List Audiences

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is clear. The description adds that the tool returns member and subscribed counts, which is useful but does not disclose any other behavioral traits (e.g., pagination behavior, rate limits). The description does not contradict 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 a single sentence that efficiently conveys the tool's purpose and key output. It is front-loaded with the action and resource, with no unnecessary words or redundancy.

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 list tool with pagination and an existing output schema, the description is sufficient. It explains what is listed and mentions the counts, while the parameters are fully documented in the schema. No further elaboration is needed.

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% for both parameters (limit and cursor), so the schema already provides adequate documentation. The tool description does not add additional meaning beyond what the schema offers, resulting in a 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 action (list), resource (newsletter audiences), scope (authenticated organization), and additional output (member and subscribed counts). It effectively distinguishes this from sibling tools like shipmail_list_newsletters (which lists newsletters) and shipmail_get_audience (which retrieves a single audience).

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 usage for obtaining a summary list of audiences with counts, but it does not explicitly state when to use this tool versus alternatives (e.g., shipmail_get_audience for a specific audience). No context or exclusion criteria are provided, so guidance is minimal.

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