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

Annotations already mark this as non-read-only, non-idempotent, and non-destructive. The description adds meaningful behavioral context beyond those hints: the tool submits an async task, waits up to 240 seconds, and returns a job_id with a follow-up query action if the task is incomplete. It does not mention rate limits or authentication, but those are not critical for a simple async submission.

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?

A single front-loaded sentence states the core action, the input kind, and the post-submission behavior. There is no repetition of schema or annotation content, and every clause adds useful information.

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 one-parameter async submission tool with a rich output schema, the definition covers the input, the wait behavior, and the fallback job_id path. The only minor gap is that the description refers to '下一步查询动作' without explicitly naming the sibling polling tool bilibili_get_video_speech_text_job, but the output schema likely provides the exact follow-up action.

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%, so the input schema fully documents the bvid parameter, including format and invalid input. The description itself does not add parameter-level meaning beyond what the schema already provides, 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 a specific verb (提交/submit), a specific resource (Bilibili BV 号), and the exact task (P1 口播转文字). It distinguishes this tool from its sibling by_video_url variant by identifying the key input type as BV号, while the input schema further tells the agent what not to pass.

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/schema explicitly says to use this tool when a BV号 is available, and provides an explicit alternative: use by_video_url with a p parameter for P2 or later parts. It also explicitly excludes video links, aid, and user homepage links, giving the agent clear when-to-use and when-not-to-use guidance.

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