Add text overlay

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

No annotations are present, so the description carries the full burden of behavioral disclosure. It only mentions the ability to limit text to a time range, but does not state whether the operation creates a new file, overwrites the input, preserves audio, or what happens if no start/end is given (presumably text appears throughout the entire video). These are important behavioral traits for a video editing tool.

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 extremely concise, consisting of two short sentences. It front-loads the primary purpose and adds the time-range detail without unnecessary words or repetition.

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?

With 9 parameters and no output schema, a richer description is needed. The current description only covers the general purpose and optional time range, but does not explain return values, error behavior, output file handling, or any processing details like re-encoding. This is inadequate for a tool with such complexity.

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%, so all parameter semantics are already documented in the schema. The description adds no extra parameter meaning beyond the mention of an optional time range, which maps to the start and end parameters. This meets the baseline but does not enhance it.

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 draws text on a video and gives examples (caption, title, label). It also mentions the optional time-range limitation. However, it does not explicitly distinguish itself from sibling tools like burn_subtitles or add_watermark, which could also involve text placement.

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 provided on when to use this tool versus alternatives. It does not mention that burn_subtitles might be for subtitle files or that add_watermark is for watermarking, leaving the agent without clear selection criteria.

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