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

Goes well beyond the annotations: 'Orders and charges nothing' clarifies that non-readOnly creation carries no financial commitment, and it discloses the security-sensitive token handling ('keep it private and never show it to anyone') plus the fact that the token is scoped to this single order. It also previews what the caller will see back from the 3D model/cadastre and that customer corrections and open points are expected.

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?

Front-loaded with purpose and the precondition, and nearly every clause carries information. The third sentence is dense, packing return identifiers, token scope, privacy handling and model-derived content together, which slightly hurts scannability.

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 creation tool with an output schema and existing annotations, nothing an agent needs is missing: prerequisite source, cost behavior, token handling, and a summary of the returned estimates/open points are all covered.

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% and the single parameter is already documented, so the baseline is 3; the description adds real value by establishing provenance ('find_building returned') and the confirmation precondition, not just type information. It does not add format or validation details, hence 4 rather than 5.

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 and resource ('Starts a draft order') plus the exact scope ('for the building the user confirmed'), which cleanly separates it from siblings like update_order, review_order and find_building. An agent knows immediately this is the order-creation entry point.

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?

Explicitly ties invocation to a prior step: 'building_ref from find_building' for 'the building the user confirmed', so the prerequisite is unambiguous. It stops short of naming when not to use it or pointing to review_order/update_order for follow-up work, so it is clear context rather than full routing guidance.

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