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

Annotations already declare a non-read-only, non-idempotent, open-world creation operation, so the safety profile is covered. The description usefully adds that events are drawn from the entire account rather than one event type, but says nothing about delivery behavior, retries, secret-based signing (which lives in the schema), or what is returned on creation.

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?

A single lean sentence with the account-scope qualifier placed early; there is no filler or redundancy.

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 5-parameter, 3-required creation tool with no output schema and thin schema descriptions, the definition omits too much: trigger selection, required vs optional fields, and what the caller receives back. An agent could not reliably populate the parameters from this description alone.

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 only 20% — just the 'secret' field is documented. The description does not explain subscriberUrl, the required trigger enum, active toggling, or payloadTemplate, so it fails to compensate for the coverage gap on a 5-parameter tool.

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 conveys the action (register a delivery target) and the resource (booking events) and scopes it to 'the whole account', which implicitly distinguishes it from the event-type-scoped sibling create_event_type_webhook. It never uses the word 'create' and the reader must infer that a webhook object is being registered, so it stops short of 5.

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 explicit guidance on when to use this instead of create_event_type_webhook, update_webhook, or test_webhook. No prerequisites are stated, such as required scopes or the fact that at least one trigger must be supplied.

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