browser_type

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

With no annotations, the description carries the full burden and does disclose useful behavior: character-by-character typing, IME composition for Hangul, and that the value is verified after typing. It does not disclose what happens when verification fails (retry? throw? return a flag), whether typing is destructive to existing content, or permission/auth constraints on a browser mutation.

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?

Two sentences, front-loaded with the core action and zero wasted preamble. The second sentence is heavily nested with parentheticals, but every clause (Enter rule, target kinds, exclusion list) carries actionable 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?

For an 8-parameter mutation tool with no annotations and no output schema, the description covers the typing mechanism and one edge case but leaves gaps an agent must guess at: how verification results are reported, what `clear` does, and how ambiguous name/role matches are resolved via `index`.

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 only 50%, and the description compensates only indirectly: the search-field heuristic implies how `name`/placeholder targeting works. Undocumented parameters remain unexplained — notably `clear` (does it wipe the field first?), `index` for ambiguous matches, and `role`, which materially change the outcome of the call.

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 ("Type text into a field") plus distinguishing mechanics (key-by-key, IME composition for Hangul, post-type verification). It is clearly not a click/read/run tool, though it never names a sibling explicitly to route against (e.g. browser_run or browser_click for non-field interaction).

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?

The description gives one concrete conditional rule (trailing newline presses Enter, and only in search-like fields, with an explicit exclusion list: e-mail/phone/comment/code). That is real when-not guidance about input content, but there is no guidance on choosing between this tool and browser_click, browser_run, or browser_search.

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