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

Since no annotations are provided, the description carries the full burden. It discloses that the tool is 'Free' and lists the exact fields returned, including status enums and event types. It implies a read-only operation by saying 'Lists,' but it does not explicitly state that it has no side effects or describe error conditions. Overall, it provides substantial behavioral context beyond the schema.

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 well-structured. It opens with the main action, then lists return fields in a dense but organized manner. The second sentence adds important context (free, use case) without unnecessary fluff. Every sentence contributes value, and the length is appropriate given the absence of an output schema.

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 no output schema, the description comprehensively covers the return values by enumerating all fields and their possible statuses/events. It also explains the tool's purpose and cost. For a two-parameter list operation, this provides sufficient context for an agent to invoke it correctly and interpret results.

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 input schema already provides 100% coverage for both parameters (wallet and only_active) with clear descriptions. The tool description adds minimal parameter-specific detail, only mentioning 'for a wallet' implicitly. Since the schema handles parameter semantics well, the description adds little extra value, warranting the baseline score.

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 clearly states the tool's function: 'Lists all reputation-drift / attestation-freshness webhook subscriptions for a wallet.' It uses a specific verb ('Lists') and resource, and distinguishes itself from sibling tools like subscribe/unsubscribe by focusing on listing existing subscriptions. The additional mention of what it returns further clarifies its purpose.

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 provides a clear use case: 'Use to audit what's being monitored and how many alerts have already fired before paying for another subscription.' This tells the agent when to use the tool. However, it does not explicitly mention when not to use it or name alternative tools, so it lacks explicit exclusions.

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