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

Annotations already flag a non-read-only, open-world operation, and the description adds real substance: it reads material and thickness from the CAD, hits live supplier offers, reports missing prices/blockers, and only writes a draft with no charge or checkout. Remaining gaps are minor — no mention of whether the draft persists, how long a live-quote lookup takes, or failure modes.

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 purpose is front-loaded in the first sentence, followed by what the server does, then the no-side-effects disclaimer, then the auth caveat. Every sentence adds new information; none restates the name or title.

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 5-parameter tool with full schema coverage and an output schema, the description covers what an agent needs: scope (whole assembly), mechanism (CAD reads + live supplier lookup), side-effect boundary, and auth requirements. Return-value detail is correctly left to the output schema.

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 meaning the schema doesn't: materials and sheet thickness come from CAD rather than from `params`, and `projectSlug` use requires sign-in while source/public projects can be estimated as a guest. That clarifies parameter choice beyond the field-level text.

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 gives a specific verb+resource ("Prepare an indicative estimate and durable manufacturing checklist for a whole CAD assembly") and scopes it with mixed materials/processes. It also implicitly separates this tool from ordering siblings by stating it does not send an order, charge, or start checkout.

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 clearly establishes when this tool fits (a whole assembly, mixed materials, wanting a draft estimate plus blockers) and when it doesn't (ordering/checkout). What it lacks is naming the actual alternatives — e.g. order_part, request_assembly_quote, price_part, dfm_review — so an agent must infer sibling routing from the tool list.

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