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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false, so the safety profile is covered. The description adds useful behavior (automatic @mention parsing, root-anchored replies) but says nothing about what the required idempotency_key does or what a replayed request returns — notable given the idempotentHint=false annotation.

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 short, front-loaded sentences with no filler; the purpose comes first, then the required field, then the reply rule. 'Text body is required' mildly restates the schema's required list but earns its place as emphasis for a mutation.

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 an 8-parameter mutation with no output schema, the description covers the core call pattern but omits how the required idempotency_key should be formed and whether workspace_id is mandatory for comment creation (the schema says it's required when creating content). Those are material 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 coverage is 63% and the description clarifies the two hardest parameters: it confirms `text` is required and sharpens `parent_comment_id` into 'pointing to the root comment,' implying flat threading. It leaves `idempotency_key`, `brand_id`, and `id` unexplained, so it only partly compensates 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 and resource: 'Create a comment on a post.' An agent immediately knows the operation. It does not, however, name or contrast with the evident siblings update_post_comment, delete_post_comment, or list_post_comments, so differentiation is left to the tool name.

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 gives one concrete usage rule — replies must set parent_comment_id to the root comment — which is real guidance about when/how to use the tool. There is no explicit when-not-to-use clause and no pointer to the sibling comment tools for reading, editing, or deleting.

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