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

Annotations already declare the mutation profile (readOnlyHint false, idempotent true, destructive false), so the bar is lower, and the description still adds real state-transition context: closing demands an outcome and reopening clears the stored outcome. It stops short of noting permission requirements or what the response contains.

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?

A single sentence that front-loads the primary operation and compresses the three modes without filler. Nothing in it is redundant with a weaker element.

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?

With annotations and an output schema carrying the safety and return-value burden, the description covers all three behaviors an agent needs to select the tool. The only looseness is the mention of 'a branch,' which has no corresponding parameter in the schema.

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 the baseline is 3. The description restates the outcome/resolved mechanics that the schema already documents in detail, adding no syntax, format, or constraint information the schema lacks.

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 gives specific verbs (close, change, reopen) against a clearly identified resource (a topic or branch) and the decision/outcome attached to it, which separates it from list_discussion_posts or create_discussion_post. It never names a sibling explicitly, so it falls short of the top score.

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 enumerates the three legitimate modes (close with a decision, replace a decision, reopen), which implies when to reach for it. It does not say what to use instead for editing topic content or posting, and no prerequisites or exclusions are stated.

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