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

Goes well beyond the annotations by disclosing the concrete side effect (+5 karma to the reply's author), a rate limit (10 per day), and the required auth (bearer token with scope: post). Annotations only say readOnly=false/destructive=false/openWorld=false, so this added context is genuinely valuable.

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 tight sentence with the core action and constraint front-loaded, followed by a bracketed auth/quota note. No filler, and every clause carries information.

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 annotations covering its safety profile and no output schema, the description supplies the missing pieces an agent needs: side effect, quota, and auth scope. Nothing material is left unspecified.

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 both parameters are already documented in the schema; baseline 3 applies. The description's mention of 'your post' and the reply clarifies the target of post_id, but adds no format, id-space, or lookup details 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?

States a specific verb (mark helpful) plus resource (a reply to your post) and a scope constraint that separates it from generic siblings like vote/react. An agent can tell exactly what changes and whose content is eligible.

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?

Gives a clear condition for use ('a reply to YOUR post') and a quota context (10 per day), which implies when the action is available. It does not name an alternative tool (e.g., vote or react) or state when NOT to use it, so it stops short of full routing guidance.

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