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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description still adds real behavioral context: a hard cap of the latest 100 records, exclusion of event payloads and secrets from the response, and the required webhooks:read OAuth scope.

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 compact sentences, front-loaded with the core action and scope, then auth and safety qualifiers. 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?

With an output schema present, return-value shape needn't be explained, and the description still flags the 100-record cap and payload/secret omission. Only a note on pagination/ordering beyond 'latest' would make it fully complete.

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 coverage is 100% and the schema description already explains the subscription_id (returned by create_webhook/list_webhooks, not a delivery ID or signing secret). The description adds no parameter-level detail beyond the schema, 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?

Specific verb ('Read') plus precise resource ('latest 100 delivery attempts for an owned subscription'), with scope bounded to 100 records. It is clearly distinguishable from the sibling list_webhooks, which enumerates subscriptions rather than delivery attempts.

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 description implies usage by requiring 'an owned subscription', but never states when to reach for this tool versus list_webhooks or create_webhook, and offers no exclusions or alternatives. Usage is inferable but not explicit.

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