browser_login

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does so: it discloses that credential values are redacted in every result and masked in screenshots, that submit=false only fills and does not press the button, and that a `page` snapshot is returned on submission/navigation/auth change.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Dense but front-loaded: the core action and its prerequisite come first, with the redaction/snapshot/fallback details following. Slightly long, but essentially every clause adds operational information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema exists, and the description compensates by explaining what the result contains (redacted values, optional `page` snapshot). For a 3-parameter auth tool with no annotations, nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% so each parameter is already documented, but the description adds real meaning: account_hint disambiguates among multiple saved accounts for a site, submit triggers the sign-in button press, and tab_id must point at the site's sign-in page.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — sign in on a tab using the user's saved login — and scopes it by site. It also distinguishes itself from generic form-filling tools by noting it locates username/password/one-time-code fields itself.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit preconditions (open the site's sign-in page first), fallback guidance when no saved login exists (run `ascended-browser login add` or `signin <url>`), and a routing rule to skip browser_observe because the result already carries a `page` snapshot.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.