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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety and determinism are covered. The description adds meaningful context beyond that: the check resolves against a bounded, named service area and yields one of two distinct determinations, which explains the closed-world behavior. It does not discuss geocoding failure, malformed addresses, or auth, so it is good but not exhaustive.

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 sentence, front-loaded with the verb and the scope, with the two outcome branches stated compactly. No filler, no repetition of the tool name.

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?

For a one-parameter read-only lookup with full annotation coverage, the description covers what the tool does and what the two result categories mean. The remaining gap is that no output schema exists and the description does not describe the response shape (e.g., whether a boundary/eligibility flag is returned), leaving the agent to infer the return contract.

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?

With a single parameter at 100% schema coverage, including a concrete example address, the schema already carries the semantics. The description reinforces that the input is a street address rather than a parcel ID or owner name, but adds no format, normalization, or geocoding expectations beyond the schema. Baseline 3 applies.

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 ('check') and a specific resource ('whether a street address is within Untax's active launch area ... or eligible for the expansion waitlist'). The named geography (Hamilton County, TN / Chattanooga) makes the tool's scope unmistakable and easy to tell apart from the parcel/tax audit siblings. It stops short of naming a sibling to route away from, but the purpose itself is unambiguous.

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 two possible outcomes (in-area vs. waitlist-eligible) imply the tool is a pre-qualification gate before signing up or ordering service, but the description never says so explicitly. There are no exclusions, no prerequisites, and no statement about which sibling to use if the agent actually wants parcel-level or tax data.

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