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

With no annotations, the description must carry the transparency burden. It discloses that the tool is 'Free, no authentication required' and lists the data source (CMS) and returned fields. However, it does not disclose whether multiple matches are returned (given 'partial match supported' on name) or any limitations like pagination or error behavior. This is a notable gap for a lookup tool with optional parameters.

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 sentences, front-loaded with the core purpose and output fields. The second sentence adds use-case context and access details. Every sentence contributes value with no fluff or redundancy.

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?

There is no output schema, so the description should clarify the return shape (single hospital vs. list). It lists fields but doesn't state whether the result is a single object or an array, nor what happens on no match. The tool's complexity is low, but these missing details leave some ambiguity for agents.

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 input schema provides 100% coverage with descriptions for all three parameters (ccn, name, state). The description adds minimal param-specific context beyond what the schema already says. It does not expand on parameter usage or relationships, so the schema carries the weight, making a baseline score of 3 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 function: 'Returns hospital metadata from CMS data' with a specific list of fields. It distinguishes the tool from siblings (which deal with billing, disputes, CPT rates) by focusing solely on hospital information.

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 provides a clear use case: 'Useful when a patient mentions a specific hospital and wants to know the facility's federally-published quality profile and whether charity care is available.' It implies the tool is for patient-provided hospital names/CCNs, though it doesn't explicitly mention when not to use it or alternative tools. The siblings are sufficiently distinct in domain, so the guidance is adequate.

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