create_webhook_endpoint

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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent write. The description adds genuinely valuable context beyond that: the signing secret is returned exactly once, is not retrievable later, and must be surfaced to the user once and not repeated. The one-time-secret behavior corroborates idempotentHint=false and is the kind of detail annotations cannot carry.

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?

Three short, front-loaded lines with the operation first and the constraint second — efficient. Minor waste: the first line's parenthetical about the signing secret duplicates both the title and the second sentence.

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 fills the gap by disclosing that the response contains a one-time secret and how to handle it. Required params and the auth scope are stated. The remaining gap is that the `events` selection — the core decision when creating a webhook — is left entirely to the bare enum.

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 33% — `events` and `description` carry no descriptions. The tool description adds nothing about either parameter: no note that `events` accepts a specific enum set and requires at least one unique value, and no meaning for `description` (label? internal note?). With coverage this low, the description needed to compensate and does not.

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 opens with a specific verb+resource ("Add a webhook endpoint"), which cleanly separates it from update/delete/list/rotate/test siblings whose names appear in the tool list. It stops short of explicitly naming those alternatives, but the operation is unambiguous.

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 states the required scope `webhooks:write`, which is a useful prerequisite, but gives no when-to-use vs. when-not guidance. It never clarifies the relationship to `rotate_webhook_secret` (for an existing endpoint) or to `update_webhook_endpoint`, so the agent must infer where this fits.

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