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

Adds real context beyond the readOnlyHint/openWorldHint annotations: zero cost, no side effects, and that validation failures return a list of problems to fix rather than erroring out. It does not discuss rate limits or quote expiry, which would round it out.

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 the core action and kept to two compact sentences. The long comma-chained enumeration of returned artifacts makes it denser than it needs to be, but every clause carries information.

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 takes on return-value disclosure and does so thoroughly: total, delivery estimate, quote_id, reserve_url, ESPHome config, plus the error shape. An agent knows both what it gets back and how failures surface.

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 all four parameters are already documented in the input schema. The description only obliquely reinforces them (VAT 'for the destination country' justifies country; 'built from catalog modules' frames parts) and says nothing about units or enclosure.

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+resource: prices a device built from catalog modules, and enumerates what the total covers (parts, enclosure, assembly, shipping, fee, VAT). It implicitly separates itself from catalog (module ids) and reserve (quote_id/reserve_url), but never names those siblings explicitly.

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?

Usage is only implied through the workflow hints — a quote_id for reserve and a reserve_url to open — plus the 'free, no side effects' note. It never says explicitly when to call this versus catalog or reserve, nor any prerequisites such as resolving module ids first.

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