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

Annotations already declare readOnlyHint=true, so the tool is known to be non-destructive. The description adds context on the specific analyses performed (contribution margin, break-even, margin of safety, price leverage) and the optional nature of current volume, which enhances understanding of the tool's behavior beyond the 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 two sentences, front-loaded with the core purpose, and contains no unnecessary words. Every sentence adds meaningful information, achieving maximum conciseness.

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?

Despite no output schema, the description enumerates all key outputs (contribution margin, break-even units and revenue, margin of safety, price leverage). Combined with detailed parameter descriptions, the tool's functionality is fully conveyed for a data analysis tool of moderate complexity.

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%, so parameters are well-documented. The description adds value by explaining how parameters relate to outputs (e.g., 'current volume' enables margin-of-safety analysis) and summarizing the overall analysis, which goes beyond the schema descriptions.

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 computes break-even units and revenue, contribution margin, margin of safety, and price change leverage. It uses specific verbs like 'needed to cover costs' and 'how much pricing moves it', making the purpose unmistakable and distinct from siblings such as 'unit_economics'.

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 cost-volume-profit analysis but does not explicitly state when to use this tool versus alternatives like 'unit_economics' or 'pricing_margin'. No when-not-to-use or alternative tools are mentioned, providing only implicit guidance.

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