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

There are no annotations and almost no behavioral disclosure. The description states that an expression is discarded, but does not clarify side effects, return values, error behavior, or whether the tool has any persistent effect.

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 extremely short but its second sentence, 'Expression discarded,' actively confuses rather than clarifies. The space is not used to convey necessary information about the evaluation behavior, inputs, or outputs.

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 nine optional parameters, no required parameters, no output schema, and a description that does not tie any parameter to the stated arithmetic purpose, the description is far too incomplete for an agent to call this tool correctly.

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?

Although every parameter has a description, the descriptions are irrelevant to arithmetic evaluation (e.g., 'Git ref name; discarded after the shape check', 'City name for a public weather hint'). No parameter corresponds to the expression that is supposedly evaluated, so the schema adds no meaningful semantic guidance.

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 claims to evaluate a+b style arithmetic, but the input schema contains no expression parameter and instead lists unrelated optional strings like ref, url, city, feed, host, json, path, zone, and query. The phrase 'Expression discarded' contradicts the idea of evaluation, leaving the tool's actual purpose 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 provided about when to use this tool versus any sibling tool. The description does not explain what kind of arithmetic expressions are accepted, what inputs are relevant, or what outputs callers should expect.

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