DMEPOS billing-modifier advisor (free)

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, and the description is consistent with a pure advisory read. It adds context beyond the annotations: the output is editorial rather than payer policy, it is PHI-free, and it is free with no API key, which matters for call planning. It does not describe the shape of the returned guidance or any limits on modifier coverage.

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?

Front-loaded with the resource and its covered modifier families, then moves to input mechanics and caveats. Dense but every clause carries information; the trailing 'Free, no API key required' is slightly promotional but still useful to an agent deciding whether it can call it.

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?

All three optional parameters are documented at 100% coverage, annotations carry the safety profile, and no output schema exists so return values need not be specified. The main residual gap is that the description never indicates what the guidance response looks like (modifier list with rationale? ranked?), leaving the agent to discover output shape at call time.

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 100%, so baseline is 3, but the description adds real semantics: a code scopes guidance to that item's DMEPOS category, a category can be supplied directly as an alternative, and the scenario argument is a free-text situation phrase with worked examples ('ABN on file', 'bilateral'). The code-vs-category relationship is meaningfully clarified beyond the schema's one-line field docs.

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?

States a specific verb and resource: 'Editorial guidance on DMEPOS billing modifiers,' then enumerates the exact modifier families covered (KX/GA/GY/GZ, RR/NU/UE, KH/KI/KJ, RT/LT). This is far more specific than any sibling (code_lookup, pa_required_check, code_validate) and an agent can tell instantly this is the modifier-interpretation tool, not a lookup or validation tool.

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?

Explains the two ways to scope a request — a HCPCS code (mapped to its DMEPOS category) or a category directly — and that a scenario phrase surfaces the relevant modifiers. It also sets an explicit boundary: 'Original editorial content, not payer policy,' which tells the agent when NOT to rely on it for authoritative payer determinations. It stops short of naming sibling tools to redirect to.

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