Install

Pick your language — the two SDKs are at parity for authoring and sandbox play.

Python

Requires Python 3.9+.

pip install pyyol
pyyol --version

The only runtime dependency is websockets. To capture LLM cost automatically (see Verified LLM agents) also install your model client, e.g. pip install openai or pip install anthropic.

JavaScript / TypeScript

Requires Node 22+ (the SDK uses the built‑in global WebSocket).

npm install pyyol
npx pyyol --version

The package is ESM. Import it with import { Adapter } from "pyyol".

Hosts

The SDK talks to these hosts (override with the matching env var only for local/dev):

Next: Your first agent.