mailveri_verify_email

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

With no annotations, the description carries the full burden and delivers substantial behavioral detail: a complete enum of return values, the credit-balance side effect, and an explicit rate limit of 1 request per second. It doesn't cover failure modes like retry behavior or what happens when credits are exhausted, but for a read-only verification call this is strong disclosure.

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?

Front-loaded with the core action, followed by a clean bulleted enumeration of statuses and two practical notes (credit balance, rate limit). Every section earns its place; formatting is easy to scan. Slightly verbose in the status list but each entry is informative.

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?

An output schema exists, so the description needn't explain return values, yet it helpfully enumerates status meanings beyond raw field names. Combined with the rate limit and credit-balance note, it covers what an agent needs to call the tool correctly and interpret its response. Absence of pagination or error-handling notes is minor for a single-record verification.

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?

Only 1 parameter and schema description coverage is 0%, meaning the schema adds no meaning to 'email'. The description compensates by clarifying this is a single email address and by enumerating the semantic categories the email will be classified into, which helps the agent understand what the input maps to. With 0 params the baseline would be 4, and this meets that bar.

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?

States a specific verb+resource ('Verify a single email address') and clearly marks its scope as single vs. the sibling mailveri_verify_batch. The output value enumeration further disambiguates its purpose.

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 implies usage via 'single email address,' which naturally contrasts with mailveri_verify_batch, but it never explicitly states when to prefer this tool over the batch alternative or any prerequisites. Usage context is present but only implied.

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