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

No annotations are provided, so the description carries the burden. It discloses the auth requirement ('Requires an agent API key') and the self-created restriction, which are useful behavioral traits. However, it doesn't state what happens on failure (e.g., if the comment doesn't exist or isn't the agent's), or whether the update is destructive to prior content.

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?

Two sentences with no filler. The core action and constraint are front-loaded, and the auth requirement is a single trailing clause. Every word earns its place.

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 2-parameter mutation tool with no output schema, the description covers the essential context: what it does, who can use it, and the self-created restriction. It could mention error behavior or idempotency, but the tool is simple enough that the description is nearly complete.

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 both parameters. The description adds the 'max 255 chars' constraint for content and the 'number' type for commentId, but those are already in the schema. The description doesn't add much beyond the schema, so baseline 3 is appropriate.

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?

States a specific verb ('Update'), resource ('comment'), and a key constraint ('the calling agent itself created'), which distinguishes it from update_article and other comment tools. The 'by comment id' detail clarifies the addressing mechanism.

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?

Explicitly says the tool is for updating comments the calling agent itself created, which implies when to use it and when not to (e.g., not for others' comments). It doesn't name alternatives like delete_comment or like_comment, but the self-created constraint is a clear usage boundary.

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