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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, and the description's 'Read-only' merely restates that. It does add useful context by naming the fields the response contains (URL, events, active), which helps an agent know what it will get back, but it says nothing about error behavior for invalid IDs or permissions.

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 short sentences, front-loaded with the purpose and the returned fields, with the requirement stated last. Minor redundancy in repeating 'Read-only' which annotations already cover, but there is 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?

For a single-parameter read tool with full schema coverage and annotations covering safety traits, this is close to sufficient; the description even compensates for the lack of an output schema by listing returned fields. Missing only guidance on invalid/missing webhook_id handling.

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% for the single webhook_id parameter, so the schema already carries the semantics. The description only states that webhook_id is required, adding no format, source, or lookup guidance beyond the structured field, making the baseline 3 appropriate.

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 uses a specific verb and resource ('Get details of a specific webhook') and previews the returned fields (URL, events, active status), which distinguishes it from list_webhooks in the sibling set. It does not explicitly name get_transactional_webhook or list_webhooks as alternatives, so it falls short of a 5.

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?

'needs webhook_id' signals the prerequisite, and 'specific webhook' implies the tool is for single-record lookups rather than enumeration. There is no explicit when-to-use/when-not guidance or mention of the sibling list/get alternatives that would disambiguate this from list_webhooks or get_transactional_webhook.

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