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

Goes well beyond the annotations by disclosing pricing ($0.01/call via x402 or card key, first 25 free, failed calls free) and that 'each call is charged, so repeats are not free' – which meaningfully explains the idempotentHint=false flag. It restates the read-only nature ('reads or computes only and changes nothing'), which is redundant with readOnlyHint but harmless. It does not describe latency, rate limits, or partial-failure behavior across the five chains.

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-loads the capability, then usage, then pricing/constraints – a sensible order with no filler. It is dense and slightly long, with the pricing clause spanning a full sentence, but each part carries actionable information.

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 exists, yet the description enumerates the returned data categories (balances per chain, tx counts, contract status, USDC transfers, sanctions result), so an agent knows what it gets back. Combined with cost and side-effect disclosure, 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?

With one parameter at 100% schema coverage the baseline is 3, but the description adds value by qualifying the address as an 'EVM wallet' and supplying a concrete example address, reinforcing the expected 0x format and that only EVM networks are supported.

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?

Opens with a specific verb+resource ('One call to profile an EVM wallet') and enumerates exactly what the profile contains: native/USDC balances across five chains, tx counts, contract-vs-wallet, recent USDC transfers, OFAC screen. This makes it clearly distinguishable from granular siblings like base_balance or sanctions_check.

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?

Explicitly states when to use it ('before paying, onboarding or trusting a counterparty wallet') and names the alternative for a different need ('for a single risk verdict use check_counterparty'). Also positions it as a bundle ('cheaper than the tools bought one by one'), giving the agent a cost-based selection rule.

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