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

With no annotations, the description carries the transparency burden. It discloses key financial assumptions such as the £25/week umbrella margin, 15% employer NI funded from the rate, and gross pay after employer costs. However, it never explicitly states that this is a pure calculation with no persistent side effects or what the response contains.

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 compact and front-loaded with the action, and its list format keeps related information together. The redundant 'calculator calculator' phrase is a minor flaw, but it does not materially hurt comprehension.

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 input schema fully documents all parameters, but there is no output schema. The description lists computed components but does not clearly state the return format or confirm that the tool returns a final take-home figure, so an agent must infer some output behavior.

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 parameters have full descriptions in the schema, so the baseline is 3. The description adds contextual framing by indicating which assumptions feed the calculation, but it does not add meaningful per-field semantics beyond what the schema already documents.

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 uses the imperative 'Run' with a named resource, the Locum take-home calculator, making the action and subject clear. It lists the calculator's major outputs and assumptions, but it does not explicitly distinguish this tool from the sibling calculator_describe beyond the verb and name.

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 explicit guidance about when to use calculate versus calculator_describe or any other sibling tool. The only usage hint is the fallback-to-defaults behavior, which addresses invocation robustness rather than tool selection.

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