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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=false), and the description adds genuinely non-redundant context: the required scope, the accepted entry statuses, and the resulting 'confirmed' state. It stops short of describing failure behavior, whether confirmation is reversible, or what happens to a previously confirmed value.

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 with zero filler; the core action is front-loaded and the preconditions and permission follow in priority order. Every clause carries information an agent needs.

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?

No output schema exists and the tool takes a nested object, so the description carries real weight — and it does supply the state machine, scope requirement, and units. Only the undocumented notes parameter and post-call/failure semantics remain unaddressed.

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 50%: id and idempotency_key are documented in the schema, while notes and the nested dimensions_cm fields are not. The description compensates for the unit ambiguity by stating '(cm)', which the schema omits, but says nothing about notes or how the three dimensions are interpreted.

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 and resource ('Confirm the item's real-world dimensions (cm)') and immediately pins down the state transition it performs ('Moves the item to confirmed'). That is distinguishable from siblings like updateItem, startGeneration, or publishItem without opening any schema.

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?

Explicitly names the precondition states ('awaiting_confirmation', or 'failed' with a completed analysis), the ordering constraint ('before generation'), and the required permission ('scope: confirm_scale'). This is a full when-to-use/when-not-to-use statement rather than implied guidance.

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