upload_texttrack

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

Annotations already mark the operation as read-write and non-idempotent; the description adds the auth prerequisite ('Needs the upload scope') and clarifies that the track is created from user-supplied VTT. No contradiction with annotations.

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?

Two sentences contain the essential purpose and a prerequisite with no filler. The action is front-loaded, and the auth note is concise.

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?

Moderate complexity (6 params, 4 required) is fully covered by the schema, and the description supplies purpose plus auth scope. No output schema exists, but for a create operation the agent has enough to call it correctly; an explicit pointer to update_texttrack for modifying an existing track would make it fully complete.

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 schema already documents all six parameters. The description's reference to WebVTT content merely aligns with the vtt param and adds no new parameter-level information; baseline 3 is appropriate.

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?

States a specific action — 'Add a caption or subtitle track to a video' — and the input source (WebVTT content). The verb 'Add' clearly differentiates it from siblings like update_texttrack, list_texttracks, and delete_texttrack.

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 clear context for when to use it: when the caller is supplying WebVTT content and needs upload scope. It does not explicitly name alternatives or exclusions, so it stops short of a 5.

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