sendVideoNote

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

With no annotations, the description carries the full burden. It discloses the format support (rounded square MPEG4, up to 1 minute) and the success return value (the sent Message). It does not explain failure behavior, permission requirements, upload mechanics, or other operational details, but it does provide some useful behavioral context beyond the name and schema.

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 only two sentences and front-loads the key format constraint before the action. It is concise and readable, though the phrase 'Send video messages' is somewhat redundant with the tool name and could be replaced with more differentiating information.

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 complex tool with 15 parameters, nested objects, and no output schema, the description is thin. It does mention the return value, and the schema covers parameters, but there is no guidance on upload strategies, error cases, or relationship to sibling send tools. It is adequate but not complete for an agent selecting among many similar methods.

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 structured data already documents all parameters. The description adds no parameter-level semantics beyond the format constraints, which are context for the video_note parameter. This meets the baseline for high schema coverage, with no bonus for additional insight.

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 states a clear action and resource: 'Send video messages' for video notes. It also provides the distinguishing format constraints (rounded square MPEG4, up to 1 minute), which helps separate it from sendVideo. However, it never explicitly names a sibling or highlights the difference with sendVideo, so a small gap remains.

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?

There is no guidance on when to use this tool versus alternatives like sendVideo, sendAnimation, or sendVoice. The format description implies it is for video notes, but it does not state this explicitly or mention when not to use it. With 15+ sibling send tools, this leaves the agent to infer the intended usage.

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