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

The annotations already convey read-only, idempotent, and non-destructive behavior, so the description does not need to restate those. It adds minimal behavioral context by mentioning 'performance metrics' as part of the result, but it does not disclose pagination, cursor handling, or output format beyond that.

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 concise sentences with the main action and scope front-loaded. The second sentence adds valuable use-case context without redundancy or unnecessary detail.

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?

Given 10 parameters, no output schema, and no parameter descriptions, the description is not fully complete. It establishes purpose and some use cases, but an agent would still need to infer how cursors, date ranges, search, and volume filters interact, as well as what response shape to expect.

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 0% and the tool has 10 parameters, so the description must compensate by explaining parameters. It does not mention date filters, cursor semantics, search, sorting directions, or send-volume thresholds; it only implies projectId by saying 'a project's'. This leaves the agent to guess from parameter names alone.

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 action and resource: 'List a project's campaigns with performance metrics.' This clearly communicates plural listing versus sibling getters like sm_get_campaign, and the performance-metric detail narrows the output intent. The added use-case sentence reinforces why the tool is useful without obscuring its core 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 gives two explicit use contexts: mapping a member's lastActivityAt onto a real send and locating the latest house send by send_time. This is practical guidance, though it does not explicitly name alternatives or say when not to use this tool rather than a sibling list tool like sm_get_member_campaigns.

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