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

With only destructiveHint available in annotations, the description carries most of the burden and delivers: it names the required permission (COMMENTS_WRITE), the underlying GraphQL mutation and its union return type, and the mutation nature of the call. It does not explain reversibility or the union member semantics, keeping it just short of the top score.

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?

Front-loads the critical 'MUTATES' warning and required-parameter list, and is dense without padding. Slightly terse packing of permission and GraphQL details into one line, but nothing is wasted.

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 mutation with no output schema, the description supplies permission requirements, the operation name, and the return type, plus required/optional parameter roles. Return-value structure is only gestured at ('→ union') rather than described, leaving a minor gap.

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 baseline is 3; the description adds some meaning ('stringified TipTap/ProseMirror JSON document', threadParentId used 'to reply'). However it mislabels threadSortOrder as Required when the schema marks only content and discussionId as required, a discrepancy that could push agents to always supply it.

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 and resource ('add a comment to a meeting discussion thread') and immediately flags the write nature of the operation. No sibling tool performs comment creation, and the meeting-thread scope is unambiguous.

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?

The description clarifies the reply case ('threadParentId (to reply)') and the reply-vs-new-comment distinction, which is useful implied usage. However, it gives no explicit when-to-use/when-not guidance or alternatives, so this is adequate but with a clear gap.

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