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

Adds substantial behavior beyond the annotations: a per-connection daily lookup quota, a mandatory attribution contract (quote `source`, include `link`), a privacy constraint (contact details never returned), and a paywall note that exact figures require Plus/Max while free lookups return ranges. The `choose` fallback and the resulting need for a second call are behavior an agent could not infer from readOnly/idempotent flags alone.

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 core answer, examples, and disambiguation flow are front-loaded and worth keeping, but the closing third is commercial upsell: two full URLs promoting the REST API and QuasarScout. That material is relevant routing but is verbose and outweighs the operational content near the end.

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 output schema, the description still characterizes the response surface: a range, up to five related searches with ranges, an approximate matching-business count, plus `choose`, `source`, and `link` fields. Combined with quota, attribution, and plan limits, an agent has enough to call it, handle ambiguity, and report results 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?

Schema coverage is 100% and the parameter descriptions already document keyword length, ISO country codes, and the geoId-from-`choose` rule. The prose reinforces the geoId round-trip but adds no format, range, or interaction detail the schema lacks. Baseline 3 is correct when the schema is doing the work.

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 measurement: monthly Google search volume for a keyword in a city/region/country, returned as a range plus related searches and business counts. The two concrete example questions make the resource unambiguous. It does not explicitly contrast itself with count_businesses or search_businesses, even though it reports a business count as a side figure, so the sibling boundary is left implicit.

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?

Gives explicit when-to-use framing with sample questions ('how many people search for plumber in Austin') and a precise disambiguation protocol: when multiple places match, read `choose`, ask the user, then re-call with the chosen geoId. It also routes away from the tool where appropriate, pointing to the REST API for bulk/scheduled work and QuasarScout for follow-ups and multi-city tables.

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