Extract a YouTube transcript

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

Beyond annotations, it discloses the sequential fallback behavior, reporting of failures, and caching semantics. This provides useful operational context that annotations (readOnlyHint false, idempotent false) do not capture, such as why a request might be expensive the first time.

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?

Three sentences, each providing distinct value: the main function, the fallback/reporting behavior, and the caching note. No wasted words.

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 moderate complexity, the description covers the core behavior, fallback chain, and cache characteristics. An output schema exists, so it needn't explain return values, but it might have mentioned output language or format limitations. Still, it's reasonably 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 0%, so the description must compensate. It implies the URL as the video identifier and mentions caching (use_cache), but doesn't explicitly explain the parameters or their formats. It adds some meaning but leaves gaps.

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 starts with a specific verb+resource: 'Get the transcript for one YouTube video.' It clearly differentiates from sibling tools like archive_batch or summarise_pending by focusing on transcript extraction. The scope is unambiguous.

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 explains the fallback mechanism (caption APIs, yt-dlp, local speech-to-text) and notes that caching makes repeated calls free. This gives an implied usage context, though it doesn't explicitly state when to choose this tool over alternatives or any exclusions.

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