Extract subtitles with timestamps from Bilibili videos to access multilingual content and transcriptions for analysis or accessibility.
Get subtitles from a Bilibili video
Args:
url: Bilibili video URL, e.g., https://www.bilibili.com/video/BV1x341177NN
Returns:
List of subtitles grouped by language. Each entry contains subtitle content with timestamps.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true; the description adds value by specifying the return structure (list grouped by language with timestamps) beyond the annotations, but does not disclose other behaviors like rate limits or auth.
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 concise (5 lines) and front-loaded with the purpose, but the Args/Returns formatting could be more streamlined; still efficient.
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 simple read tool with one parameter and no output schema, the description covers input format and output structure adequately, though it omits potential errors or prerequisites.
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 coverage is 0%, so the description compensates by explaining the 'url' parameter with an example and format, adding meaning beyond the bare schema definition.
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 explicitly states 'Get subtitles from a Bilibili video' and provides an example URL, making the tool's purpose clear and distinguishing it from sibling tools like get_comments and get_danmaku.
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?
No guidance on when to use this tool versus alternatives; it does not mention context for use or exclusion criteria, leaving agents to infer from the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.