick
- The flow language, every sentence pattern and IR action
- The agent surface contract, what an adapter implements
- MCP, the operation tools and the raw surface
- The REPL
- The local model, Tier 2 and the fine-tune
Generated from the code by pnpm docs:build, and checked in CI so they cannot drift:
- Support matrix, which adapters have been driven and how far
- The
yamcommand line - Packages and their exports
- JSON Schemas
- The local service HTTP API
Project
- Surface-first mission proposal, with Yam-on-Yam gap analysis, requirements, design and implementation tasks
- Changelog · Versioning
- Reports, the published numbers and how to regenerate them
- Continuous integration
- Contributing · Developer guide · Security
- The specification, the source of truth: requirements, HLD, LLD, tasks, and every phase's record and verification