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

With no annotations, the description carries the full burden. It discloses that the tool only reports what is and isn't calculated, and that the agent should not improvise calculations. It does not mention side effects, but the tool is inherently read-only and informational.

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, compact sentence that front-loads the core function (what is calculated) and immediately provides the critical usage instruction. Zero wasted words.

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 simple informational tool with one parameter and an output schema present, the description is complete. It states what the tool does, how to behave with it, and the existence of an output schema covers the return format.

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?

The only parameter is 'lang' with an enum and default in the schema. The description does not mention it, but the schema fully covers its meaning. Since coverage is 0% but the parameter is trivial and self-explanatory, the baseline of 3 is appropriate.

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 clearly states the tool's purpose: it tells the agent what the server calculates and what it does not, serving as a capability reference. It is distinct from all sibling tools, none of which are about server capabilities, and the verb 'calculate' is specific to the domain.

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?

The description gives clear usage context: use it before promising a method to a person, and explicitly tells the agent not to fill in missing calculations itself. It does not name alternatives but implies when to consult this tool (before making promises).

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