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

With no annotations, the description must carry the behavioral burden, and it does disclose the code format (6 digits), the delivery channel (email), and the destination (the account's address). It omits rate limits, auth requirements, and whether a fresh code invalidates the previous one, so the disclosure is partial.

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?

A single front-loaded sentence with no filler; every word (fresh, 6-digit, account's address) adds precision.

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 zero-parameter, no-output-schema action the description is nearly sufficient: the agent knows exactly what will happen. It only lacks usage context (when to trigger it) and any note on side effects or throttling.

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 tool takes zero parameters, so per the rubric the baseline is 4. The description correctly reflects this by identifying the target (the account's address) rather than any caller-supplied argument.

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 (email/resend), resource (6-digit verification code), and destination (account's address), which is far more concrete than the title alone. However, it does not distinguish itself from siblings like verify_account or sign_up, leaving the agent to infer the relationship.

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?

There is no explicit when-to-use guidance, no prerequisites (e.g., must be signed in, code previously sent), and no mention of alternatives such as verify_account. The word 'resend' implies a prior send failed or was not received, but this is left to inference.

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