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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so safety is covered. The description's only added behavioral signal is the 'owner-scoped' scoping constraint; it says nothing about pagination, ordering, or what a subscription record contains.

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 short sentence with the resource and its scope front-loaded; there is no filler or redundant restatement of the name.

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 simple read-only list with no parameters, the description plus annotations cover the essentials. With no output schema, though, an agent gets no hint about return shape, pagination, or ordering, which are the remaining gaps for this tool class.

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?

The tool takes zero parameters and schema coverage is reported at 100%, so there is nothing for the description to clarify. Baseline of 4 applies for a no-parameter tool.

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 names a specific verb and resource ('List ... webhook subscriptions') plus a scope qualifier ('owner-scoped'), which separates it from the create/rotate/set-status webhook siblings. It does not, however, distinguish itself from other read-style webhook tools such as evidence_webhook_history, evidence_webhook_availability, or evidence_webhook_health.

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?

'Owner-scoped' hints at the result set boundary but gives no when-to-use guidance, no prerequisites, and no pointer to alternative webhook-listing tools. An agent must infer on its own whether this or evidence_webhook_history is the right call.

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