fill_form

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

No annotations are provided, and the description gives no behavioral details such as whether it simulates typing, sets values directly, clears existing content, triggers events, or handles errors. It simply restates the basic action without revealing important execution traits.

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 no redundant words. It efficiently conveys the core action, making it appropriately concise.

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?

Given the tool has two parameters, one being an array of nested objects, and no annotations or output schema, the description is insufficient. It does not explain selector syntax, behavior on invalid selectors, whether events are triggered, or any return value, leaving many gaps.

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 already covers both parameters with descriptions (page and fields). The tool description adds no additional parameter semantics beyond the word 'fill', so it meets the baseline for high schema coverage without adding extra 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?

The description clearly states the tool fills multiple form fields at once, using the verb 'fill' and scope 'multiple form fields at once'. This distinguishes it from sibling tools like type_text, which is for single fields, and click.

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 phrase 'at once' implies use when needing to fill several fields in a single operation, but the description does not explicitly state when to use this tool over alternatives like type_text, nor does it mention prerequisites or exclusions.

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