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. It discloses the core mutation (setting a new send time) and implies a PATCH operation, but it does not mention prerequisites (e.g., the email must still be scheduled), reversibility, or any side effects. This is minimal but not misleading.

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 a single, front-loaded sentence with zero filler. It states the action, the target, and the HTTP method efficiently, making it easy to scan.

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 two-parameter mutation with no output schema, the description covers the essential call requirements. It does not mention edge cases (e.g., what happens if the email is already sent), but for a straightforward PATCH it is largely sufficient. A slightly more explicit note about preconditions would make it a 5.

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 both parameters fully (id and scheduled_at with its format). The description adds no additional semantics beyond restating that scheduled_at sets the new send time. With 100% schema coverage, the 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 states a specific verb ('Reschedule') and resource ('a scheduled email'), plus the HTTP method (PATCH). This clearly distinguishes it from siblings like cancel_email (which cancels) and send_email (which sends a new email). An agent can immediately understand the tool's role.

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 clearly implies the use case: changing the send time of an already scheduled email. It does not explicitly exclude other scenarios or name alternatives like cancel_email, but the context is unambiguous. It lacks explicit 'when not to use' guidance, so it falls short of a 5.

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