Cancel a prepared eSIM quote

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

The description goes well beyond the annotations by disclosing the operation is purely local ('discards local information only'), never contacts the eSIM platform, and has no refund/charge implications. It also specifies the correct user-facing messaging, which is valuable behavioral context not present in the structured annotations.

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 well-structured with clear 'WHEN' and 'IMPORTANT' labels, each sentence earns its place, and it avoids redundancy. It is neither too terse nor overly verbose for the complexity of the operation.

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?

Combined with the schema and annotations, the description covers the action, scope, side effects, user communication, and parameter source. The presence of an output schema accounts for return-value details, making this description fully adequate for a single-parameter cancellation 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 input schema already fully documents the only parameter (quote_id: 'returned by prepare_purchase... Never invent, guess or edit one'), achieving 100% schema description coverage. The description adds no further parameter detail, so the baseline score of 3 applies.

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 uses a clear verb+resource ('Throw away a quote you prepared earlier') and explicitly differentiates from siblings like prepare_purchase and confirm_purchase by clarifying it only discards a local quote, not an order. The title 'Cancel a prepared eSIM quote' reinforces the 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 'WHEN' clause gives explicit usage context: 'the user says they do not want the plan you prepared, or wants to start again.' It also provides communication guidance ('never tell them an order was cancelled'). However, it does not explicitly name alternative tools or provide when-not conditions, so it stops short of a full 5.

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