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

With no annotations, the description carries the full burden and does disclose real behavior: partial-update/merge semantics ('Unset fields keep their current value'), authentication via the caller's own session bearer, and the required webhooks:update scope. It omits what happens on invalid event strings, idempotency, and any rate limits, keeping it short of a 5.

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 tight sentences, front-loaded with the action and fields before the merge semantics and auth requirements. No redundant or filler content; every sentence adds information an agent would otherwise have to guess.

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 mutation tool with no annotations and no output schema, the description covers the field set, merge behavior, and auth/scope requirements, which is enough to invoke it correctly. It stops short of describing the response body, which the absence of an output schema leaves undocumented.

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 the schema already documents each parameter and the 'omit to keep current value' semantics. The description adds the status values (active/paused), which the schema does not enumerate, but otherwise restates the field list rather than adding syntax or validation detail.

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?

States a specific verb (update) and resource (webhook endpoint) plus the exact mutable fields and the status enum values. The verb choice cleanly separates it from the create_webhook, delete_webhook, and get_webhook siblings without needing their schemas.

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 update verb and the note that unset fields keep their current value imply the use case is modifying an existing webhook, and implicitly exclude create/delete. However, there is no explicit when-to-use statement, no prerequisite that the webhook must already exist, and no routing guidance toward alternatives.

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