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

Annotations already declare write, non-destructive, closed-world behavior, so the baseline is set. The description adds genuine behavioral context: the mention path 'rings their notification bell', which is a side effect an agent should know about, plus the thread-vs-reply branching. It stops short of noting auth requirements or idempotency.

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?

Three sentences, front-loaded with the core action and mode selection before the usage example. The closing etiquette line ('never mention someone who didn't ask') is editorializing but arguably still useful guardrail content.

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 write tool with no output schema and annotations covering safety, the description covers purpose, use case, thread/reply behavior, and mention side effects. Missing pieces are minor (approvalId meaning, mention limits, what a successful post returns).

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 only 43%, so the description is expected to compensate. It meaningfully explains mentionedUserIds (workspace member ids) and rootId (reply target), but leaves approvalId, workspace, entityKind semantics, and body constraints unexplained. Partial compensation warrants a baseline 3.

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+resource ('Posts a comment on a workspace entity') and clarifies the two modes — new thread vs reply when rootId is given. An agent can immediately tell what this does without opening the schema.

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 concrete use cases ('leave findings where the discussion already lives', 'a summary on a long thread') that establish when to reach for it. It does not, however, distinguish this from siblings comments_list or comments_resolve, nor state any when-not conditions.

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