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

With annotations declaring readOnlyHint=false, openWorldHint=true, and destructiveHint=false, the description usefully adds that comments are attributed to the caller and appear in the item's living thread — context beyond the structured fields. It stops short of noting permission requirements or editability of posted comments.

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 tight sentences with the action front-loaded and no filler; the parenthetical examples add information rather than padding.

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?

The existence of an output schema means return values need not be explained, and annotations carry the safety profile. However, with two of three parameters undocumented and no guidance on report_id/item_id linkage, the description is adequate but leaves clear gaps for a mutation tool.

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 only 33%: item_id and report_id have no descriptions at all. The description obliquely implies item_id via 'checklist item's thread' but says nothing about report_id or the relationship between the two identifiers, so it does not compensate for the coverage gap.

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 (Post a comment) and a specific resource (a diligence checklist item's thread), which cleanly distinguishes it from siblings such as add_diligence_citation, add_diligence_item, or update_diligence_item. An agent can identify the operation 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?

Provides illustrative content types (rationale for a pass/fail, a question, a finding), which implies when this tool is appropriate, but never states explicit conditions, prerequisites, or alternatives such as add_diligence_citation. Usage is inferable rather than stated.

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