get_label

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

No annotations are provided, so the description must carry the burden. It reveals that the output is base64-encoded PDF, which is helpful. However, it does not mention any side effects, authentication needs, or whether it is a read-only operation (likely read-only but not explicit).

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 two sentences, front-loads the core purpose, and includes a key detail about the return format. No extraneous information.

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 retrieval tool with one parameter and no output schema, the description covers the essential purpose and output format. It could mention that the label is for printing or include a link to orderIdentifier documentation, but overall it is complete enough.

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 already describes the single parameter with high coverage (100%), and the description mentions it ('orderIdentifier returned when booking the order'). This adds context by linking the parameter to a previous step, which is useful but not transformative given schema coverage.

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'), the resource ('shipping label'), and the context ('Royal Mail Click & Drop order'). It also specifies the return format ('base64-encoded PDF label'), which adds precision. This distinguishes it from siblings like book_order or cancel_order.

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 the tool is for retrieving a label after booking, but does not explicitly state when to use it versus alternatives. It mentions the input parameter ('orderIdentifier') but does not provide guidance on prerequisites or conditions for use.

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