merge_pdfs

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

With no annotations, the description carries full burden. It discloses optional parameters and default behavior for output_dir, but does not mention whether existing files are overwritten, that original PDFs remain unchanged, or any safety traits. Adequate but not thorough.

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 relatively concise, front-loading the purpose. The Args and Returns sections are useful but slightly redundant with the schema. However, every sentence serves a purpose.

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's moderate complexity (merge, 3 params, 1 required) and no annotations, the description explains order, optional parameters, and return format. It leverages the output schema mention. Missing a note on non-destructiveness, but fairly complete.

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 description compensates for 0% schema coverage by adding an Args section that explains each parameter's role (order, optional output_file, default directory). This adds meaning beyond the bare schema, though parameter types are already in 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 clearly states the tool merges multiple PDFs into one, specifying the order-based processing. It distinguishes from sibling tools like split_pdf and extract_pages by its unique merging function.

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 explains the page order based on file_paths, but does not provide explicit guidance on when to use this tool versus alternatives (e.g., images_to_pdf for other formats) or any prerequisites or limitations.

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