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

Beyond the non-destructive/read-only annotations, the description discloses important behaviors: NY/NJ route to BioReference, Rhode Island is not served, the flat $6 fee, unorderable-item reasons, and the prefilled cart URL. This is substantive behavioral context that annotations alone do not provide.

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 description is dense but well-organized, front-loading the core action before listing the expected outputs and the usage mandate. Every clause adds value; there is no filler or redundant restatement of the tool name.

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 present, the description fully compensates by enumerating the return contents: per-lab prices, state routing, the fee, total, non-orderable items with reasons, and the prefilled cart URL. It also covers key edge cases such as NY/NJ routing and Rhode Island exclusion, making it complete for a quoting operation.

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. The description adds meaning beyond the schema by clarifying how `state` affects lab routing and that `lab` is the preferred lab outside NY/NJ. This helps the agent choose parameter values correctly without restating schema definitions.

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?

The description opens with a specific verb and resource: 'Price a set of tests/panels exactly as TestWell's checkout would'. It then enumerates the concrete outputs (per-lab prices, fee, total, unorderable items, cart URL), making the tool's role unmistakable and clearly distinct from siblings like compare_prices or search_tests.

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?

The description gives an explicit usage instruction: 'Use this before quoting any total to a user.' This clearly tells the agent when to invoke the tool. It does not explicitly name alternative tools or state when not to use it, so it stops short of full exclusion guidance.

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