form_filler

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

With no annotations, the description must disclose behavioral traits. It only states the basic action and does not mention whether the original file is modified or a new file is created, whether the operation is destructive, or if any permissions are required. The output_name parameter suggests output behavior, but this is not explained in the description.

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, concise sentence with no superfluous content. It directly conveys the core functionality without unnecessary elaboration.

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?

The description is too sparse for a tool that modifies PDF files. It does not mention whether a new file is created, how output_name works, what happens to the original file, or any side effects. Given the complexity of form-filling (field matching, output handling), the description leaves significant 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 has 100% coverage with meaningful descriptions for each parameter. The description adds no additional parameter details, but since the schema already documents all three parameters clearly, the baseline score of 3 is appropriate.

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's function: filling form fields in a PDF with provided values. It uses a specific verb ('fill') and resource ('form fields in a PDF'), making the purpose unambiguous. It does not explicitly distinguish from sibling tools like form_creator, but the action is distinct enough.

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 no guidance on when to use this tool versus alternatives, nor does it mention any prerequisites or limitations. It does not explain how to handle situations like missing fields or incorrect field names, leaving the usage context unclear.

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