verify_email_risk

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

With no annotations, the description carries the full disclosure burden. It usefully tells the agent this is an instant, single-call evaluation returning a fraud score plus two boolean-style signals, but it omits permission/auth requirements, behavior on malformed or unknown addresses, rate limits, and whether results are cached or live. Adequate but not rich for a zero-annotation 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 tightly written sentences with the outcome types front-loaded. 'Powered by FraudShield' is marketing filler that adds no invocation value, but it costs only four words.

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 one-parameter, no-annotation, no-output-schema tool, the description covers what signals come back but not their shape, range, or interpretation (e.g. score scale). An agent can call it correctly but cannot interpret the response without experimentation.

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%: the single 'email' parameter is fully documented in the schema, including an example. The description adds no format or syntax guidance beyond that, so the schema does the heavy lifting and a baseline 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 names a concrete resource (email address) and enumerates what the tool returns: fraud score, disposable/temporary mailbox detection, and deliverability risk. That is clear and specific. However, it does not differentiate itself from the sibling email_deliverability_audit, which covers overlapping deliverability territory, so the agent cannot tell the two apart from the text alone.

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 statement of when to use this tool versus the sibling email_deliverability_audit, no prerequisites, and no mention of when it should not be used. The agent must infer that this is a single-value risk lookup based on the name and enum-free single parameter.

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