Produce or validate an EIP-55 checksummed EVM address without network calls — call when producing or checking EIP-55 checksum addresses. Use for chain input hygiene without live RPC—adjacent to OneSource-class small chain reads, but static/local only so rights and margin stay clear. Returns deterministic machine-readable JSON for $0.003 USDC via x402 on Base. Execution is first-party, local-only, stateless, and memory-only with no paid upstream, no input retention, and no claim of live chain tip, web search, or media generation. Results are advisory; the caller owns authorization and production controls.