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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered; the description adds value with the plan/tier gate and the exact field set returned (including lastTriggeredAt and failCount), which hints at delivery-health semantics. It doesn't cover pagination behavior (what happens when more than `limit` webhooks exist), which is the remaining behavioral gap for a list tool.

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?

Three short, front-loaded sentences with zero filler: purpose first, return shape second, routing and gating last. Every clause carries information an agent needs.

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?

There is no output schema, so the description correctly enumerates the returned fields, and the plan gate covers the failure mode an agent would otherwise hit blind. What's missing is pagination guidance for a 2-param list endpoint (cursor semantics), the main thing an agent could still get wrong.

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 50%: `limit` is well documented in the schema (default 50, max 100) but `cursor` has no description anywhere, and the description says nothing about paging or how to use the cursor. It neither compensates for the gap nor adds meaning beyond the schema, so a mid-range score is 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?

States a specific verb and resource with scope ("List webhook subscriptions in this org"), and the return-field enumeration makes clear it is the collection view, not a single-resource read. An agent can distinguish it from get_webhook and from list_webhook_deliveries/list_webhook_events without opening a schema.

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?

Explicitly routes the agent: "PREFER get_webhook for the secret + audit fields," which names the alternative tool and the condition that selects it. It also discloses the entitlement prerequisite ("Plan gate: webhooks (BUSINESS+)"), so an agent knows when the call will be rejected rather than silently failing.

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