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

Annotations already declare readOnlyHint=false, destructiveHint=true, and idempotentHint=true, so the safety profile is covered. The description adds genuine context beyond that: replies land on the conversation's own channels (chat, email, WhatsApp, Messenger), app-store review replies are public, and it returns the conversation id and send time. The one gap is that it never explains why the operation is marked destructive/irreversible.

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 compact sentences, front-loaded with the usage condition and followed by output and scope exclusions. Every clause earns its place with 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?

With annotations covering safety, an output schema covering return values, and 100% schema description coverage, the description supplies the remaining operational context: approval precondition, delivery channels, and public-visibility caveat. It is essentially complete, though it could note the idempotency retry contract explicitly rather than relying on the schema.

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 the schema already documents content (with its 4,000-character cap), conversationId, and idempotencyKey ('reuse it only to retry the same send'). The description's phrase 'exact reply' reinforces content semantics but adds no new parameter-level meaning, so the baseline of 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?

The description gives a specific verb and resource ('send an exact reply to a customer in one Supovia conversation') and immediately distinguishes itself from siblings like resolve_conversation by stating it is 'Not for internal notes or closing the conversation.' An agent can tell exactly what this tool does 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?

It states the triggering condition explicitly ('when the user approves an exact reply'), names the excluded actions (internal notes, closing the conversation), and the context signals inside it ('approves an exact reply') route the agent to this tool rather than the other conversation siblings.

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