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

Beyond the annotations, it discloses the ownership restriction, that the entire body is replaced, that mention tokens trigger notifications, and that the updated comment is returned. These are material behavioral details not captured by readOnlyHint, idempotentHint, or destructiveHint.

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 front-loaded with the action and ownership constraint, then moves efficiently through replacement behavior, mention syntax, and return value. The example earns its place by illustrating a non-obvious token format.

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 two-parameter mutation with rich annotations, the description covers ownership, replacement semantics, mention syntax, and return behavior. Nothing important for correct invocation is missing.

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%, but the description adds essential meaning for the body parameter: the exact @[Display Name](userId) mention syntax, the requirement for an integer id, and the consequence that plain names notify nobody. That is substantial parameter semantics 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 states a specific verb and resource: "Rewrite one of the caller's OWN comments." It distinguishes this from add_comment and delete_comment by making clear it replaces an existing comment body, and it adds the ownership constraint.

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?

It clearly says when editing is allowed (only the caller's own comments) and explains the mention workflow needed when editing. It does not explicitly name add_comment or delete_comment as alternatives, but the operation boundary is otherwise clear.

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