youtube_list_captions

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

With no annotations, the description must carry the burden of disclosing behavioral traits. It mentions OAuth requirements and the ownership restriction, which are important. However, it does not disclose expected output format, pagination, or error behavior. The description adds some value but leaves gaps for a listing tool.

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 concise and front-loaded, with the purpose stated first, followed by operational requirements and arguments. It uses no unnecessary words and is directly scannable. The structure is optimal for an agent to parse.

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's simple nature (list captions) and the sparse schema/annotations, the description covers the essential operational context (auth, ownership). However, it lacks any indication of the return value or what constitutes a 'caption track,' which is important since there is no output schema. The description is minimally complete but not fully self-sufficient.

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?

The input schema has one parameter 'video_id' with no description, and schema description coverage is 0%. The description adds a minimal restatement: 'video_id: YouTube video ID.' This is essentially redundant with the parameter name and does not provide details like format, example, or constraints. The description fails to sufficiently compensate for the schema's lack of documentation.

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's purpose: 'List available caption tracks for a video you own.' It specifies the action (list), the resource (caption tracks), and the scope (videos you own). This distinguishes it from related tools like youtube_get_transcript, which fetches transcript content.

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 provides clear context: 'Requires OAuth' and 'Only works for videos on the authenticated user's channel.' These constraints inform when to use the tool, but it does not explicitly mention alternatives or exclusion conditions compared to sibling tools. Still, the context is clear enough for an agent to infer appropriate usage.

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