calculate_engagement

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

With no annotations, the description carries full burden. It states what it calculates but does not disclose if authentication is required, the output format, or potential failure cases (e.g., private videos). The agent is left guessing about side effects and response structure.

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 sentence, front-loaded with the action and resource, listing the specific metrics. Every word is necessary and no redundancy.

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 simplicity (1 param, no output schema), the description covers the tool's purpose minimally. However, it could benefit from mentioning the output structure or that views are the denominator. In context of sibling tools with richer descriptions, it feels slightly under-specified.

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 the baseline is 3. The description adds 'YouTube video URL or video ID', but this is already in the schema. No additional semantics like format validation or constraints are provided.

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 'calculate' and the resource 'engagement metrics for a YouTube video', specifying the exact metrics (like rate, comment rate, overall engagement rate). This effectively distinguishes it from sibling tools like get_video_metadata or get_channel_info.

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 usage for obtaining engagement rates but provides no explicit guidance on when to use this tool versus alternatives, nor any conditions or prerequisites. It lacks exclusions like 'do not use if you need raw counts'.

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