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

Beyond the readOnlyHint and destructiveHint annotations, the description discloses meaningful behavioral constraints: maximum row counts, the fact that counts reflect scanner bias rather than unique players/trips, and that the End has no released data. These directly affect result interpretation and are not available from 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 compact sentences, each carrying distinct useful information: purpose, row limits, bias caveat, and coverage caveat. No filler or redundant restatement of the schema.

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 an output schema present and annotations covering safety, the description still adds essential caveats about row limits, scanner bias, and missing End data. An agent has enough to invoke the tool correctly and interpret results responsibly.

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 description coverage is 100% for both parameters, so the baseline applies; the schema already documents dimension and direction values. The description adds context about bucketization and the End exclusion but does not need to repeat parameter syntax.

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 states a specific verb ('Get') and resource ('released historical Nocom highway observation counts') and clarifies the aggregation axes: compass direction and fixed 30-day buckets. This is distinctive enough to separate it from siblings like get_nocom_dataset, get_nocom_periods, or get_highway without inspecting schemas.

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 description implies a narrow read-only lookup role but does not explicitly name alternatives or state when to prefer this tool over closely related siblings. The 'End has no released highway series' note gives one exclusion, but general selection guidance is left to inference.

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