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

Annotations include readOnlyHint=true, so the description doesn't need to repeat safety information. It adds value by detailing the informational content (what each level is, who it suits, facility counts, directory URLs) and its role in the workflow. While it doesn't discuss edge cases or limitations, the tool is a simple read-only lookup, so this is sufficient.

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?

Two sentences: the first packs the continuum and the types of information provided; the second gives clear usage guidance. No wasted words, no repetition of schema or annotations, and the information is front-loaded.

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?

Given that there are no parameters and an output schema exists, the description fully covers the tool's purpose, scope, and usage context. It tells the agent exactly what to expect (explanations, suitability, counts, URLs) and when to use it, making it complete for an AI agent to invoke correctly.

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 has zero parameters, so the baseline is 4. The description appropriately says nothing about parameters, as there are none to explain. Adding parameter-specific details would be redundant.

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 explains the substance-use-disorder intensity-of-care continuum, enumerating specific levels (detox, residential, IOP/PHP, outpatient, MAT, sober living). It distinguishes from sibling search/list tools by framing this as an educational resource for understanding treatment options before searching.

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 explicitly says 'Use this to help someone understand which kind of treatment fits before searching,' providing a clear when-to-use directive and implying that search tools are the subsequent step. This effectively differentiates it from the sibling search/list tools.

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