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

Annotations already declare readOnlyHint=true, indicating no side effects. The description adds that the tool returns a 'structured, audited deliverable' and mentions server-side validation, which is consistent. However, it does not elaborate on what the deliverable contains, authentication needs, or rate limits. The behavioral insight is adequate but not enriched 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 three sentences, reasonably concise and front-loaded with the tool's identity. The reference case adds some length but is relevant. It could omit the reference case or integrate it more efficiently, but overall it wastes little space.

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 the tool's complexity (nested objects, 5 parameters, no output schema) and the presence of many related sibling tools, the description is insufficient. It does not explain the deliverable's structure, how results are audited, or how to handle errors. The absence of output schema and the high parameter count demand a richer description to guide the agent effectively.

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 description does not explain any parameters beyond the schema; it merely says 'send the documented case fields.' With schema coverage at only 20% (only async described), the description fails to compensate by clarifying the purpose of the many nested fields (e.g., company properties, account signals). A tool with complex inputs requires more parameter guidance.

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 identifies the tool as an anti-churn analysis tool that returns a structured deliverable for C-suite (CRO). The reference case adds specificity. However, it does not explicitly differentiate from sibling tools like renewal_optimizer, save_plays, or upsell_hunter, which operate in adjacent spaces.

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 concrete reference case (Spendesk) indicating a typical use case, but lacks explicit guidance on when to use this tool versus alternatives, or any exclusion criteria. The phrase 'send the documented case fields' implies a specific input format but does not define the context of use relative to other tools.

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