postgrid_cancel_letter

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

With no annotations present, the description carries the behavioral disclosure burden. It does disclose the critical precondition and timing constraint, which is valuable. However, it does not mention whether cancellation is irreversible, what happens if invoked on a non-ready letter, or any side effects beyond the cancellation itself.

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 short sentences with no filler. The primary action is front-loaded, and the important status condition is stated immediately after. Every word earns its place.

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 low-complexity tool with one fully documented parameter, the description provides the essential invocation detail: the ID and the status precondition. It does not describe the return value or error behavior, but those are less critical for selecting and invoking this simple cancel 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?

The input schema has 100% description coverage: the single required parameter 'id' is described as 'Letter ID to cancel.' The tool description does not add meaning beyond the schema, so the baseline score 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 uses a specific verb and resource: 'Cancel a letter.' It also includes a meaningful precondition about status, which makes the tool's purpose unmistakable. Among the sibling tools, none handles letter cancellation, so it is naturally differentiated.

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 explicitly says when the tool works: only when the letter status is 'ready' and before printing begins. This gives an agent a clear eligibility condition, though it does not name alternative tools or explicitly state what to do when the status is not ready.

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