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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds useful behavioral context by noting the subscriptions are 'resource-scoped' and by instructing the agent to 'Follow any llmContext guidance included in results.' This goes beyond the structured annotations.

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?

The description is concise and front-loaded with the core purpose and filters. The second sentence about llmContext guidance earns its place as an operational instruction. Minor jargon such as 'webhooks group' keeps it from being perfectly crisp.

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 list operation with strong annotations, 100% schema coverage, and an output schema, the description covers the essential selection filters and adds a key follow-up instruction. Pagination and default behavior are already documented in the schema, so no critical context is missing.

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 description coverage is 100%, so the schema fully documents all seven parameters including defaults, enum meanings, and required workspace/environment constraints. The description adds only a high-level mapping of filtering by endpoint or watched resource, which is helpful but not necessary given the exhaustive schema.

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 states a specific action ('List') and a specific resource ('resource-scoped webhook subscriptions'), and it clarifies the two key filtering dimensions: endpoint and watched resource. This clearly distinguishes the tool from siblings like list_webhook_endpoints, create_webhook_subscription, and update_webhook_subscription.

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 its use case by naming the resource and filters, but it does not explicitly say when to prefer this tool over alternatives or when not to use it. There is no exclusions or alternative routing, though the verb and resource make the intended purpose reasonably inferable.

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