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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Expression discarded', which is irrelevant because no expression parameter exists in the schema. It discloses nothing about side effects, permissions, error behavior, or return format. The description is essentially non-informative and mismatched with the actual tool contract.

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 short sentence, which is concise in length but severely under-specified. It fails to convey any useful information about the tool's operation or parameters, so this is under-specification rather than genuine conciseness.

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?

With 9 parameters, no output schema, and no annotations, the description must explain how the parameters relate to the stated purpose. It does not, making the tool impossible to call correctly. The description is completely inadequate for the tool's complexity.

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%, so the schema already documents all nine parameters with individual descriptions. The tool description adds no additional meaning beyond the schema, so the baseline of 3 applies. No contradictions or extra insight are provided.

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 ('Evaluate a+b style arithmetic') but it does not align with the input schema, which contains no arithmetic expression parameter. This creates confusion about what the tool actually does and how it relates to its parameters. It also fails to distinguish it from any of the 27 sibling tools, many of which could plausibly handle arithmetic.

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 use this tool versus alternatives, nor are there any exclusions, prerequisites, or context hints. The description offers no help in selecting this tool over its many siblings.

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