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

With no annotations, the description carries the full burden and does so: it discloses that the response is booleans-only, that locked fields come back as null inside a `locked` map, that an `error` field appears when the agent is not indexed, and it flags two deprecated fields with explicit sunset dates (2026-11-07). That is well beyond what structured fields 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?

Front-loaded with the purpose, then a clean Args block, then returns, then the paid upsell. It is dense rather than padded, but the defaults are stated twice (in Args and again in the Example sentence), and the paid-counterpart paragraph is long relative to the free tool's behavior.

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?

There is no output schema, so the description must enumerate return fields — and it does, listing reachability, TLS validity, x402 support, the three payment booleans, MCP/OpenAPI counts, well-known presence, owner-named, and status_label_v2 values. Combined with the error-field and locked-map notes, an agent has everything needed to call it and interpret the result.

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 and it does fully: `chain` is documented as one of "base" or "ethereum" with default "base" (an enum constraint the schema lacks), and `agent_id` is described as the numeric ERC-8004 id defaulting to 19353 (Agent Zero). The worked example `{"chain": "base", "agent_id": 19353}` makes the call shape unambiguous.

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 — counts-only objective signals for one ERC-8004 agent — and immediately bounds scope with the explicit exclusion 'No owner identity string and no payment amounts — those are paid.' An agent can tell exactly what this returns versus the paid intel endpoint without any ambiguity.

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 a concrete usage directive ('Use this to vet a counterparty agent before transacting') and names the paid alternative with the condition that selects it (when you need trust_verdict, readiness_score, Sybil-adjusted reputation). It does not differentiate from the similarly named sibling agent_trust_teaser, which an agent could plausibly confuse with this tool, so it falls just 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.