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

With no annotations present, the description carries the burden of disclosing behavioral traits. It meaningfully discloses partial-update semantics ('omitted fields remain unchanged') and mentions the is_active field for enable/disable. However, it does not mention permissions, reversibility, or side effects on ongoing deliveries, so disclosure is incomplete.

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 tightly structured: a one-line purpose, three concrete use-case bullets, and a key behavioral note. Every sentence earns its place, and the most important information is front-loaded.

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?

Given an output schema, 100% schema coverage, and 12 parameters, the description provides sufficient context: what it does, when to use it, and the crucial partial-update behavior. It could be more thorough by enumerating the categories of settings (auth, headers, delivery mode, etc.), but it is not incomplete enough for a 3.

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 schema covers all 12 parameters with descriptions, so the baseline is 3. The description adds no parameter-specific detail beyond schema, but it does reinforce the update behavior (only provided fields are updated), which is more behavioral than semantic. Therefore it stays at baseline.

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 'Update an existing webhook's configuration,' which clearly states the verb, resource, and scope. The 'Use when' bullets with concrete examples (URL, method, headers, is_active) further disambiguate it from sibling tools like create_webhook, get_webhook, and delete_webhook.

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 'Use when' section gives clear contexts: changing settings and enabling/disabling via is_active. It also communicates the partial-update constraint. However, it does not explicitly name alternatives or specify when not to use this tool, so it falls short of the explicit exclusion criteria needed for a 5.

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