chrome_fill_form

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. It only states the basic action without mentioning side effects, default behavior (e.g., clear_first defaults to true), error handling for invalid selectors, or whether fills are transactional. For a mutating operation, 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?

The description is a single, front-loaded sentence with zero wasted words. It efficiently states the core purpose. It could arguably include a bit more about the clear_first default without becoming verbose, but as is, it is concise and well-structured.

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?

Although the schema is descriptive, the tool description alone is insufficient for a mutating tool with multiple parameters and behavioral nuances. It does not mention the clear_first flag, behavior when selectors are missing, or any page-state requirements. The context from siblings helps but is indirect. The description does not adequately prepare an agent for safe invocation.

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?

The input schema covers 100% of parameters with descriptions, so the baseline is 3. The tool description adds no additional meaning beyond what the schema already provides; it merely reiterates the 'fill multiple fields' concept. No parameter-level insight is offered beyond the structured schema.

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 'Fill multiple form fields at once' uses a specific verb ('fill') and resource ('form fields'), and the phrase 'multiple... at once' clearly distinguishes it from sibling tools like chrome_type, which presumably handles single fields. It is unambiguous and immediately conveys the tool's scope.

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 implies usage for bulk filling of form fields but does not explicitly state when to use this tool versus alternatives like chrome_type for single fields. The context is clear from the phrasing and sibling tool names, but there is no explicit exclusion or alternative guidance, so it falls at 'implied usage' rather than 'clear context with exclusions'.

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