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

Annotations already flag a non-idempotent, open-world, destructive write; the description adds non-obvious context on top: customer PII is transmitted to Renzy, a quote email is sent, no card is collected or charged, the response carries a photo-upload link, and duplicate calls create duplicate orders. That last point directly explains the idempotentHint=false constraint in operational terms.

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 critical constraints are front-loaded (what it does, what to confirm first) and the caveats follow in short declarative sentences. Slightly long for a simple order primitive, but every sentence conveys a constraint an agent could otherwise get wrong.

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 13-parameter, nested-object mutation with no output schema, it covers the important ground: data sent, email side effect, no payment, duplicate-order hazard, and one return element. It leaves the rest of the response shape (order id, total, status) and failure handling unspecified.

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 provenance meaning: answers come from the priced quote result, package_id is the chosen option, install_date must be one of the quoted dates, and extras are among what gets confirmed with the customer. It stops short of explaining formats for address fields or what the answers object must contain.

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 ('Order a fixed-price installation') and scopes it by origin ('priced by quote_installation') and by the date source ('on one of its installation dates'), which cleanly separates it from quote_installation (pricing) and book_plumber (a different trade).

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?

Gives a clear prerequisite ('priced by quote_installation') and a pre-call confirmation ritual covering option, extras, total, date and address, plus an explicit do-not-retry rule. It never explicitly names when to prefer book_plumber or check_availability, so routing against those siblings is left implicit.

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