get_info_durationstring The length of the video. The property value is an ISO 8601 duration. Group: Specific video Info. Billing per call: 1 Credits.
| Name | Required | Description | Default |
|---|---|---|---|
| id | No | Youtube video ID in expected format `(/^[a-zA-Z0-9-_]{11}$/)` |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so the description carries the burden. It discloses the output format (ISO 8601 duration) but does not state whether the operation is read-only, requires authentication, or any potential side effects. 'Billing per call: 1 Credits' is a cost note, but the overall behavioral transparency is minimal.
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, one sentence with a link, and front-loads the core purpose. It does not waste words and is appropriately structured.
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 is simple with one parameter and no output schema, so the description is mostly adequate. However, it lacks information about when to use this tool (e.g., for a specific video vs. a list), and since there are many sibling tools, it could clarify that this is for a single video's duration. Given the simplicity, it's acceptable but could be stronger.
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?
The schema describes the 'id' parameter well with a regex validation pattern, and the description doesn't add further parameter details. Since schema coverage is 100%, a baseline of 3 is appropriate. The description does not confuse but also adds no extra meaning beyond the schema.
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 tool returns the video duration as an ISO 8601 duration string. It is specific about the resource (video) and property (duration), and the sibling tools show this is one of several get_info_* tools, so the purpose is distinct.
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 versus alternatives. It only identifies the group 'Specific video Info' and billing. It doesn't mention that this tool requires a video ID or that it's for a specific video, and there is no alternative comparison.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a distinct purpose. get_info retrieves overall metadata, while get_info_* variants target specific fields (title, duration, etc.), and get_download/get_mux handle downloading and merging. No two tools overlap in functionality.
All tools follow a consistent 'get_' prefix, with metadata fields using the 'get_info_<field>' pattern. The variation for get_download and get_mux is clear and does not break the overall naming scheme.
With 13 tools, the server is within the ideal 3-15 range for a specialized YouTube downloader. The number is reasonable given the need for granular metadata access alongside download and mux operations.
The toolset covers core download, muxing, and a wide range of metadata fields (e.g., title, duration, thumbnails, view count). Minor omissions like upload date or like counts represent a small gap, but the main functionality is well covered.