update_inventory_item

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

Beyond annotations (idempotentHint=true), description adds crucial behavioral details: partial update nature, 404 for non-owners without leaking existence, and idempotency confirmation.

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 concise sentences with clear front-loading: first sentence defines the action, second confirms idempotency, third adds ownership context and links to alternative tools. No superfluous text.

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 complexity (16 parameters, no output schema), the description covers key aspects (partial update, idempotency, ownership, lifecycle alternatives). Lacks return value description but is otherwise adequate for a patch operation.

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 0%, and the description does not explain individual parameters (e.g., name, quantity). It only implies partial update but fails to add semantic meaning for the many optional fields.

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 clearly states it patches an inventory item with 'only provided fields change', which is specific and distinguishes from sibling tools like 'mark_for_sale' and 'mark_sold' that handle lifecycle changes.

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 mentions ownership requirement ('Caller must own the item') and provides alternatives ('see `mark_for_sale` and `mark_sold` for ergonomic wrappers'), guiding when to use this tool versus siblings.

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