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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, and the description's 'creates a new comment' is consistent with that write profile. It adds the nesting behavior but says nothing about whether the reply is auto-approved or held for moderation, nor about permission requirements for a non-destructive write.

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 short sentences with the action front-loaded and no filler. The second sentence restates much of the first ('creates a new comment as a reply'), making it mildly redundant rather than wasteful.

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 four-parameter creation tool with full schema coverage and annotations covering the safety profile, the description is sufficient to call it correctly. It omits the post-mutation reality an agent may care about, namely whether the reply publishes immediately or enters moderation.

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% and every parameter (post, parent, content, site_id) is documented in the schema itself, so the schema does the heavy lifting. The description adds no format or constraint detail beyond that, which is the expected baseline when coverage is complete.

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 (reply) and resource (WordPress comment) and clarifies that it creates a new comment nested under an existing one. It does not distinguish itself from related siblings like wp_moderate_comment or wp_list_comments, so the agent must infer the boundary from the name alone.

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 gives no when-to-use or when-not-to-use guidance and never names an alternative tool. It implies a prerequisite (an existing parent comment) but does not state what happens if the parent is invalid or how this differs from creating a top-level comment.

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