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

The annotations already establish that this is a read-only, idempotent, non-destructive calculation. Beyond that, the description adds useful model details: Bethe range, Bortfeld (1997), Gaussian straggling, initial energy spread, water-equivalent tissue, and above-200-MeV extrapolation. It does not specify output units or numerical precision, but the behavioral assumptions are unusually well disclosed.

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 two dense sentences with no wasted wording. The purpose and outputs are front-loaded, followed by the computational method and key limitation, which is appropriate for a scientific calculation tool.

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 no-output-schema calculation tool, the description lists the returned quantities and explains the underlying model assumptions and extrapolation limitation. Its main gap is that output units and result structure are not given, so an agent may need external context to interpret the returned values fully.

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 coverage is 67%, so parameter documentation is partly present already. The description adds meaning by mapping 'material' to water or ICRU soft tissue, 'spread_percent' to initial energy spread, and clarifying that high energies are extrapolated beyond the validated range. It does not explain every parameter in depth, but it compensates meaningfully for the partial schema coverage.

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 a specific verb, 'Calculate', and names precise proton-physics quantities: CSDA range, stopping power, Bragg peak, distal R80, and relative dose per fluence. It clearly distinguishes this from siblings such as energy_loss or gamma_dose_rate by focusing on proton Bragg-peak and range calculations.

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 domain and parameter choices imply when this tool is appropriate, namely proton range/dose calculations in water or ICRU soft tissue. However, it does not explicitly compare it with related sibling tools or state when not to use it, apart from noting that energies above 200 MeV are extrapolated.

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