Show a route segment

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorld=false, so safety is fully covered. The description adds essentially nothing beyond that: no statement about behavior when routeId does not belong to shipmentId, whether a missing segment errors or returns empty, or whether the segment payload is trimmed. With annotations doing the heavy lifting, this is a pure restatement.

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?

It is short and front-loaded, so nothing is buried. But the entire first line duplicates the title verbatim and the second line only rephrases it, meaning neither sentence earns much space beyond the title already shown to the agent.

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 two-parameter read tool with rich annotations and full schema documentation, very little prose is required, so the definition is close to adequate. The one genuinely useful thing left unsaid is the compound-key semantics: what happens if routeId is valid but not a segment of shipmentId, which an agent calling this tool could easily get wrong.

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% and both parameters are required and documented, including their provenance ('from list_shipment_routes', 'from list_shipments'). The description adds no additional meaning about the shipmentId/routeId pairing constraint, so the baseline of 3 for complete schema coverage 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 states a verb and resource ("Show a route segment ... Returns one route segment of a shipment"), which tells an agent this is a single-segment fetch rather than a list. However, the first line is a verbatim restatement of the title, and it never explicitly distinguishes the tool from the obvious siblings list_shipment_routes and get_shipment. Purpose is inferable but not sharply articulated.

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?

There is no when-to-use guidance, no exclusion (e.g. 'use list_shipment_routes to enumerate segments'), and no mention of prerequisites such as needing both IDs to already exist. The only routing hint comes from the schema descriptions referencing list_shipment_routes and list_shipments, which is structured data, not the description's contribution.

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