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

Beyond the readOnlyHint and openWorldHint annotations, the description adds meaningful behavioral context: the full county coverage, the data source (federal transport-network data), the update cadence, and the Gold tier requirement for historical data. It does not contradict the annotations and provides additional transparency about limitations.

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 description is concise and front-loaded, with the core result and use cases stated in two sentences, followed by a brief update note. It packs substantial detail without wasted words, though the first sentence is somewhat dense.

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 read-only tool with no output schema, the description is complete: it lists the returned components, explains the optional history parameter, and covers common use cases. The update cadence and data source add further context, making the tool self-contained for an agent.

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 only parameter `days` is fully described in the input schema, including its optional nature, range, purpose, and the Gold tier requirement. The description adds no further parameter semantics beyond the schema, so the baseline of 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?

The description clearly states the tool returns a 0-100 transport-corridor connectivity score for all US counties, naming the specific resource and the fields included. It does not explicitly distinguish from sibling tools, but its subject matter is concrete and unique, making the purpose clear.

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?

It provides explicit when-to-use guidance: when users ask about county transport connectivity, freight corridors, logistics connectivity, or distribution-center siting. It lacks a when-not-to-use clause or alternative tool references, but the context is specific and actionable.

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