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

With no annotations, the description carries the full burden of behavioral disclosure. It transparently explains the free preview (severity, totals, issue count), the paid full report (line-by-line breakdown and up to 5 dispute letters), and the unique unlock URL for payment. This gives the agent critical behavioral context that payment is required.

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 well-structured paragraph with no redundant sentences. It front-loads the core function, then explains the preview, payment requirement, and unlock URL. Every sentence earns its place, providing necessary information for an agent deciding whether and how to invoke the 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?

Despite lacking an output schema, the description adequately characterizes return values: the free preview contents, the full report breakdown, and the unlock URL. It also indirectly conveys the tool's moderate complexity. It does not go into failure modes or detailed data source nuances, but it is sufficient for the agent to set user expectations.

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 single parameter billText is fully described in the input schema (100% coverage), including its content and the unsupported image/PDF types. The tool description itself does not add parameter-specific details, but the schema already does the heavy lifting, so a baseline 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 opens with 'Runs a full audit on a medical bill' — a specific verb and resource — and enumerates the six federal data sources cross-referenced. This clearly differentiates it from the sibling lookup tools (get_dispute_scenario, lookup_cpt_rate, lookup_hospital), which handle narrower lookups.

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 clearly implies its use case: comprehensive bill auditing via phrases like 'full audit' and 'cross-references every charge against six federal data sources.' However, it does not explicitly name alternatives or state when not to use it, so it lacks the explicit when/when-not guidance of a 5.

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