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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description is not required to restate those. It adds value by specifying project scoping ('acts only on the explicit project_id'), that it returns the project identity, and that it does not return pictures. This goes beyond annotations and helps the agent understand the tool's boundaries.

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 three concise sentences with no filler. It front-loads the critical project-scoping constraint and keeps the reader's attention on the key facts. Each sentence adds distinct information, making it efficient and readable.

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?

For a read-only tool with three parameters and no output schema, the description leaves gaps: it does not specify the return format (e.g., array of timestamps), whether start and end are inclusive, or what happens if they are omitted. It also does not mention any limits or pagination. These are important for an agent to call it correctly, especially without an output schema.

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 only 33% (only project_id has a description). The description mentions 'for a time range' but does not clarify the units, format, or optionality of start and end. It adds no detail about these parameters beyond the schema, so it fails to compensate for the low schema coverage.

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 returns 'Shot boundaries (scene changes — where transitions may land) for a time range', and it is project-scoped. It also distinguishes itself from siblings by noting it returns the project identity and that the actual picture is in filmstrips and look_at, which helps an agent know this is not the tool for frames.

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 gives a hint about when not to use it ('The PICTURE itself is in your filmstrips and look_at'), implying look_at is for pictures. However, it does not explicitly name alternative tools for other purposes, nor does it state clear conditions for when to choose this over get_editorial_map or get_video_info. Usage guidance is implied rather than explicit.

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