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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so the closing 'Read-only' is redundant. The description nonetheless adds real value beyond them: the required OAuth scope (webhooks:read) and the guarantee that signing secrets are never returned again, which is a non-obvious security behavior for a listing endpoint.

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?

Front-loaded with the resource and scope, and every sentence carries distinct information (alternatives, downstream use, auth, secret handling). It is somewhat telegraphic and the 'never returned again' phrasing is slightly awkward, but nothing is wasted.

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?

An output schema exists, so return values need no explanation, and the description covers scope, auth, alternatives and secret behavior. The remaining gap is how large result sets are handled (pagination or ordering) for a no-parameter listing tool.

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?

Zero parameters, so per the rubric the baseline is 4. The description adds no parameter detail, and notably no pagination/filtering control is mentioned anywhere, though the schema is empty.

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 (order event subscriptions) plus the ownership scope ('owned by this application and buyer session'). It explicitly distinguishes itself from the sibling list_webhook_deliveries, so an agent can route correctly 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?

Gives an explicit when-not: 'Use list_webhook_deliveries for delivery attempts, not this listing.' It also names delete_webhook as a downstream consumer of the returned IDs, which tells the agent why to call this first.

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