Parcel details

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

The readOnlyHint annotation already declares the safe read-only nature. The description adds behavioral context by disclosing the kind of data returned (status, locker, pickup code, QR payload) and the flexibility of accepting a unique short prefix. This goes beyond the annotation without contradicting it.

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 a single sentence that front-loads the core purpose, then efficiently lists the returned details. Every part adds value, with no repetition or filler.

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 simple getter with 2 parameters, no output schema, and read-only annotations, the description is adequate. It covers the main purpose and key return fields. It doesn't mention error handling or exact response structure, but those are not essential for a straightforward retrieval tool.

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 coverage is 100%, with descriptions for both parameters. The tool description mentions the prefix flexibility for shipmentNumber, which is already partially in the schema ('Full shipment number or unique prefix'). It adds no significant extra parameter semantics, so the baseline of 3 is appropriate.

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: 'Get details for one parcel by shipment number'. It specifies the resource (parcel) and the identifying key (shipment number or unique short prefix), and lists the returned fields (status, locker, pickup code, QR payload). This distinguishes it from sibling tools like list_parcels or track.

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 implies usage context: it is for a single parcel specified by shipment number, as opposed to listing all parcels or tracking. However, it does not explicitly mention when not to use it or compare with alternatives, so it earns a 4 rather than a 5.

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