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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is largely covered. The description adds genuinely useful behavior not in the annotations: the response includes each webhook's secret and its disabled/stopped-after-failure status, and the call also returns a catalogue of every event a webhook can send. It does not mention pagination, ordering, or how many webhooks are returned at once.

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?

It is short, but the first sentence is a fragment with no verb and the second is a long dash-separated clause that appends the event catalogue awkwardly to the webhook fields. Nothing is padded, but the structure is not front-loaded with a clear action statement.

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 one-parameter read tool with no output schema, the description carries the burden of explaining the return value, and it does so by enumerating the returned fields and noting the secondary event list. Missing details are minor: volume, ordering, and whether the secret is always returned or masked.

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?

With a single parameter at 100% schema description coverage, the schema already explains that 'site' is 'The site to work on, as list_sites names it'. The description only restates this ('On one site of the account, named in site') without adding formatting, lookup, or failure-mode detail, so the baseline of 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?

The description never uses a verb like 'list' or 'retrieve'; it is a nominal fragment ('On one site of the account, named in site. Every webhook — its name, the one event it sends, its URL...'). The resource and scope are identifiable, and the enumeration of returned fields implies a read/list operation, but it does not explicitly distinguish itself from siblings such as create_webhook, update_webhook, or test_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?

There is no when-to-use guidance and no mention of alternatives. The agent must infer that this is the read path for webhooks rather than delete_webhook, update_webhook, or test_webhook, and there are no stated prerequisites, such as a required permission level to view signing secrets.

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