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

No annotations are present, so the description carries the full burden of behavioral disclosure. It only says 'Expression discarded,' which is a useful data-retention hint, but it does not describe return values, side effects, permissions, or error behavior; the discard claim is also unmoored because no expression parameter exists in the schema.

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 text is short and front-loaded, but the brevity reflects under-specification rather than useful conciseness. The second sentence, 'Expression discarded,' adds confusion because no expression parameter is defined anywhere.

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 nine-parameter tool with no annotations and no output schema, this description is not remotely complete. An agent cannot determine which parameter to populate, what the tool returns, or what conditions warrant calling it.

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 coverage is 100%, so the schema individually documents all nine parameters, but the description adds no mapping from those parameters to the advertised arithmetic evaluation. It introduces an 'expression' concept absent from the schema and fails to indicate which parameter, if any, should carry the expression.

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 says 'Evaluate a+b style arithmetic,' which is close to a restatement of the tool name calc-eval and adds little specificity. It names no input parameter or output, and the schema exposes nine unrelated parameters with no arithmetic expression field, so the stated purpose does not map onto any actual argument.

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 on when calc-eval should be used instead of sibling tools such as validate-json or search-query-len, and no exclusions or context are provided. An agent gets no help deciding whether this tool is the right choice for a given task.

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