Web search

A built-in, Tavily-backed search tool. Declare it in agent.yaml, set TAVILY_API_KEY, and your agents search the live web with no handler to write:

name: researcher
model: anthropic/claude-sonnet-5
builtin_tools: [web_search]

That is the whole setup. The loader folds TAVILY_API_KEY into the agent's required env, so a missing key fails fast at startup with a clear message instead of dying mid-run. Locally the key comes from your environment or .env; on AWS, deploy-aws reads TAVILY_API_KEY and stores it in Secrets Manager like the model keys.

The agent sees a web_search tool taking {query, max_results} and gets back JSON: a short answer when Tavily can produce one, plus the top results as {title, url, snippet}.

Durability

Searches are recorded in the event log with keyed idempotency, like every tool call. A crashed and resumed run replays the recorded results instead of re-searching: no double spend on your Tavily quota, and the agent reasons over the same facts before and after a resume, so replay verification holds.

Bring your own instead

web_search is a convenience, not a lock-in. A different provider is a normal defineTool() in your agent's tools/ directory; if you name it web_search while the builtin is declared, the loader refuses at startup rather than letting two tools collide.

Get a key at tavily.com; the free tier is plenty for development.