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 covered. The description goes beyond that by disclosing the returned shape (measure, year, target_value or target_statement) and the unit semantics 'in the measure's own unit, not money', which is meaningful behavior since there is no output schema.

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 dense sentence that front-loads the verb/resource and packs return details without filler. The parenthetical is slightly heavy but every clause carries information.

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?

With no output schema, the description usefully names the fields returned, and annotations carry the safety profile. For a simple one-param read tool this is essentially complete, though it omits any note on what happens when the ID is not found.

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?

Only one parameter (id, a uuid) with 100% schema description coverage, so the schema already documents it fully. The description's 'by ID' is redundant with the schema, and the unit note refers to a returned field rather than an input, so 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 (Get) and resource (LoS proposed target) scoped to a single record by ID, which implicitly separates it from list_los_proposed_targets. It doesn't explicitly name a sibling or contrast against get_los_measure/get_los_measurement, but the resource is unambiguous.

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 prerequisites, and no mention of the list_/update_/delete_ alternatives in the same family. An agent can infer retrieval-by-ID, but nothing steers it between this tool and its siblings.

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