create_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. It only states the basic action and does not disclose behaviors such as whether mentions trigger notifications, what happens if the thread is closed, or whether shareId is required for certain contexts. Since it's a mutation tool, it should clarify side effects or prerequisites, but it doesn't.

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?

One concise sentence that uses a clear verb and object. No fluff, no repetition of what's in the schema. It is appropriately sized for a simple tool.

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, no output schema, and 4 parameters, the description is thin. It doesn't indicate whether a thread must be open, how mentions are processed, or what the return value is. The high schema coverage helps, but behavioral context is missing, making it incomplete for an agent to use it safely.

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 coverage is 100%, so all four parameters have descriptions in the schema. The description does not add extra meaning beyond what the schema provides, but per the rubric, with high coverage, baseline is 3. It doesn't explain how mentions or shareId relate to the comment creation, but the schema descriptions are adequate.

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 'Add a comment to an existing thread' clearly states the action (add) and the resource (comment to an existing thread), distinguishing it from sibling tools like create_comment_thread and update_comment. However, it lacks explicit mention that it is a comment on a thread, not a thread itself, which is implied but could be clearer.

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 implies usage context: it is for adding a comment to an existing thread, meaning a thread must already exist. It doesn't explicitly mention alternatives or when not to use it, but the context is clear enough from the phrasing. Sibling tools like create_comment_thread and list_comment_threads provide alternatives, but no explicit 'use this instead' guidance is given.

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