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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description goes well beyond them: it discloses the rejection rule ('work that adds neither changes nothing and is rejected'), the side effect that net book value and remaining life re-base from occurred_on, the invariant that purchase_date is NEVER changed, and the required asset_betterments:write scope.

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?

The work-defining scope, required fields, and the crucial never-change-purchase_date rule are front-loaded, and every subsequent sentence carries distinct information (rejection rule, alternatives, prerequisite, scope). No filler despite the density.

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 9-parameter mutation with no output schema, the description covers what the tool does, the field requirements, the behavioral consequences, the sibling routing, and the auth scope. Nothing an agent needs to invoke it correctly is missing.

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%, so the baseline is 3, but the description adds real constraint meaning absent from the schema: it specifies the 'at least one of capitalized_amount or added_life_years' requirement and clarifies occurred_on means the in-service date, not the invoice date. This is meaningful supplementation above the schema.

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 names a specific verb and resource ('Record capital work') and gives three concrete examples (elevator modernization, boiler retube, component replacement). It explicitly distinguishes this from sibling tools asset_lifecycle_events and condition assessments, so an agent can route correctly 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 states when to use this ('capital work that ALREADY extended a facility asset's life'), when not to ('work expected in future' -> lifecycle events; 'what someone observed' -> condition assessment), and a prerequisite step ('Call list_assets first to resolve asset_id'). This is explicit routing guidance with named alternatives.

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