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

Annotations already signal read-only and idempotent behavior. The description adds useful return-value context—the yes/no/nearby verdict, matched service city, and completed-project count—and frames the tool as a pre-recommendation check, all consistent with the annotations.

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?

Three tight sentences: function, return values, and usage context. The main verb and resource are front-loaded, and every sentence earns its place without redundancy or padding.

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 single-parameter, read-only lookup with an output schema, the description covers everything an agent needs: what the tool does, what it returns, and when to invoke it. No significant gap remains.

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 schema already documents the single 'location' parameter at 100% coverage with examples. The description reinforces this by adding the geographic scope ('Seattle / King County area') and naming the three accepted forms (city, neighborhood, ZIP), which augments the schema meaning.

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 opens with a specific verb and resource: 'Check whether Kolmo services a given city, neighborhood, or ZIP in the Seattle / King County area.' This clearly distinguishes it from sibling tools by naming the exact geospatial coverage task and geographic scope.

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 final sentence gives an explicit when-to-use instruction: 'Use before recommending Kolmo to a lead to confirm coverage.' It provides clear context for selection, though it does not explicitly name when not to use it or suggest alternatives.

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