decode_tx

Instructions

Implementation Reference

• index.js:122-134 (schema)

  Tool definition and inputSchema for 'decode_tx'. Defines the tool name, description, and input schema requiring 'chain' (enum: base, ethereum, solana) and 'tx_hash' (string).

  {
    name: "decode_tx",
    description:
      "Structured decode of any mainnet transaction by hash. Supply chain ('base' | 'ethereum' | 'solana') and tx_hash. Returns from/to/value/gas/status/calldata for EVM, or slot/fee/signers/program_calls for Solana. Mined txs cached in-process. Use for tx inspection, audit, agent UX (rendering tx summaries to users). $0.001 USDC.",
    inputSchema: {
      type: "object",
      properties: {
        chain: { type: "string", enum: ["base", "ethereum", "solana"] },
        tx_hash: { type: "string", description: "EVM 0x+64hex or Solana base58 signature." },
      },
      required: ["chain", "tx_hash"],
    },
  },

• index.js:68-200 (registration)

  The TOOLS array containing all 9 tool definitions including 'decode_tx'. This array is registered via ListToolsRequestSchema handler.

  const TOOLS = [
    {
      name: "anchor_hash",
      description:
        "Anchor a 32-byte hash to BOTH Base mainnet (as EIP-1559 calldata) and Solana mainnet (via the Memo program) in a single call. Returns both transaction hashes plus block-explorer URLs as cryptographic proof of when the hash existed. Pure infrastructure — no opinions about content. Use for DAO vote receipts, AI decision attestations, contract notarization, scientific data integrity, audit trails. $0.005 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          hash: {
            type: "string",
            description: "Pre-computed 32-byte hex hash (64 chars, no 0x prefix). Mutually exclusive with `data`.",
          },
          data: {
            description: "Arbitrary JSON to be canonicalized + SHA-256'd by the server. Mutually exclusive with `hash`.",
          },
          note: {
            type: "string",
            description: "Optional 200-char note included in the response (NOT on-chain).",
          },
        },
      },
    },
    {
      name: "screen_wallet",
      description:
        "Sanctions + AML screening for any EVM or Solana wallet address. Returns sanctions match (boolean), specific OFAC SDN programs flagged (Tornado Cash, Lazarus Group, Hydra Market, Garantex, Blender.io etc.), inferred chain, and a low/medium/high risk verdict. Use for AML pre-flight checks before any treasury transfer, KYC onboarding, vendor diligence, payroll wallet verification, marketplace counterparty checks. $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          wallet: {
            type: "string",
            description: "EVM 0x… address (40 hex) or Solana base58 pubkey.",
          },
        },
        required: ["wallet"],
      },
    },
    {
      name: "attest_decision",
      description:
        "Verify a wallet signature over (input_hash, output_hash, decision) with domain separation, then dual-chain anchor the resulting Merkle root on Base and Solana mainnet. Returns the verified signer plus on-chain proof URLs. Use when an AI agent's decision needs a cryptographic, auditable receipt — autonomous trade approvals, AI-assisted contract decisions, model-output attestation for liability records. $0.010 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          input_hash: { type: "string", description: "64-char hex SHA-256 of the agent's input." },
          output_hash: { type: "string", description: "64-char hex SHA-256 of the agent's output / decision payload." },
          decision: { type: "string", description: 'Free-form short label, e.g. "APPROVED", "REJECTED", "CONFIDENCE=0.93" (max 64 chars).' },
          scheme: { type: "string", enum: ["eip191", "ed25519"], description: "Signature scheme." },
          signature: { type: "string", description: "0x-prefixed hex (eip191) or base58 (ed25519)." },
          signer_pubkey: { type: "string", description: "Required for ed25519 (Solana base58 pubkey)." },
        },
        required: ["input_hash", "output_hash", "decision", "scheme", "signature"],
      },
    },
    {
      name: "decode_tx",
      description:
        "Structured decode of any mainnet transaction by hash. Supply chain ('base' | 'ethereum' | 'solana') and tx_hash. Returns from/to/value/gas/status/calldata for EVM, or slot/fee/signers/program_calls for Solana. Mined txs cached in-process. Use for tx inspection, audit, agent UX (rendering tx summaries to users). $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          chain: { type: "string", enum: ["base", "ethereum", "solana"] },
          tx_hash: { type: "string", description: "EVM 0x+64hex or Solana base58 signature." },
        },
        required: ["chain", "tx_hash"],
      },
    },
    {
      name: "resolve_name",
      description:
        "Cross-chain name resolution. Pass a name like 'vitalik.eth' or 'bonfida.sol' and get back the resolved address(es) across supported registries. Currently supports ENS (.eth) and Bonfida SNS (.sol). Cached 1h server-side. $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          name: { type: "string", description: "Human-readable name, e.g. 'vitalik.eth' or 'bonfida.sol'." },
        },
        required: ["name"],
      },
    },
    {
      name: "token_price",
      description:
        "USD spot price for any major token. Pass either `symbol` (BTC, ETH, SOL, USDC, etc.) OR (chain + contract). Returns USD price, 24h change percent, market cap, fetched-at timestamp. CoinGecko-backed, cached 60s. $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          symbol: { type: "string", description: "Token symbol like 'ETH'. Mutually exclusive with chain+contract." },
          chain: { type: "string", description: "Chain slug: base, ethereum, solana, polygon, arbitrum, optimism, bsc, avalanche." },
          contract: { type: "string", description: "Token contract address. Required with chain." },
        },
      },
    },
    {
      name: "decode_calldata",
      description:
        "Decode raw EVM calldata into a human-readable function name, canonical signature, and typed parameter values. Resolves the 4-byte selector against openchain.xyz's signature directory, then ABI-decodes the args. Use for tx inspection before signing, mempool analysis, debug. EVM-only (chain='ethereum'); 'solana' returns 400. $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          chain: { type: "string", enum: ["ethereum", "solana"], description: "EVM-only; 'solana' returns 400." },
          calldata_hex: { type: "string", description: "Raw EVM calldata (>=4 byte selector), with or without 0x prefix." },
          contract_address: { type: "string", description: "Optional. Reserved for future on-chain ABI lookups." },
        },
        required: ["chain", "calldata_hex"],
      },
    },
    {
      name: "parse_datetime",
      description:
        "Parse any freeform datetime string ('tomorrow at noon', 'yesterday', '2026-05-13T15:30Z', 'in 2 hours') into a fully structured normalized form: ISO 8601, unix epoch, components (year/month/day/hour/min/sec/weekday), relative seconds + human form, confidence score. Saves agent LLM tokens on date parsing. $0.001 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          input: { type: "string", description: "Freeform datetime string." },
          base_time: { type: "string", description: "Optional ISO 8601 reference; defaults to now UTC." },
          timezone: { type: "string", description: "Optional IANA tz name (e.g. 'America/New_York'); defaults to UTC." },
        },
        required: ["input"],
      },
    },
    {
      name: "intel_wallet",
      description:
        "Unified wallet intelligence bundle. ONE call returns balances on Base + Ethereum + Solana, USDC across chains, transaction count, ENS/SNS reverse lookup, and sanctions verdict — all aggregated from 8–10 parallel free public sources. Replaces a wallet-investigation script with a single $0.005 call. Use for KYB pre-flight, counterparty research, fraud detection. $0.005 USDC.",
      inputSchema: {
        type: "object",
        properties: {
          wallet: { type: "string", description: "EVM 0x… address (40 hex) or Solana base58 pubkey." },
        },
        required: ["wallet"],
      },
    },
  ];

• index.js:242-250 (handler)

  Handler case in buildRequest() for 'decode_tx'. Constructs a POST request to `${BASE_URL}/v1/decode/tx` with JSON body containing chain and tx_hash arguments.

  case "decode_tx":
    return {
      url: `${BASE_URL}/v1/decode/tx`,
      opts: {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ chain: args.chain, tx_hash: args.tx_hash }),
      },
    };

• index.js:302-343 (helper)

  The CallToolRequestSchema handler that invokes buildRequest() and executes the paidFetch call for all tools including 'decode_tx'.

  server.setRequestHandler(CallToolRequestSchema, async (request) => {
    const { name, arguments: args = {} } = request.params;
    let req;
    try {
      req = buildRequest(name, args);
    } catch (err) {
      return {
        content: [{ type: "text", text: `Error: ${err.message}` }],
        isError: true,
      };
    }
  
    try {
      const res = await paidFetch(req.url, req.opts);
  
      if (res.status === 402) {
        const body = await res.text().catch(() => "");
        const msg = paymentEnabled
          ? `Payment failed (402). The wallet may be out of USDC on Base, or the x402 facilitator rejected the payload.\n\nResponse body: ${body.slice(0, 300)}`
          : `Payment required (402). Set ANCHOR_WALLET_PRIVATE_KEY in your MCP config so this server can pay automatically:\n\n  "env": {\n    "ANCHOR_WALLET_PRIVATE_KEY": "0xYOUR_BASE_WALLET_PRIVATE_KEY"\n  }\n\nFund the wallet with USDC on Base (any amount > $0.05 is plenty). The wallet pays $0.001–$0.010 per call.\n\nResponse body: ${body.slice(0, 300)}`;
        return { content: [{ type: "text", text: msg }], isError: true };
      }
  
      if (!res.ok) {
        const body = await res.text().catch(() => "");
        return {
          content: [{ type: "text", text: `anchor-x402 returned ${res.status}: ${body.slice(0, 500)}` }],
          isError: true,
        };
      }
  
      const data = await res.json();
      return {
        content: [{ type: "text", text: JSON.stringify(data, null, 2) }],
      };
    } catch (err) {
      return {
        content: [{ type: "text", text: `anchor-x402 request failed: ${err.message}` }],
        isError: true,
      };
    }
  });