Stagehand Act Extract Observe

Stagehand init with env=BROWSERBASE. Agent calls await stagehand.page.act('click the Sign in button').

act() resolves a single high-level action against the live DOM via the model. Verify the resulting action via a post-click anchor (URL change, observe() result, or DOM presence of a known signed-in element). Do not chain multiple imperative steps in one act() string.

Agent extracts product details: await stagehand.page.extract({instruction:'price and title', schema:z.object({price:z.string(), title:z.string()})}).

Pass a strict Zod schema so the model returns typed JSON. Validate the result at the boundary and route schema-violation back as a retry signal. Persist raw model output alongside the typed object for audit when downstream uses it for decisions.

observe() returns a candidate selector for 'the buy button'. The agent reuses it 30 seconds later after a partial DOM update.

observe() selectors are tied to the snapshot at observation time. Re-observe before reuse on dynamic SPAs. If reuse is needed for speed, validate with a presence check and fall back to a fresh observe() on miss.