pdf_merge

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

No annotations are provided, so the description carries the full burden. It states the action ('merge') but lacks behavioral details such as whether it overwrites existing output files, handles errors (e.g., invalid PDFs), requires specific permissions, or has performance constraints. This leaves significant gaps for an agent to understand operational risks.

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, efficient sentence that directly states the tool's function without unnecessary words. It's front-loaded and wastes no space, making it easy for an agent to parse quickly.

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 complexity of merging files (a mutation operation) with no annotations and no output schema, the description is insufficient. It doesn't cover error handling, output format details, or side effects, leaving the agent with incomplete information to use the tool safely and effectively.

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%, with clear parameter descriptions in the schema itself (e.g., 'Array of PDF file paths to merge (in order)'). The description adds no additional semantic context beyond what the schema provides, so it meets the baseline for high coverage without extra value.

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 verb ('merge') and resource ('multiple PDF files into a single PDF'), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like pdf_reorder or pdf_create, which might involve similar PDF manipulation but serve distinct purposes.

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. It doesn't mention prerequisites (e.g., file accessibility), exclusions (e.g., not for merging non-PDFs), or comparisons to siblings like pdf_reorder (which might reorder pages without merging files).

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