google_youtube_subscriptionsList the YouTube channels a user subscribes to, with account selection and pagination, so AI agents can retrieve subscription data without manual browsing.
List the channels the user subscribes to.
| Name | Required | Description | Default |
|---|---|---|---|
| account | No | Account nickname to use. | |
| pageToken | No | Token from a previous page's nextPageToken. | |
| maxResults | No | Max results (default 50). |
Changes observed during successful MCP inspections.
v0.1.95Input schema / properties / pageTokenAdded value: +{
+ "description": "Token from a previous page's nextPageToken.",
+ "type": "string"
+}v0.1.30Input schema / additionalPropertiesRemoved value: -falsev0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states 'List the channels the user subscribes to,' implying a read operation but omitting any details about authentication requirements, pagination behavior, return format, or rate limits.
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 a single, front-loaded sentence with no wasted words. It is as concise as possible for stating the core action, though it could add minimal value with one more sentence of context without becoming bloated.
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?
There is no output schema and no annotations. While the tool is a simple read-only list operation, the description does not explain what the list returns (e.g., channel objects) or how pagination works, leaving the agent to infer these from the schema parameters alone.
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 all three parameters (account, pageToken, maxResults) are already well documented in the schema. The description adds no meaning beyond the schema, which is acceptable given the high coverage, so the baseline 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 uses the specific verb 'List' and the resource 'channels the user subscribes to,' which clearly identifies the operation. It implicitly distinguishes itself from siblings like google_youtube_my_videos and google_youtube_list_playlists by focusing on subscriptions, though it does not explicitly name alternatives.
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 no guidance on when to use this tool versus alternatives, no prerequisites, and no exclusions. The agent must infer usage from the tool name and sibling list.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.