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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real behavioral context beyond them: the 10-record cap per call, the exact cost ($0.002 USDC via x402 across Base/Solana/Arc), and that failed calls are not charged — material for an agent deciding to invoke a paid tool.

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 compact sentences with zero filler: scope first, then match semantics, then the cap and price. Every sentence carries information the agent needs and nothing is 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?

Output schema exists so return values need no explanation, annotations cover the safety profile, schema covers parameters, and the description fills the remaining gaps an agent needs — result cap, fuzziness caveat, and paid-call economics with failure exemption.

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 100%, so all four parameters (last_name, first_name, state, max) are already fully documented in the schema. The description adds nothing parameter-level, which is the expected baseline when the schema does the heavy lifting.

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 ('search') against a named authoritative source (CMS NPPES NPI Registry) and enumerates the returned fields (NPI, name, credential, status, taxonomy, practice location). An agent can distinguish this from physician_compare_cms or state_medical_board tools by the NPPES source, though it never explicitly contrasts itself with those siblings.

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 mention that 'matches can be fuzzy; the registry decides the match' implies a name-based lookup context, but there is no explicit when-to-use, when-not-to-use, or named alternative among the many physician/medical-board siblings. Usage is inferable rather than stated.

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