Acknowledge mailbox message

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

Annotations already signal mutation (readOnlyHint=false), idempotency, and non-destructiveness. The description adds value by disclosing the active-claim ownership requirement and the expected timing. No contradiction, though the exact effect of acknowledgement on mailbox state is not spelled out.

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 concise sentences with no filler: the first gives the action and timing, the second adds the single gating condition. It does not repeat schema fields or annotation data.

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 simple two-parameter tool with an output schema and full annotations, the description covers when to call and who is allowed to call. The output schema handles return-value details, so nothing essential is missing for correct invocation.

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%, with message_id format/length and response_format enum/default already documented. The description adds no parameter-specific meaning, so the schema appropriately carries the burden.

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 names a concrete action ('acknowledge') and a specific resource ('claimed mailbox message'), with 'after successful processing' establishing intent. 'Acknowledge' clearly contrasts with sibling claim_message and read-oriented tools like get_message and list_unread, so an agent can distinguish it.

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 states the lifecycle condition—use after successful processing—and the ownership prerequisite: only the API key that owns the active claim can acknowledge. It does not enumerate all sibling alternatives, but the claim-then-acknowledge sequencing is unambiguous.

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