Create Mail Webhook

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says 'Create a webhook', which implies mutation, but it doesn't disclose side effects such as whether the URL is validated, whether duplicate webhooks are allowed, or what the response contains. This minimal disclosure is inadequate for a mutating operation with zero annotation coverage.

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 a single, concise sentence that is front-loaded with the key action and resource. It has no fluff or redundant wording. However, it is so brief that it omits useful details, which slightly detracts from its structural effectiveness.

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?

The tool has no output schema and the description does not explain the return value or the expected response. It also lacks context about event types, URL constraints, or how this fits into the webhook management workflow. Given the rich set of sibling webhook tools, this description leaves important gaps for an agent to use it correctly.

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?

The input schema provides 100% description coverage for all three parameters (url, event, mailbox_id). The description adds no additional meaning beyond the schema, so a baseline score of 3 is appropriate. It doesn't compensate for missing information like allowed event values or URL formats.

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 clearly states the action ('Create') and resource ('webhook for a mailbox'), which distinguishes it from sibling webhook tools like mail_webhooks_get, update, and delete. It is direct and unambiguous, though it doesn't add extra context about the mailbox scope beyond what the schema provides.

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 provides no guidance on when to use this tool versus alternatives. It does not mention prerequisites, such as requiring an existing mailbox, or conditions that would make this tool preferable to updating or testing a webhook. There is no contextual information about the webhook lifecycle.

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