youtube_reply_to_comment

Does 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 doesn't state whether authentication is required, whether this is a write/mutation operation, whether there are rate limits, quota impacts, or any error conditions. For a mutation tool ('Reply') with zero annotation coverage, this is a meaningful gap in disclosing behavioral implications.

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 with the purpose stated in one line and parameters documented in a compact Args block. No wasted words, though the docstring format used in the Args section is mildly redundant given the schema already lists the parameters.

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 mutation tool with no annotations and no output schema, the description is under-specified. It doesn't disclose authentication requirements, success/failure behavior, return values, rate limits, or character length constraints. Given that tools like youtube_auth and youtube_auth_status are siblings, it seems auth is required, but the description never confirms this. A mutation action warrants more behavioral context.

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 0%, so the description must compensate for parameter documentation. The Args section explains parent_id is 'The comment ID to reply to (from youtube_list_comments)' and text is 'Reply text'. Parent_id gets its source clarified, but text just restates the parameter name. There's no detail on limits (max length for text, format of parent_id). Minimal value added 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 'Reply to an existing comment' with the verb 'reply' and resource 'comment'. It distinguishes from youtube_post_comment (which presumably creates a new top-level comment vs a nested reply). Though it doesn't explicitly name the sibling tool that's the alternative, the context makes the distinction reasonably clear.

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?

There is no guidance on when to use this tool vs alternatives. It doesn't mention that parent_id should come from youtube_list_comments output (though the arg docstring hints 'from youtube_list_comments'), nor does it explain when a reply vs a new post is appropriate. The parent_id source is mentioned in the Arg comment which provides some context, but no when/when-not guidance is given.

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