get_subtitles

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

Annotations indicate readOnlyHint=true and openWorldHint=false, which the description does not contradict. The description adds valuable context beyond annotations by specifying the return format ('List of subtitles grouped by language' with 'subtitle content with timestamps'), enhancing behavioral understanding without repeating annotation information.

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 well-structured and front-loaded with the core purpose, followed by concise sections for Args and Returns. Every sentence adds value without redundancy, making it efficient and easy to parse for an AI agent.

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 low complexity (1 parameter, no output schema), the description is largely complete: it covers purpose, parameter semantics, and return format. However, it lacks explicit usage guidelines compared to siblings, which slightly reduces completeness for an agent needing to choose between tools.

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?

With 0% schema description coverage, the description fully compensates by clearly explaining the single parameter 'url' as a 'Bilibili video URL' and providing an example. This adds essential meaning beyond the bare schema, ensuring the parameter's purpose and format are understood.

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 specific action ('Get subtitles') and target resource ('from a Bilibili video'), distinguishing it from sibling tools like get_comments and get_danmaku which handle different video content aspects. It provides a concrete example URL, making the purpose 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 implies usage for extracting subtitles from Bilibili videos but does not explicitly state when to use this tool versus alternatives like get_comments or get_danmaku. No guidance is provided on prerequisites, limitations, or scenarios where this tool is preferred over others, leaving usage context inferred rather than defined.

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