get_youtube_subtitles_download

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

No annotations are provided. The description discloses the credit cost (3 credits) and implies a read operation, but lacks details on authentication requirements, rate limits, or error behavior when subtitles are unavailable. It provides some value beyond annotations but is not fully transparent.

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 two concise sentences: the first states the purpose, the second provides a critical usage constraint and cost. No unnecessary words, well front-loaded.

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?

The tool has no output schema, but the description does not hint at the output format (e.g., SRT, VTT). It also omits error cases. However, it covers key usage constraints and cost, making it moderately complete for a simple tool.

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%, with both parameters (videoId and language) fully described in the schema. The description adds no additional parameter meaning, so the baseline score of 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?

The description clearly states the action (download subtitle track), the resource (specific YouTube video), and distinguishes itself from sibling tools like get_youtube_subtitles_meta by specifying 'Download' vs 'Meta', and explicitly says 'pass videoId, not channelId' to avoid channel-level confusion.

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 context that it is per-video with a videoId, and mentions a credit cost, but does not specify when to use this tool versus alternatives like get_youtube_subtitles_meta. No explicit when-not-to-use guidance is given.

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