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

The description explicitly states 'Read-only: returns owned webhook subscriptions without changing them,' which aligns perfectly with the readOnlyHint annotation. No contradiction exists, and the 'owned' scope adds clarity beyond the annotation.

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 two sentences, tightly packed with purpose, usage trigger, and read-only nature. No fluff or redundant phrasing.

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?

With an empty parameter schema and no output schema, the description fully covers what the tool does, when to use it, and points to a related tool for event discovery. Nothing essential 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?

The schema has no parameters, so coverage is effectively 100%. Per the baseline rule, a score of 3 is appropriate since the description adds no parameter-specific information (none needed).

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 verb ('list') and resource ('webhook subscriptions'), and clearly defines the trigger ('when the user asks which webhooks... are configured'). It implicitly differentiates from other list tools by focusing on webhook subscriptions, and explicitly references list-webhook-events for event keys.

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?

It provides explicit 'when to use' guidance ('Use this when the user asks...') and names an alternative (list-webhook-events) for discovering valid event keys, giving the agent clear direction on tool selection.

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