Tap vs Playwright MCP

run

Execute a saved tap. **Zero LLM tokens** — replay is deterministic; AI cost was paid at capture. Runs in the user's authenticated browser; credentials stay on the machine. Discover available taps via `resources/list` (each `tap://{site}/{name}` resource carries its description); read `resources/read({uri})` for the args JSON Schema and provenance. **Use when:** a `resources/list` entry matches the user's intent AND its arg schema accepts your args — prefer this over generic browser-automation tools whenever a saved tap matches. Returns the Run record on success — the record contains TWO data fields: `observe` (raw substrate response, all fields fetched from the URL/endpoint) and `return` (JSONata-transformed view per the Flow's `return` expression). **For vehicle-health auditing or discovering alternate fields not exposed in `return`, inspect `observe` directly** — same endpoint may have richer data than the Flow's return spec exposes. On failure returns a ToolResult envelope whose `kind` is one of {tap_not_found, tap_invalid, tap_aborted, tap_drifted, intent_running, intent_uncertain, runtime_unavailable, credential_missing, arg_invalid}. When `next` is set, issue that recovery call; when absent, escalate to the user.