Merge Multiple PDFs

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

With no annotations, the description carries the full burden of disclosing side effects. It mentions 'via PDF4me /api/v2/Merge' hinting at an API call, but doesn't state whether it modifies inputs, requires network access, or creates output files and in what way. No details on permissions, overwriting behavior, or reversibility are provided.

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 sentence, front-loaded with the main action. It includes the input list and output path, but the API endpoint is extraneous for an agent. Overall, it is concise and easy to parse, earning a high score for structure.

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 no output schema or annotations, so the description must explain return values and behavior. It does not mention what the tool returns, how output_dir and output_file_name interact, or any error conditions. Given the relative simplicity of a merge operation, the description is still incomplete for an agent to use it safely.

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 mentions pdf_file_paths and request_doc_name, but 'output path' is ambiguous against the schema's separate output_dir and output_file_name parameters. It doesn't explain the purpose of request_doc_name or clarify the output parameter relationship, leaving the agent to rely on schema names alone. With 0% schema coverage, the description fails to compensate.

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 'Merge multiple PDF files into one', providing a specific verb and resource. It is distinct from siblings like merge_pdf_overlay, though it doesn't explicitly differentiate from that overlapping tool. The mention of 'via PDF4me /api/v2/Merge' adds technical detail but doesn't obscure the core purpose.

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?

No guidance is given on when to use this tool versus alternatives like merge_pdf_overlay or split_pdf. The description only states the action without context or exclusion criteria, leaving the agent without direction for tool selection.

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