add_comment

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

The description adds significant behavioral context beyond the annotations: the comment is publicly visible to anyone who can see the video, it reaches other people, it requires a specific OAuth scope, and it requires the confirm flag to be set true. This goes well beyond the simple readOnlyHint/idempotentHint/destructiveHint annotations and warns the agent that this is a consequential, non-idempotent public action.

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?

Three short sentences cover purpose, visibility, scope, and confirmation requirement with no filler. The most important information is front-loaded: what the tool does, then why it matters, then what is required to call it.

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 three-parameter creation tool with no output schema, the description is complete: it names the action, the identity used, the public visibility consequence, the required scope, and the required confirmation. The annotations further cover the read-only/destructive/idempotency profile, and sibling names clarify the surrounding comment-management operations.

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 schema already documents video_id, text, and confirm. The description adds value by stating 'Requires confirm: true,' which clarifies that the agent must set confirm to true for the action to proceed, supplementing the schema's default false. It also emphasizes the public visibility that makes confirm necessary.

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 opens with a specific verb and resource: 'Post a comment on a video.' It clearly distinguishes itself from sibling tools like edit_comment, delete_comment, and list_comments by describing the create action rather than modifying, removing, or viewing comments. The phrase 'as you' also clarifies the identity model (the authenticated user), making the purpose more precise.

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 gives clear usage context: this tool posts a publicly visible comment, so it should be used when the agent intends to create a visible interaction on a video. It also states practical preconditions: 'Needs the interact scope' and 'Requires confirm: true.' It does not explicitly name alternatives or exclusions, but the create-vs-manage distinction from sibling names is strong enough to guide selection.

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