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

With annotations carrying only generic false hints, the description supplies meaningful behavioral detail: the operation returns counts, refuses due dates before the reference document's date, and starts the deliverable as 'planned'. It does not disclose every side effect, but it covers the main behavioral traits an agent needs.

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 short sentences, each earning its place: the first states the action and return value, the second clarifies a critical monetary unit, and the third warns about a validation rule and initial status. The most important information is front-loaded.

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 7-parameter creation tool with no output schema, the description gives the key context: return values, unit semantics, a validation constraint, and initial state. The schema covers the remaining parameter details, so nothing critical is missing for invoking 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 86%, so the schema already documents nearly all parameters well. The description reinforces value_minor semantics ('NET of VAT in whole MINOR units') and the due-date constraint, but adds little beyond the schema; it earns the baseline for high schema coverage.

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 specific verb ('Add'), a specific resource ('one dated deliverable'), and a concrete outcome ('return its D number and the new counts'). It is clearly distinct from the sibling tools, which delete, get, list, or change 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 establishes clear usage context: it is for creating one dated deliverable, while siblings handle deletion, status, and schedule-level operations. It does not explicitly state exclusions or alternatives, but the action and resource are unambiguous among the sibling set.

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