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

With no annotations, the description carries the full burden and does so well: it discloses that the signing secret is returned only once and never shown again, that the caller's own session bearer is used, and that the webhooks:create scope is required. It does not cover failure modes or 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 short sentences, front-loaded with the action and followed by the two pieces of information an agent most needs (one-time secret, auth requirement). No filler.

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?

No output schema exists, yet the description explains the one non-obvious return element (the one-time secret field) and the authentication/scope prerequisites. For a three-parameter creation tool this is complete enough to call 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?

Schema description coverage is 100%, so url, events, and description are already documented in the schema; the description adds no syntax or format detail beyond it. The 'secret' mention is about the return value, not a parameter, so the baseline 3 applies.

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 and resource ('Create a webhook endpoint') plus its function ('receives job-completion notifications'). This clearly separates it from delete_webhook, get_webhook, list_webhooks, and update_webhook 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 described function implies when to use it (registering a new notification endpoint), but there is no explicit when-to-use guidance, no exclusions, and no routing to sibling tools such as update_webhook for modifying an existing endpoint. Adequate but leaves selection to inference.

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