Calculator

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

With no annotations provided, the description carries the burden of behavioral disclosure. It explains the core operation but does not mention edge cases like division by zero, result format, or error behavior. However, the tool is a simple stateless arithmetic operation and an output schema is present, so the gap is moderate rather than severe.

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 concise, front-loaded sentence that immediately conveys the tool's purpose and supported operations. There is no wasted text or unnecessary detail.

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?

The tool is simple, parameters are fully documented in the schema, and an output schema exists, so the basics are covered. The description is missing guidance on edge cases and how to choose between this and the sibling arithmetic tools, leaving minor but real 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 description coverage is 100%, with all three parameters ('a', 'b', 'operation') already documented, and the operation parameter has an enum. The description adds no additional parameter semantics, so the schema carries the explanatory load.

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 states a clear verb and resource ('Perform arithmetic calculations') and enumerates the supported operations. It is distinct from 'echo' and 'get-time', though it does not explicitly differentiate itself from the overlapping sibling tools 'add' and 'multiply'.

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?

There is no guidance about when to use 'calculate' versus the sibling tools 'add' or 'multiply'. The description only says what the tool does, not when it should be preferred over alternatives, leaving the agent to infer routing.

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