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

The description discloses return values (simplified numerator/denominator, decimal value, gcd, percentage), going beyond the annotations which already indicate read-only and idempotent behavior. It does not mention edge cases, but the schema handles the denominator non-zero constraint.

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 a single, front-loaded sentence that efficiently conveys the tool's purpose and return values with no redundant information.

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 simplicity of the tool, the rich annotations, and the presence of an output schema, the description is complete. It clearly states what the tool does and what it returns, with no critical gaps.

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 coverage is 100% with descriptions for both parameters. The description adds some context by restating that numerator and denominator are the fraction parts, but does not provide additional syntax or format details beyond the schema.

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's function with a specific verb ('Simplify') and resource ('a fraction'), and specifies the outputs. It distinguishes itself from sibling calculators by focusing specifically on fraction simplification.

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 (when you need to simplify a fraction) but provides no explicit exclusions or alternatives. No guidance is given for when not to use this tool or how it compares to related calculators like percentage-calculator.

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