add

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

The behavior is transparent for a pure arithmetic operation: it takes two numbers and returns their sum. It does not describe edge cases or return details, but the operation is simple and output schema is available.

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 sentence with no unnecessary words. It is well-structured and immediately understandable.

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?

For a simple arithmetic tool, the description is complete enough for correct use. It lacks explicit edge-case or return-type details, but the operation's simplicity and available output schema reduce the need for further explanation.

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 description says 'two numbers,' which collectively defines both parameters as addends. It does not individually describe a or b, but for addition the individual roles are clear and order is irrelevant.

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 exact purpose: adding two numbers together. It is a specific verb and resource, and it naturally distinguishes from sibling tools like subtract 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?

The description makes it clear that this tool is for addition, and sibling names imply when to use other operations. However, it does not explicitly state when not to use this tool or provide alternative selection guidance.

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