Unsubscribe from a Channel

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

The description discloses destructive and irreversible nature, requiring confirm=true to execute. It explains dry-run behavior (refuses with explanation) and the 204 response on success. Annotations already set destructiveHint=true; description adds context about what gets destroyed and how to safely test.

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 with clear sections: overview, important note, args, returns, examples, common errors. Every sentence provides value, no redundancy. It's appropriately sized for the tool's complexity.

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 2-parameter tool with no output schema, the description fully covers behavior, returns (204 with confirmation message), and error handling. It anticipates common mistakes (wrong ID, auth issues) and provides resolution steps.

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?

Input schema has 2 parameters with detailed descriptions. The description adds meaning beyond schema: explains that subscriptionId is the 'id' field from list results (not channelId), and confirm default false is a safety. Examples illustrate usage. Schema coverage is 100%, but description adds critical context.

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 action ('Remove a subscription') and the resource ('for the authenticated user') using the YouTube Data API v3 subscriptions.delete endpoint. It distinguishes from sibling tools like youtube_subscribe by specifying it's for unsubscribing and requiring a subscription resource ID, not a channel ID.

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 explicit when-to-use instructions (must have subscription ID from youtube_list_subscriptions, not channel ID), when-not-to-use (wrong ID leads to 404), and alternatives (call youtube_list_subscriptions first). It includes important prerequisites, dry-run behavior, and common errors.

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