generate_thumbnail

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

No annotations provided, so description must convey behavior. Only states a read-like operation ('grab') but doesn't disclose side effects, required permissions (e.g., transcript availability), or whether this modifies state. For a tool generating a thumbnail, more context is needed.

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?

Extremely concise, with action and details front-loaded. However, it sacrifices necessary context for conciseness, making it too brief for full understanding.

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 tool has two parameters and an output schema, the description is too sparse. It doesn't explain return values, parameter roles, or prerequisites. Incomplete for a new user to confidently invoke.

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 description must explain parameters. Only 'title' is implied via 'title overlay', but 'project_id' is unexplained. The relationship between parameters and functionality is unclear, especially for 'project_id'.

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?

Clearly states the action ('grab') and resource ('thumbnail'), with specific details: mid-frame, title overlay, from transcript. Unambiguous and distinct from siblings like 'generate_thumbnails' (plural).

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 on when to use this tool versus alternatives. Does not mention when not to use, prerequisites, or whether to prefer other tools like 'generate_thumbnails' for batch operations.

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