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

Annotations only declare not-read-only, idempotent, closed-world; the description adds substantial context beyond that: the part is rendered from parametric source and sliced, the returned fields (quote_id, size, grams, price via USPS Ground Advantage, order_url), and the +$3 multicolor surcharge with both filaments used. The claim 'PLA only' is ambiguous and sits awkwardly against the schema's documented PETG option, which weakens confidence but is not an annotation conflict.

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 core purpose and return fields are correctly front-loaded, but the body is a dense run of semicolon-chained clauses mixing pricing, two-color mechanics, and downstream checkout instructions. The blanket 'PLA only' statement also costs clarity against the material enum, so a reader must reconcile conflicting signals.

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?

With no output schema, the description usefully enumerates the return fields and the downstream quote_id workflow, which is exactly what an agent needs. Remaining gaps are edge-case behavior (invalid values, whether qty affects slicing) and the unresolved PLA-vs-PETG statement.

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 baseline is 3; the description goes further by explaining the color/accent relationship (accent = text or pointer color, must differ from color, omitted for one-color lowest price) and gives a worked values example that the schema only gestures at. The one gap is that 'PLA only' muddies the material parameter that the schema documents at length.

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 ('Price a catalog item with the customer's values') and immediately anchors it to a concrete example with slug and values. It is clearly distinct from price_quote/quote_file, which operate on an existing quote or uploaded file rather than a catalog part.

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 routes the agent downstream: 'Then use price_quote or create_checkout with that quote_id, like any quote', and gives the exact handoff instruction for checkout ('pass the same color and options {"extraColors": [accent]}'). It also gives the accent rule ('leave out for one color (the lowest price)'). It does not explicitly state when to prefer this over quote_file, though the catalog-vs-file split is strongly implied.

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