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

With no annotations, the description carries the full behavioral burden, but it only states 'Expression discarded.' This hints at non-persistence but does not clarify whether the tool returns a result, performs a side effect, or requires any specific input. The unrelated schema fields are left entirely unexplained.

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 with no wasted words, but the second sentence is ambiguous and the whole thing lacks connection to the large schema. It is concise in length but not in clarity, earning a middle score.

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?

Despite having 9 schema parameters and no output schema or annotations, the description fails to explain what inputs the tool accepts, what it returns, or why properties like host, json, and query exist. An agent cannot safely infer how to call this tool, making the description drastically incomplete.

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 baseline is 3. The description adds no parameter-level detail and its 'a+b style' reference does not correspond to any property in the schema, so it neither helps nor harms the already self-sufficient parameter descriptions.

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 'Evaluate a+b style arithmetic' essentially restates the calc-eval name without identifying which schema parameter carries the expression. It gives a generic verb and object but fails to map to any of the 9 unrelated properties, making it closer to a tautology than a usable purpose statement.

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 on when to use this tool versus its many siblings, no explicit conditions, exclusions, or alternatives. The only implied context is arithmetic evaluation, which is not enough for an agent to decide between calc-eval and other shape/validation tools.

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