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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is covered. The description adds genuinely useful behavior beyond that: 'Returns an empty order when none matches' tells the agent a miss is a non-error result rather than a 404 or exception, and the endpoint path confirms it is a direct single-record lookup.

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 compact sentences, front-loaded with the action and scope, then the edge-case return behavior, then the endpoint. Every clause carries information; nothing is padded.

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 no output schema, the description covers the key ambiguity (empty result on miss) and the identifier source. It does not describe the shape of a returned order, but sibling order tools and the API contract make that low-risk for a lookup by ID.

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 coverage is 100% with a single parameter, so the baseline is 3; the description earns slightly more by explaining where the value comes from ('the integer shown in the order book'), which helps an agent source the argument rather than just type it. It does not add format or validation detail beyond the schema's exclusiveMinimum/maximum constraints.

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 (find) and resource (one order) with the identifier type made explicit ('Linnworks order number'), and the scope phrase 'open or processed' separates it from the open-only siblings like linnworks_list_open_orders and linnworks_get_open_orders_details. It stops short of naming the closest alternative, linnworks_find_orders_by_reference, which is the main ambiguity an agent faces.

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 parenthetical '(the integer shown in the order book)' implies the precondition that the caller already holds a numeric order number, and the 'open or processed' scope hints at coverage. However, there is no explicit when-not statement and no pointer to linnworks_find_orders_by_reference for reference-based lookups, so routing between the two find-tools 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.