verify_batch

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

Annotations only declare this is a non-read-only, non-idempotent, non-destructive open-world operation. The description adds the critical behavioral facts the annotations cannot convey: the call is asynchronous and returns immediately, the job runs in the background, status must be polled, and each address costs 1 credit.

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?

Five short sentences, front-loaded with the async submit semantics, then the workflow, then the cost, then the alternative routing. Nothing is redundant or padded.

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?

With no output schema, the description correctly explains the return (a batchId) and how to retrieve results later. Combined with the fully-documented parameter schema, an agent has everything required to call this correctly and complete the workflow.

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%, so name, emails, and webhookUrl are already documented in the schema. The description adds no format, ordering, or deduplication detail beyond the schema, so the baseline of 3 applies.

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 gives a specific verb and resource (submit email addresses for asynchronous bulk verification) plus the immediate return value (batchId). It explicitly distinguishes itself from the sibling verify_email, so the agent can tell the two apart 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?

It names the alternative for the single-address case ('Prefer verify_email for one-off checks') and lays out the exact follow-up sequence: poll get_batch_status until 'completed', then call get_batch_results. When-to-use, when-not-to-use, and next steps are all explicit.

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