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

With no annotations provided, the description carries the full burden, but it only mentions that the expression is discarded. It does not disclose side effects, permissions, output behavior, or error conditions.

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 very short and front-loaded with the main action. The second sentence is ambiguous but does not add unnecessary length or clutter.

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 nine parameters and no output schema, the description is far too sparse. It omits the return format, which parameter to supply, example usage, and any edge-case behavior, so an agent cannot reliably call the tool.

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 lists nine unrelated string parameters, none of which is an arithmetic expression or operand. The description does not explain how any parameter maps to 'a+b', making parameter usage effectively impossible to infer.

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 action ('Evaluate a+b style arithmetic') and the tool name reinforces it, but 'Expression discarded' is ambiguous and no expression parameter appears in the schema, leaving the intended operation partially unclear.

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?

No guidance is given on when to prefer this tool over siblings or when not to use it. The arithmetic phrasing implies a use case, but there is no concrete context or alternative comparison.

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