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

Beyond readOnly/idempotent annotations, it discloses billing semantics (each accepted pair costs 1 call, invalid pairs not charged), partial-failure behavior (per-item error), and a plan-tier gate — all behavioral facts the annotations do not convey.

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?

Three tight sentences: identity/scope first, then cost and error semantics, then the access requirement. No filler and nothing buried.

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 an output schema present and full schema coverage, the description supplies exactly the missing pieces — equivalence to check_network, billing per pair, per-item error handling, and plan gating. Nothing needed to invoke it correctly is absent.

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% and the schema already documents npi format, plan_id formats, year defaults, and the 1–100 item bound. The description adds no parameter-level detail beyond what structured fields provide, so baseline 3 applies.

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 resource and scope ('the check_network answer for up to 100 (npi, plan_id) pairs in one request') and explicitly ties itself to the sibling check_network, so the agent can tell batch from single lookup immediately.

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 makes the batch context clear ('up to 100 ... in one request') and adds a hard prerequisite ('Needs the Builder plan or higher'). It stops short of explicitly saying 'use check_network instead for a single pair', but the relationship is strongly implied.

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