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

Consistent with readOnlyHint=true and adds context annotations cannot carry: the 20-record / 30-day cap, the contents of each record (returned services and prices, excluded services with reason, calculation memory when available), and the operator-configured app link prerequisite for source=wix. The epistemic caveat about absent records is exactly the kind of behavioral nuance an agent needs.

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?

Four dense sentences, front-loaded with the read-only scope and purpose, then branching logic, then record contents, then limits and caveats. No filler and nothing repeated from the schema or annotations.

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 and two optional parameters, the description supplies everything needed: what is returned per record, how many records, over what window, what the tool will not do, and the auth precondition. An agent can decide and call correctly from this text alone.

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 description coverage is 0%, so the description must carry the load; it explains supportCode's provenance, format role (identifies one quote) and default behavior when omitted, plus the source=wix prerequisite. The other enum value (mcp) and the default for source are left implicit, which is the only remaining gap.

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 (read-only lookup of this store's recent quotes) and names the concrete investigation goals it serves: unexpected price, missing service, empty quote. It is clearly separable from sibling diagnose_contract_issue / diagnose_label_issue and from get_shipping_rates, which is referenced as the origin of supportCode.

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 explicit routing: with a supportCode from get_shipping_rates it shows that single quote; without one it lists up to 20 quotes from the last 30 days. It also states the exclusion conditions – it does not re-run the quote or confirm the checkout price, and a missing record does not prove the quote never happened.

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