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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety and idempotency profile is covered. The description adds the lane-level granularity of the data, but says nothing about freshness, refresh cadence, or how ports are matched — modest added value.

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?

Two sentences, front-loaded with the resource and scope, followed by a compact arg hint. No filler or restated noise.

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 one-parameter read tool with an output schema (so return values need not be explained), the description covers purpose, scope, and argument format. The only gap is the absence of usage context relative to siblings and any note on data freshness.

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 0%, so the description carries the burden and does so: it names the parameter, explains it accepts either a port name or port number, and gives a concrete example ('San Ysidro'). That materially reduces invocation ambiguity for the single required parameter.

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 resource (land border crossing wait times) with explicit scope (US borders with Canada and Mexico) and granularity (by lane). This cleanly distinguishes it from the sibling airport_security_wait, which covers airports rather than land ports of entry.

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 scope phrase 'US borders with Canada and Mexico' implies when the tool applies, but there is no explicit when-to-use statement, no exclusions, and no named alternative (e.g., airport_security_wait for airports). Usage is inferable but not guided.

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