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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds value beyond that by disclosing the required los_targets:write scope and the automatic direction-follows-metric behavior, plus the base_target scale constraint. It stops short of describing response or side effects on linked records.

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?

Four sentences, front-loaded with the core action, then the two operational caveats, then the scope requirement. Little waste, though the scale-constraint sentence is slightly dense and could be trimmed.

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 mutation tool with no output schema and full schema coverage, the description covers the essential gaps: authorization scope, parameter interaction, and metric-driven direction. It is complete enough to call correctly, though it omits whether the ID lookup path (list vs get) is expected first.

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?

With 100% schema coverage the baseline is 3, but the description goes further by explaining the cross-parameter interaction between metric and base_target — that changing to a smaller-scale metric requires resending base_target — which the schema's per-field descriptions don't capture. This adds genuine interpretive meaning.

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 uses a precise verb+resource ('Update a system LoS target by ID'), which cleanly distinguishes it from the sibling update_infrastructure_los_target, update_los_proposed_target, and the create/get/delete variants of the same resource. An agent can identify the operation and target entity 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?

It offers real operational guidance ('send a new base_target when changing to a metric with a smaller scale') but never states when to choose this tool over alternatives or that the ID must be resolved first. The usage context is implied by the update verb and the identified resource rather than spelled out.

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