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

Annotations cover the safety profile (readOnly, idempotent, non-destructive), and the description adds genuinely new operational facts: outgoing-only counting semantics, archive rather than 30-day sourcing, per-call pricing, the prepaid x-credit-token header, absence of a free tier, and no API key requirement.

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?

The headline outputs are front-loaded and each sentence carries real information (sourcing, counting rules, pricing, auth). There is mild redundancy between the opening fragment and the fuller restatement of the same three outputs, which slightly dilutes density.

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?

An output schema exists, so return values need no explanation, and the description still covers the non-obvious counting semantics, data sourcing, pricing, and auth requirements needed to call the tool correctly. Nothing material 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 100% for the single address parameter, so the schema already carries the parameter documentation and the baseline is 3. The description's "Required input: address" merely restates the schema's required field without adding format or validation detail.

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 set of outputs (wallet age in days, first/last activity timestamps, outgoing transaction count) for a Base address, which is concrete and unambiguous. It implicitly distinguishes itself from 30-day-feed tools and from base_nonce-style tools, but it never names a sibling to sharpen the boundary, keeping it below a 5.

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 clear intended use cases ("Built for sybil screening and counterparty trust checks"), so an agent knows the context in which to reach for it. It offers no explicit when-not guidance or named alternatives, which a 5 would require.

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