Browser Fill

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. 'Fill a field with text' only implies a mutation of browser state; it doesn't state whether existing text is replaced or appended, what happens on selector failure, how timeout behaves, or whether a session must be active. For a mutation tool with zero annotation coverage, this is a significant gap.

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?

A single short sentence with no redundancy, so nothing is wasted. However, this is under-specification rather than efficient conciseness – the brevity reflects missing critical information, not disciplined selection of the most relevant 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?

For a 4-parameter browser automation tool with 25 siblings, no annotations, no output schema, and 0% schema coverage, this description is completely inadequate. An agent cannot determine selector syntax, timeout semantics, session requirements, or the return value. The tool needs materially more context to be called correctly.

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 description coverage is 0% – the schema property definitions carry no descriptions, so the description must compensate. It adds nothing about the parameters: no clarification of the selector format (CSS? XPath?), no timeout units or defaults, no note about how the value parameter behaves. Parameter names are inferable but not documented; the description provides no added meaning.

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 ('Fill a field with text'), which is clear about the action. However, in context of 25 sibling browser tools, it doesn't distinguish itself from browser_fill_form, browser_keyboard_type, or browser_click, all of which could plausibly enter text. The purpose is intelligible but undifferentiated.

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?

No guidance on when to use this tool vs alternatives like browser_fill_form (for multiple fields) or browser_keyboard_type (for typing). No exclusions, no context, no prerequisites like an active session. The agent must infer appropriate usage entirely from the name and siblings.

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