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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states what the tool returns (units, revenue, contribution margin) and explains the concept of contribution margin. It does not mention side effects (likely none for a pure calculation) or edge cases, but it adequately covers the behavioral expectation that this is a read-only computation that produces specific numeric outputs.

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 compact, with the purpose front-loaded, followed by output details and parameter list. Every sentence earns its place, and there is no redundant filler. It is well-structured for quick parsing by an agent.

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 there is no output schema, the description adequately explains what the tool returns and what the output means. It defines the contribution margin and mentions both required and optional inputs. It does not detail edge cases or formula assumptions, but for a straightforward calculator with well-documented schema parameters, the description is sufficiently complete for correct invocation.

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 each parameter already has a semantic description. The tool description merely restates which parameters are required/optional and stresses using exact English names, which adds no new meaning beyond the schema. It does not deepen understanding of parameter relationships or constraints, so a baseline of 3 is appropriate.

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 specific purpose: calculating the break-even point in terms of units and monthly revenue, plus the contribution margin. It names the exact output metrics and distinguishes itself from the many sibling financial calculators by focusing on break-even analysis. The verb 'Calcula' plus the resource 'ponto de equilíbrio de um negócio' makes it unambiguous.

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 implicitly indicates when to use this tool (when break-even analysis is needed) and explains what it computes. It does not explicitly name alternatives or state when not to use it, but the niche purpose is clear enough for an agent to select it appropriately among the many calculate_* tools. This meets the 'clear context, no exclusions' bar.

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