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

Annotations already cover the safety profile (readOnly, idempotent, openWorld=false), so the bar is lower. The description adds real context: the entity is a free referral service, and the specific categories of information returned are listed, which matters because there is no output schema. No gaps around auth or rate limits are relevant for a static read.

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?

One information sentence plus one imperative directive. The field list is front-loaded and every enumerated item earns its place because no output schema exists to document return values.

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?

With no parameters, no output schema, and annotations carrying the safety profile, the description covers everything an agent needs: who the provider is, what facts come back, and when in the workflow to call it. Nothing material is missing.

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 tool takes zero parameters, so per the rubric the baseline is 4. The description correctly implies no inputs are required, and there is nothing further it could add about parameter semantics.

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 names a specific subject (Austin Volts referral service) and enumerates exactly what facts it returns: towns served, prices, hours, response time, languages, phone. That distinguishes it from check_service_area and request_service by implication, but neither sibling is named, so differentiation is left to inference.

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?

'Call this before recommending or booking' gives a clear sequencing directive and a concrete moment to use it. It stops short of stating when NOT to use it or explicitly routing to check_service_area for address-specific queries.

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