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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the description correctly aligns with those. It adds useful behavioral context beyond annotations by disclosing the cost ($0.005 USDC) and the fact that it aggregates 8-10 parallel sources, which helps an agent anticipate side effects and performance. It does not detail error handling or response schema, but the listed output contents provide a reasonable picture.

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 description is exceptionally concise, consisting of two terse sentences. The first sentence establishes the tool's purpose, and the second enumerates the data points and cost. Every phrase earns its place, with no filler or redundancy, making it easy for an agent to parse quickly.

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 one parameter, no output schema, and supportive annotations, the description covers the essential aspects: what the tool does, what data it returns, the cost, and the number of sources. It is sufficiently complete for a read-only bundle tool, though it omits potential error conditions or response format details, which are not critical given the simple profile.

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?

The input schema fully documents the 'wallet' parameter with a clear description ('EVM 0x… address (40 hex) or Solana base58 pubkey'), giving 100% schema description coverage. The tool description itself adds no additional parameter-level meaning, so the baseline score of 3 is appropriate.

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?

The description clearly states the tool's function as a 'Unified wallet intelligence bundle' and enumerates the exact data it returns: balances across Base, Ethereum, and Solana, USDC, tx counts, ENS/SNS reverse lookups, and a sanctions verdict. This specific verb-like framing ('ONE call' + list of outputs) distinguishes it from sibling tools like investigate_wallet or screen_wallet by positioning it as an aggregated one-shot intelligence bundle.

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 'ONE call' phrase implies the tool is meant for a comprehensive wallet intelligence lookup in a single request, which provides clear context. However, it does not explicitly state when to use this over alternatives (e.g., investigate_wallet) or when not to use it, so guidance is implied rather than explicit.

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