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

Annotations already establish that this is a non-destructive, idempotent, read-only operation, so the bar is lower. The description adds meaningful behavioral context beyond annotations: results are retained for 90 days, no verification is started, no following page is fetched automatically, and pending responses should be handled by checking the task later.

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?

The description is front-loaded and compact. Each sentence adds operational value: pagination scope, retention, non-start behavior, state filtering guidance, and pending response handling.

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?

There is no output schema and no parameter descriptions, so the description must do more work. It covers return cursor behavior and important operational details, but it omits the meaning of the required id parameter and does not fully explain how to use the input cursor.

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 0%, so the description must carry parameter meaning. It explains state filtering semantics well, but it does not explain the required id parameter or clarify that the cursor parameter is used to fetch the next page, leaving two of three parameters undocumented.

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 and resource: read up to 100 existing email results plus a next-page cursor. It is clear what the tool returns, but it does not explicitly contrast itself with sibling tools such as bounceban_bulk_status or bounceban_verify_email.

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 gives useful usage guidance: omit state to get all processed results while a task is running, filter by state with the caveat that in-progress results may be omitted, and treat a pending response by waiting and checking the existing task later. It does not explicitly route the agent to an alternative sibling tool, but the when-to-use context is strong.

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