merge_pdfs

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

No annotations are provided, so the description carries full burden for behavioral disclosure. It does not mention whether the operation is read-only, any side effects, error handling for invalid PDFs, or output format. The description is too minimal for a merge operation.

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 just two sentences, both essential and front-loaded. No unnecessary words or repetition. It meets the conciseness standard perfectly.

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 a single parameter and no output schema. The description covers input format and count but omits output format (e.g., returning merged PDF as base64), error cases, and any ordering guarantees beyond 'in order'. For a merge tool, this 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?

Schema description coverage is 100% for the single parameter, so baseline is 3. The description adds 'in order' which is useful but largely redundant with the schema. No further semantic detail is provided beyond what the schema already states.

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 action (merge), resource (PDF files), and constraints (2-20 files, base64-encoded). It distinguishes from sibling tools like split_pdf and compress_pdf, making the tool's purpose unambiguous.

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 implies when to use this tool (combining multiple PDFs into one) and specifies input format and size limits. However, it does not explicitly state when not to use it or mention alternatives, though the context from the sibling list suggests differentiation.

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