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

With no annotations, the description carries the behavioral disclosure burden, and it does a solid job: it discloses that the API refuses deletion once history exists and that D numbers are never reissued. It does not mention permissions or whether the deletion is reversible beyond the D-number statement, but the core refusal and numbering behavior are clearly exposed.

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 compact and front-loaded: the core action and condition appear in the first sentence, and the follow-up rule is one short sentence. The phrase 'naming when' is slightly awkward and could be misread, but it does not create significant bulk or confusion.

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 mutation tool with no annotations and no output schema, the description covers the essential invocation context: what may be deleted, what will be refused, and what to do instead. It does not describe success/error responses, but the refusal behavior and numbering policy give an agent enough guidance to call it correctly.

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 parameters are already fully documented in the input schema. The description adds preconditions and consequences rather than new parameter-level meaning, so the baseline of 3 is appropriate.

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 uses a specific verb and resource: 'Delete one deliverable still planned with no history.' It clearly delimits scope by excluding started, delivered, or accepted deliverables, so an agent can distinguish it from siblings like deliverable_add and deliverable_status.

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 an explicit when-not-to-use condition: a deliverable started, delivered, or accepted is refused. It also names the alternative action: 'add a corrected deliverable instead,' which maps directly to the sibling deliverable_add. This leaves no ambiguity about which tool to choose.

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