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

Annotations only declare destructiveHint=true; the description goes further by disclosing the side effects (inventory allocation, creation of both a planning and a line) and the default merge behavior. It omits any statement about shortage/error handling, permissions, or what is returned.

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 tight sentences, front-loaded with purpose and effect before the default-behavior note. The trailing REST endpoint reference is mildly redundant for an agent but harmless and short enough to keep the response efficient.

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 6-parameter mutation tool with full schema coverage and no output schema, the description covers the operation's core behavior adequately. It does not describe the return payload (created planning/line identifiers) or failure modes, which leaves a small gap an agent would otherwise want filled.

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 both the mode enum semantics and confirm_shortage are already fully documented in the schema. The description restates the default mode behavior but adds no syntax or meaning beyond what the schema provides, matching the baseline of 3.

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?

States a specific verb (add/book) and resource (a quantity of a product to an order) plus the concrete effect (creates a planning and a line). This is clearly distinguishable from siblings like create_order or list_plannings.

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 explains the default behavior (reuse an existing planning for the same product) and the schema enumerates modes, which implies when each mode applies, but there is no explicit guidance on when to call this tool versus create_order, update_order, or other siblings.

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