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

Annotations already declare destructiveHint=true and openWorldHint=true, but the description adds material context the annotations cannot: the reply is publicly visible on the listing, the confirm flag produces a no-op preview rather than sending, and a separate manage:inbox permission is required. This is exactly the kind of disclosure that prevents an accidental public post.

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 tight sentences, front-loaded with the core action and the public-visibility warning before the confirm semantics and permission note. No filler.

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 non-idempotent, public-facing mutation with no output schema, the description covers the safety profile (preview gating), the visibility consequence, and the permission prerequisite. Nothing an agent needs to call it correctly is missing.

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 100%, so reviewId, accountId, message, and confirm are all documented in the schema. The description reinforces the confirm preview semantics and the source of the IDs, but adds little syntax or meaning beyond what the schema already provides, so the baseline 3 applies.

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 ('Reply to a review of your business') and explicitly distinguishes itself from the sibling direct-message reply tool ('UNLIKE a direct-message reply, a review reply IS PUBLIC'). An agent can immediately tell which sibling to pick without opening either 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 explicit when-to-use guidance on the confirm flag ('Pass confirm: true only after the owner approved the exact text; without it, this returns a preview and sends nothing at all'), and contrasts this tool against the direct-message alternative. Both the trigger condition and the safe default are spelled out.

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