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

Annotations already declare mutating-but-non-destructive, idempotent behavior; the description adds the rate-limit consequence of wrong codes and the alternative confirmation path via the email link. That rate-limit disclosure is real behavioral value not present in structured fields.

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?

Three tight sentences: purpose first, then the hard usage constraint, then the failure fallback. The explanatory clause about avoiding the email link earns its place by motivating the tool.

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 two-parameter, fully documented input with annotations and no output schema, this covers purpose, constraints, and failure behavior. Only the post-success state (reminders now active) could be slightly more explicit.

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?

With 100% schema coverage, the schema already explains both parameters in detail. The description adds only a modest clarification that the email must be the one the reminder was created with, so baseline 3 holds.

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 and resource: switching on beep.me email reminders by submitting a 6-digit confirmation code. The mechanism is distinctive enough that an agent can tell it apart from remind_me or my_reminders, though no sibling is named explicitly.

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 gives clear conditions for use (a code the user typed themselves, the address the reminder was created with) plus firm prohibitions against guessing or reusing codes, and a fallback (the email link still works). It lacks explicit routing against sibling tools such as remind_me.

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