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

It discloses critical behavioral traits such as performance limitations ('SLOW,' 'may not complete at all') and the aggregation scope, which are essential operational details not found in standard metadata.

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 highly dense and perfectly structured to front-load critical constraints and guidance before detailing the specific functionality and scope.

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 high-risk/performance nature of this tool, the description is exceptionally complete by providing warnings about failure likelihood and guiding the agent towards more suitable alternatives.

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?

While the schema is 100% covered, the description adds semantic guidance by stating the need to 'narrow' the scope using the `range` parameter, linking the tool's performance directly to parameter usage.

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 defines the resource (account campaigns) and the specific aggregated metrics it returns, distinguishing its role as a full account roll-up.

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 comparative usage guidelines: warns that it is SLOW, suggests alternatives for specific use cases (`analytics_reporting`, `analytics_campaign`), and states the precise condition for its use ('true account-wide roll-up is needed').

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