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

Adds substantial behavior beyond the annotations: cost is $0.01 per call, payment is via x402 (USDC on Base) in _meta["x402/payment"] or MPP on the HTTP URL, and crucially an empty result set is still a paid 200. The 'up to 10 entities' cap and the exclusions (no officers, no street lines) further set expectations about payload content.

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?

Dense but nearly every clause carries load. Minor weakness in front-loading: the pricing/payment sentence leads before the tool's actual function, which delays the purpose statement, and the x402/MPP jargon is unexplained.

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 already present, the description covers the remaining unknowns an agent needs: cost, payment mechanism, accepted states, input identity requirements, result cap, and empty-result billing. Nothing essential for correct invocation is missing.

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 compensate: it clarifies the matching mode is 'exact name', distinguishes name vs entity number lookup paths, and the 10-entity cap implies name searches can match multiple records. It does not explain format constraints for entity_number beyond the schema example, keeping it below a 5.

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: returns a state business-registry record (status, formation, registered agent) by entity number or exact name. That is clearly distinct from siblings like license_search, nonprofit_verify, or carrier_lookup, though it never names those siblings explicitly to route the agent.

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 usable context: only six states are served (CO, CT, FL, IA, NY, OR), lookup requires entity number or exact name, results cap at 10, and the record excludes officers and street lines. It does not explicitly say when to prefer a sibling tool instead, so it stops short of a 5.

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