Verify email addresses

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

Annotations cover safety hints, but the description adds information they do not carry: the credit cost per address and the fact that find_emails output is already verified, which prevents redundant spend. It stops short of describing what the verification result looks like (status values, per-address outcome), leaving a modest gap.

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 sentences, no filler, with the purpose front-loaded and the cost/alternative caveat immediately after. Every clause earns its place.

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?

Covers cost, eligibility, and avoidance of redundant calls for a paid, non-idempotent operation, and annotations carry the safety profile. With no output schema, it could still say what a verify call returns, but for a one-parameter tool this is close to sufficient.

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% and the single emails parameter is fully documented with min/max items and format, so the baseline is 3. The description's 'one credit per address' is a billing note rather than added parameter syntax or semantics.

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 and resource ('Check whether email addresses are deliverable') and explicitly frames the outcome (before sending to them). It also names the sibling tool scrupp_find_emails and explains the distinction, so an agent can route without opening either schema.

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?

Gives explicit when-to-use ('addresses you already have') and when-not ('not on ones scrupp_find_emails just returned'), with the reason (those are verified already). This is exactly the alternative-routing guidance the dimension rewards.

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