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 disclosing side effects and return behavior. It only says that the expression is discarded, which is a useful statelessness hint, but it omits output format, errors, permissions, or any other operational behavior.

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 appropriately short, front-loaded with the verb and object, and contains no filler. The second sentence about discarding the expression is cryptic given the schema mismatch, but the structure itself is efficient.

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?

The definition is critically incomplete: it never identifies which parameter contains the expression, provides no output schema, and offers no usage context. Given seven unrelated schema fields and no annotations, an agent cannot reliably select or invoke this tool based on the description alone.

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?

All seven schema parameters have descriptions, which is a strong baseline, but none of them is an arithmetic expression matching 'a+b.' The description therefore adds no practical mapping between its stated purpose and the actual parameters an agent must supply.

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 names a specific operation, evaluating a+b-style arithmetic, and adds a notable behavior with 'Expression discarded.' However, it is vague about how the expression is supplied and does not map cleanly to any schema parameter, so the stated purpose is only partially actionable.

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 to use this tool versus alternatives, no prerequisites, and no mention of what input actually carries the expression. The sibling list suggests many related shape/check tools, but the description does not exclude or differentiate them.

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