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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is covered. The description adds that results are 'bounded' and 'recent', signaling truncated, recency-limited output rather than full history – useful context, but it stops short of stating ordering, pagination, or a window definition.

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?

A single, front-loaded sentence with zero filler; every word ('bounded', 'recent', 'one', 'deliveries') carries meaning. No restructuring would improve it.

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 read-only bounded-list tool whose annotations cover safety and which has no output schema, the description covers the core. But an agent still lacks ordering (newest-first?), what a 'delivery' record contains, and how 'bounded' relates to the limit parameter, leaving the definition adequate rather than 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 0%, so the description must carry parameter meaning. 'one webhook subscription' implies the required subscriptionKey, and 'bounded recent' gestures at the limit parameter, but neither default (20), maximum (50), nor the key's format/length constraints are explained. It partially compensates but leaves real gaps.

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 'List' and resource 'deliveries' scoped to 'one webhook subscription', which distinguishes it from sibling list_webhooks (webhooks, not deliveries) and from webhook_health/availability. It does not explicitly name a sibling, but the verb+resource pairing is precise enough that an agent can differentiate.

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?

Usage is implied by 'recent deliveries for one webhook subscription' – an agent infers this is for inspecting delivery history. However there is no explicit when-to-use, no contrast with webhook_health or webhook_availability, and no stated prerequisites (e.g., that a valid subscription key is required).

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