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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It reveals idempotency and the header requirement, but does not clarify whether the send is synchronous or async (only 'Queue' hints at it), what the response returns, or how errors are handled. It references the canonical route's behavior but does not spell out the response shape. This is adequate but leaves meaningful gaps.

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?

The description is short and mostly front-loaded with the purpose, but the final sentence 'Prefer the canonical route' is cryptic and could mislead the agent. The first two sentences are efficient, but the ambiguous closing sentence detracts from conciseness and clarity. It could be tightened by removing or clarifying that instruction.

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?

Given the complexity (8 parameters, nested object, no output schema), the description provides core facts (idempotency, header requirement, matching behavior to the API) but does not explain what a successful call returns (e.g., a queued message ID), how the queue behaves (e.g., async delivery), or failure semantics. These are important for an agent to use the tool confidently, and the description leaves them to inference from the schema or prior knowledge of the API.

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%, so the schema already documents each parameter. The description adds value by clarifying that X-Organization-Id is 'still required with the session and must match the path'—a constraint not evident from the schema, which simply lists organization_id. This extra context about the header–path relationship helps the agent set up the call correctly.

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 states a specific verb ('Queue') and a clear resource ('one idempotent transactional delivery'), and further distinguishes it by referencing the canonical POST /api/messages behavior. It is immediately clear that this tool sends a transactional message with idempotency, and it stands apart from the many other commsharbor tools in the sibling list.

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 implies usage for transactional delivery and notes a prerequisite (X-Organization-Id header must match the path). However, it does not explicitly state when to use this tool versus any alternative, and the sentence 'Prefer the canonical route' is ambiguous—it could mean prefer this tool or prefer the REST API. No exclusions or sibling comparisons are provided.

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