Cancel Email

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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses the mutation and the 3-minute scheduling constraint, but it omits auth requirements, irreversibility/idempotency, and what happens to pending emails.

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?

It is two sentences with no waste: the first states the action, and the second front-loads the key scheduling restriction. Every sentence 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 simple one-parameter mutation, the description gives the key timing restriction needed for correct invocation. However, with no annotations and no output schema, it does not explain result behavior or irreversibility, leaving a meaningful completeness gap.

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 has 100% description coverage for the single required parameter, including the email ID format (em_xxx). The description adds no parameter-level detail beyond what the schema already documents, so the baseline 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 gives a specific verb and resource: 'Cancel a scheduled or pending email.' This clearly distinguishes the action from siblings such as send-email, update-email, and retry-email without requiring the agent to inspect schemas.

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?

It states a concrete when-allowed condition for scheduled emails: cancellation requires the scheduled time to be at least 3 minutes in the future. It does not, however, name alternatives or explain when to prefer another tool such as update-email.

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