reserve_item

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

The description explicitly states that this writes to the database (non-read-only) and that it fails on insufficient stock, aligning with the annotations. It also hints at idempotency through the idempotency_key, but does not fully detail all side effects or error handling.

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 brief and to the point, consisting of three short sentences. No extraneous information or repetition is present, making it efficient and easy to parse.

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?

The description covers the core functionality and failure condition, but it does not mention expected return values or output format, nor does it explain the reservation lifecycle or how it relates to release_reservation. Some context is missing for full autonomous use.

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?

The schema covers 60% of parameters with descriptions, but sku and customer lack any description, and quantity/ttl_minutes only have default values. The tool description does not clarify the meaning or format of these parameters, leaving ambiguity for the agent.

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 the action (hold/reserve), the resource (SKU units), the condition (fails if insufficient stock), and a note to confirm with the salesperson. It is specific and unambiguous about the tool's primary purpose.

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 provides a usage hint ('confirm with the salesperson first') and implies a precondition (check stock), but it does not explicitly compare with alternative tools or specify when not to use this tool. The guidance is present but not fully explicit.

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