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

It discloses that the tool replaces the existing value by default, supports pressEnter, and explains the difference between fill and press modes (one-shot vs real per-key events). This adds behavioral depth beyond the annotations, which only indicate read/write/destructive hints. No contradiction with annotations.

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 every phrase adds value (behavior, mode selection, specific use cases). No fluff or redundant repetition of schema details.

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?

Despite having 9 parameters and nested objects, the schema covers most details, and the description addresses the key behavioral variations. No output schema exists, but the description doesn't need to explain return values for an action like typing. Slightly missing explicit guidance on target selection, but the schema compensates.

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 high (89%), so the description doesn't need to explain every parameter. It adds valuable context for `mode` (when to use 'press') and `pressEnter`, augmenting the schema's definition. This justifies a score above the baseline.

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?

The description clearly states the action (enter text) and the resources (input, textarea, contenteditable), distinguishing it from sibling tools like browser_click or browser_press_key. It also mentions key behaviors like replacing existing value and optional submission via pressEnter.

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 provides context on when to use press mode (pages that listen for keydown, autocompletes, search-as-you-type) and mentions pressEnter for submission. It does not explicitly name alternative tools or exclusion criteria, but the context is clear enough for an agent to decide.

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