create_fillable_forms

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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It only states the action without detailing side effects (e.g., whether the original PDF is modified, output behavior, authentication requirements, or error handling). The example annotations format is helpful but does not disclose the tool's operational behavior beyond the input structure.

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 concise and includes a helpful example annotation format. It is front-loaded with the core purpose and then supplements with the example. The reference link is extra but not harmful. It earns its place without being overly verbose.

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 tool has 6 parameters, 2 required, and no output schema. The description does not explain what the tool returns (e.g., the generated PDF URL or job status), nor does it mention prerequisites like using 'upload_file' for local files. Given the complexity, the description is incomplete for an agent to fully understand the tool's behavior and results.

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 schema description coverage is 100%, so the baseline is 3. The description adds value by providing a concrete example of the 'annotations' parameter format, showing fields like 'text', 'x', 'y', 'size', 'pages', 'type', and 'id'. This goes beyond the schema's generic description and clarifies how to structure the form elements.

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: 'Create new fillable form elements in a PDF document.' This is a specific verb (create) + resource (fillable form elements in PDFs), and it distinguishes from similar siblings like pdf_add_annotations_images_fields by focusing on form elements.

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 a clear context (creating fillable forms) but does not explicitly mention when to use this tool versus alternatives. There is no exclusionary guidance or mention of prerequisites. It is implied that this is the right tool for adding form fields, but no explicit alternatives are given.

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