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 safety is fully covered. The description adds nothing behavioral beyond this – no note on error behavior for a missing ID, and no statement of what is returned. With annotations carrying the profile, this leaves the description with essentially zero added behavioral 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?

A single short sentence with no filler and the lookup key front-loaded. It is efficient, though so terse that it borders on under-specification rather than true conciseness.

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 trivial, single-parameter getter with a fully documented schema and annotations covering the safety profile, the description is minimally sufficient. It lacks any sibling disambiguation and gives no hint about failure modes or return shape, which is the remaining gap.

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%: the single 'id' parameter is documented as the 'Purchase order link ID' with uuid format. The description's 'by ID' repeats what the schema already states, so the baseline 3 applies with no added semantics.

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 ('Get one purchase order link'), and 'one ... by ID' does hint that it is a single-record fetch rather than a list. However, it largely restates the name and title, and never contrasts itself with the sibling list_purchase_order_links or get_purchase_order, which an agent needs to disambiguate.

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 guidance on when to use this tool versus list_purchase_order_links (browse/multi-record) or get_purchase_order (parent record). The agent must infer the selection rule purely from the name.

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