Type text

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

Annotations only declare readOnlyHint=false and openWorldHint=true; the description adds substantial behavioral detail beyond that — one trusted key event per character, IME-style commitment for non-US characters, and the >200 character paste-mode threshold unless slowly=true. It also discloses that line breaks are inserted as text rather than triggering Enter, which is a real behavioral gotcha.

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?

Front-loaded with the core action, then layered with mechanics, threshold, and escape hatches — every clause carries information. It is dense to the point of being a single run-on paragraph, which slightly hurts scanability.

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?

A 6-parameter mutation tool with no output schema, yet the description covers mechanics, the long-text fallback, line-break behavior, submit, and clear. It does not cover failure modes such as a missing or stale ref, or what happens when no element is focused, which an agent would need to recover from errors.

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 the baseline would be 3, but the description adds meaning the schema lacks: the 200-character threshold at which typing degrades into a paste, and the slowly=true override that forces key-by-key even for long text. It reinforces submit/clear semantics already in the schema rather than duplicating them.

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 ('Types text into an element (by ref) or into the focused element') and scopes the target precisely. It also names a sibling (press_key) for the Enter-key case, so an agent can distinguish the two without opening schemas.

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 clear routing guidance for the Enter case ('use submit=true or press_key to press Enter') and tells the agent it can clear first. It does not, however, say when to prefer this over sibling fill_form, or when typing is inappropriate versus evaluate/set-value approaches.

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