ffmpeg_merge

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

No annotations are present, so the description bears full responsibility for disclosing behavior. It only states the basic operation and mentions an optional output path, but omits critical behavioral details like file format compatibility, codec requirements, error handling, or behavior when files have different resolutions.

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, using a clear structure (Args/Returns). Two sentences for the main description and two for parameters, but no unnecessary information. It could be slightly more compact but is well-organized.

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?

While the description covers the minimal essentials for merging files, it lacks completeness regarding supported formats, order enforcement, error conditions, and return value details. An output schema exists but the description does not leverage it to explain the output path format.

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 coverage is 0%, so the description adds significant value beyond the schema. It explains that file_paths is a list of paths in order, and output_path is optional with a default behavior. This provides necessary context for correct invocation.

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 purpose with a specific verb ('concatenate') and resource ('multiple video files into one'). It effectively distinguishes from sibling tools like ffmpeg_trim, ffmpeg_compress, etc., which have different operations.

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 the tool is for merging video files in order, but it lacks explicit guidance on when to use it versus alternatives (e.g., when to use ffmpeg_merge vs ffmpeg_convert or other tools). No 'when not to use' or prerequisite information is provided.

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