perform_arithmetic

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, establishing the operation is safe and non-mutating. The description adds that numbers are processed 'in sequence', but it doesn't specify how operations like subtraction or division apply across the sequence (e.g., left-to-right accumulation). The description adds modest behavioral context beyond the annotations but is not exhaustive.

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 concise, with the core action in the first sentence. The Args block repeats some information from the schema but is compact and does not add unnecessary clutter. It is well-structured and efficient.

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?

An output schema is present, so return format is likely covered. However, the description is incomplete regarding the semantics of sequence-dependent operations (subtraction, division). It doesn't clarify the order of operations or whether the first number serves as the initial value, which is critical for correct usage. This ambiguity reduces completeness.

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?

The schema has zero description coverage, so the description must carry parameter meaning. It lists the four operation values and states numbers is a list, but it doesn't define how operations are applied (e.g., whether the first number is the base for subtract/divide). The phrase 'in sequence' gives a hint but remains vague, leaving room for misinterpretation.

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 performs basic arithmetic operations (add, subtract, multiply, divide) on a list of numbers. The name and description align, and the phrase 'basic arithmetic' differentiates it from scientific or statistical siblings. However, it doesn't explicitly contrast with evaluate_math_expression, which may also handle basic operations, so it's not fully distinguishing.

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 provides no guidance on when to use this tool versus siblings like evaluate_math_expression or scientific_calculation. It only describes what it does, without any exclusions or alternative suggestions, leaving the agent to infer suitability.

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