Youtube Get Timestamped Transcript

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

No annotations are provided, so the description carries the full burden, and it does: truncation policy ('truncated at RESPONSE_LIMIT by cumulative text length'), pagination contract (`next_cursor` is the next segment index, `null` means complete), cost ('costs no Data API quota'), and inherited caching/failure behavior from the sibling. It even warns that `duration` is on-screen time, not speech length, because segments overlap.

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?

Front-loaded with purpose and return shape, then usage routing, then pagination/limits. Every sentence carries distinct information; nothing is restated from the title or schema.

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 transcript fetch with an output schema present, the description adds everything an agent needs beyond the schema: segment field semantics, truncation/pagination behavior, sibling routing, and quota cost. No meaningful gap remains apart from the undocumented `languages` parameter.

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 0%, so the description must compensate. It explains the pagination parameter's meaning and lifecycle ('the index of the next segment — pass it back to continue; null means you have all segments') and demonstrates `video_id` usage in the deep-link template. The `languages` parameter is never mentioned, leaving one of three parameters undocumented.

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 verb and resource (fetch a YouTube video's transcript as timed segments) and immediately defines the exact output shape `{text, start, duration}` with unit semantics. It explicitly distinguishes itself from the sibling `youtube_get_transcript`, so an agent can choose between them without opening either schema.

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?

Explicit routing: 'Use this to build chapter lists or deep links ...; use `youtube_get_transcript` when you only need the words.' It also gives the operational condition for continuing pagination ('pass it back to continue'). Both when-to-use and the named alternative are present.

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