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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the description earns credit by adding what annotations cannot: the call is synchronous and reports the HTTP status, and it surfaces the receiver's error on non-2xx responses. That error-propagation behavior is the key operational fact for an agent.

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?

Two tight sentences, zero filler, with the core action front-loaded and the failure behavior as a follow-up. Nothing is wasted.

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 usefully covers both the return value (HTTP status) and error semantics for a simple 3-parameter tool. The remaining gap is per-parameter detail on event and webhookId, which is minor relative to overall completeness.

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% — site is documented in the schema, while event (an enum) and webhookId have no descriptions. The description alludes to 'one event' and 'the webhook URL' but adds no format, default, or optionality guidance, so it fails to compensate for the coverage gap.

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 — delivers a sample payload for one event to the webhook URL — which an agent can distinguish from create_webhook, update_webhook, retry_webhook_delivery, and get_webhook_history. It does not explicitly name those siblings, but the 'test' framing 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?

Use case is implied (verifying a webhook's endpoint responds) but the description never states when to use this versus retry_webhook_delivery or get_webhook_history, nor any precondition such as the webhook needing to exist first.

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