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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds the returned field set, which is genuine value given there is no output schema, but it says nothing about behavior for unknown IDs, partial matches, or result ordering.

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?

A single front-loaded sentence with no filler. The verb, the input format, and the returned fields all appear in one pass with nothing extraneous.

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, two-parameter lookup with no output schema, the description covers input shape and concrete return fields, which is the main thing an agent needs. It falls short only on edge-case behavior (invalid IDs, batch limits), which is a minor gap for a resolver tool.

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%, so both parameters are already documented, including the comma-separated example for carrierRouteIds and the optional correlation role of intentId. The description merely restates the comma-separated ID format, adding no syntax or constraint beyond the schema; baseline 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?

States a specific verb ('Resolve') and resource ('carrier route IDs') and enumerates exactly what the caller gets back: carrier, product code, origin/destination countries, weight band. No sibling tool deals with carrier routes, so the agent can tell it apart from the label/order/surcharge tools without opening the schema.

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 phrase 'Resolve ... to lane details' implies the lookup use case, but there is no explicit statement of when to reach for this tool versus the surcharge or rate tools, nor any prerequisite or exclusion. Usage is inferable rather than stated.

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