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

With no annotations provided, the description carries the full burden. It discloses the update frequency ('Updated every 30 minutes from US Customs and Border Protection'), the data returned (delay in minutes, lanes open, port status), and coverage scope. This provides useful behavioral context beyond mere 'get data' and helps set expectations, though it omits any error/availability details.

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 a compact three-sentence paragraph that front-loads the primary purpose, then adds data details and use cases. It is efficient, but includes a long list of port examples that, while useful, could be trimmed for strict minimalism.

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 simple no-parameter tool with no output schema, the description fully covers what it does, what data it returns, how fresh the data is, geographic scope, and typical use cases. It is complete and self-contained.

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 tool has zero parameters, and the baseline for 0 parameters is 4. Since there is no input schema to clarify, the description doesn't need to explain parameters, but it does adequate context for how the tool is invoked (no arguments needed).

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's function with a specific verb and resource: 'Get real-time commercial border crossing wait times at US-Mexico and US-Canada ports of entry.' It distinguishes this from siblings like port congestion monitors by focusing specifically on border crossing delays and commercial vehicles. This is a precise, distinctive purpose.

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 provides clear context for when to use the tool, noting it is 'Used by logistics companies, freight brokers, and trucking operations to route cross-border shipments through the fastest crossing points.' However, it does not explicitly mention when not to use it or compare with alternative sibling tools, so it falls slightly short of a perfect score.

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