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

With no annotations, the description carries the full burden and does disclose notable traits: pricing ($0.001/call), the x402/USDC-on-Base payment path, and that responses include a provenance chain and Ed25519 attestation. It stops short of failure modes or rate limits, but the payment/trust disclosure is well beyond what structured fields give.

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?

Two tightly packed sentences with no waste; the core purpose is front-loaded, followed by the payment/response context. Every clause earns its place.

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?

No output schema and no annotations, so the description should do more. It hints at response contents (vintage, series, provenance, attestation) but never describes the actual return fields or the id's format, leaving gaps for a data-lookup tool.

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 50%: payment is documented in-schema, but `id` is not. The description partially compensates by implying the id spans a state plus 'vintage and series identifiers,' giving the agent a clue about the 4-character id's composition, though not its exact syntax.

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+resource: 'US Census Bureau population estimate for one state,' which clearly identifies what data is returned. It doesn't explicitly name or differentiate against the closest sibling (state_gdp_series) or other state-level lookups, but the resource is unambiguous.

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?

No when-to-use guidance, no alternatives named, and no exclusions. The agent must infer from the name alone that this is the population dataset versus e.g. state_gdp_series.

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