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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description adds real behavioral content by disclosing the price composition and the non-obvious quote_required return path. It stops short of stating currency, whether the figure is a unit or total price, or any tax handling, which are the remaining behavioral unknowns.

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?

Two tight sentences with no filler; the price composition and the escalation rule are both front-loaded before any reader would need them. Nothing is wasted.

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 three-parameter read-only pricing tool with no output schema, the definition covers what is priced, what is excluded, and the fallback path, which is enough to call it correctly. The only gap is that the shape of a successful return (currency, unit vs total) is not hinted at, which matters slightly more given there is no 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 67% and design_id/design_version are already documented there. The description adds no meaning to qty beyond loosely implying quantity, and does not explain the design_version linkage or what happens with an unknown version. Baseline 3 is appropriate given the schema carries most of the load.

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?

Names the specific resource (posted price) and precisely scopes what it covers: cups plus art prep fee, explicitly excluding shipping. An agent can tell immediately this is the self-serve pricing lookup and not the custom-quote path.

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 names the escalation condition (quantity of 50 or more, full wraps, business accounts) and the alternative to use in that case (request_quote), including the quote_required signal that triggers the switch. This is exactly the routing information an agent needs.

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