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

Beyond the annotations (readOnlyHint=false, idempotentHint=true), the description discloses cost behavior (consumes one estimate credit), refusal conditions, refund on failed provider runs, and the non-destructive guarantee that existing review work cannot be overwritten. This is exactly the operational context an agent needs before spending credits.

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?

Information-dense and front-loaded: the primary action leads, followed by prerequisites, cost, and safety behavior. Four sentences all carry load, though the failure/refund clause could be tightened.

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?

An output schema exists so return structure need not be explained, yet the description still sets expectations ('extracted quantities for review, not a bid-ready estimate'). Combined with credit, idempotency, and non-destructiveness notes, an agent has everything needed to call this safely.

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 0%, so the description must carry parameter meaning. It defines confirm_credit_use ('refused unless true') and idempotency_key ('repeating a call with the same key does not charge again') well; project_id is only implied by the surrounding prose rather than explained.

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 specific verb and resource (initial AI takeoff for a new project) and pins down the exact precondition (plan PDF attached via attach_plan_pdf or uploaded in Portravo). It is easily distinguished from siblings like get_takeoff or attach_plan_pdf without opening any 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 explicitly names the prerequisite step (attach_plan_pdf or a user upload) and the gate (confirm_credit_use must be true), and warns that repeated idempotency keys do not re-charge. It gives clear context for when to call, though it does not explicitly contrast with get_takeoff for retrieving an existing takeoff.

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