Update Email

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the key precondition (only for unsent scheduled emails) but does not mention permissions, reversibility, or the error behavior if the email has already been sent. This is adequate but lacks depth for a mutation tool.

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?

Two concise sentences, front-loaded with the purpose and a usage constraint. No wasted words; 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?

The tool has only two parameters, a simple purpose, and no output schema. The description covers the essential purpose and the key limitation. It does not explain return values, but for a low-complexity mutation tool, the description is largely complete.

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?

Schema description coverage is 100%, with both 'id' and 'scheduledAt' already described in the schema. The description adds no additional meaning beyond reinforcing that the update involves the scheduled send time, so a 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 tool's function: "Reschedule a scheduled email by updating its scheduled send time." This specifies a concrete verb ('reschedule') and resource ('scheduled email'), distinguishing it from siblings like cancel-email or send-email.

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 provides a clear usage constraint: "Only works for emails that were scheduled and have not yet been sent." This tells the agent when the tool is applicable, though it does not explicitly name alternatives or exclusion scenarios beyond the unsent/scheduled condition.

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