{
  "format": "delx/intent-card/v1",
  "id": "evm-tx-envelope-check-api",
  "intent": "EVM Tx Envelope Check for an agent workflow",
  "title": "EVM Tx Envelope Check API for agents",
  "description": "EVM Tx Envelope Check: EVM Tx Envelope Check checks required envelope fields for a declared transaction type from bounded caller-supplied values without an external provider. Call EVM Tx Envelope Check before signing, submitting, replacing, or accepting an EVM/Base transaction assembled from caller-owned data. Returns normalized transaction evidence, calculated budget or shape findings, and a fail-closed preflight status for EVM Tx Envelope Check as versioned deterministic JSON. Price: $0.001 USDC via x402 on Base. First-party, stateless, memory-only execution with no paid upstream, live RPC, web search, credentials, custody, signing, media generator, or input retention. Honest limit: Uses caller-supplied values only; it performs no RPC call, signing, broadcasting, balance lookup, custody, trading, or live-chain claim. Advisory output only; the buyer owns authorization, payment policy, and production decisions.",
  "keywords": [
    "EVM Tx Envelope Check API",
    "EVM Tx Envelope Check for agents",
    "pay per result API",
    "x402 API",
    "no API key"
  ],
  "updated_at": "2026-08-23",
  "canonical_url": "https://commerce.delx.ai/intents/evm-tx-envelope-check-api",
  "machine_url": "https://commerce.delx.ai/intents/evm-tx-envelope-check-api.json",
  "recommendation": {
    "tool_name": "util_evm_tx_envelope_check",
    "service_name": "EVM Tx Envelope Check",
    "method": "POST",
    "resource": "https://api.delx.ai/api/v1/x402/evm-tx-envelope-check",
    "price_usdc": "0.001",
    "payment_protocols": [
      "x402",
      "mpp"
    ],
    "input_schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "type": "object",
      "properties": {
        "transaction_type": {
          "type": "integer",
          "description": "Transaction Type supplied to EVM Tx Envelope Check; used only for this bounded calculation and processed in memory without retention."
        },
        "fields": {
          "type": "object",
          "maxProperties": 128,
          "additionalProperties": true,
          "description": "Fields supplied to EVM Tx Envelope Check; used only for this bounded calculation and processed in memory without retention."
        }
      },
      "required": [
        "transaction_type",
        "fields"
      ],
      "additionalProperties": false
    },
    "example_input": {
      "transaction_type": 2,
      "fields": {
        "chainId": 8453,
        "nonce": 1,
        "maxFeePerGas": "2000000000",
        "maxPriorityFeePerGas": "100000000"
      }
    },
    "example_output": {
      "schema": "delx/util-evm-tx-envelope-check/v1",
      "operation": "evm_preflight:evm_tx_envelope_check",
      "status": "pass",
      "result": {
        "transaction_type": 2,
        "required_fields": [
          "chainId",
          "maxFeePerGas",
          "maxPriorityFeePerGas",
          "nonce"
        ],
        "missing_fields": [],
        "valid": true
      },
      "evidence": {
        "input_sha256": "847b54b0f549ee1ab246ef64c6b6670897f880fa285f91e0f08548bfdd9814d7",
        "retained": false,
        "external_calls": 0
      }
    },
    "agentcash": {
      "buy": "npx agentcash@latest fetch https://api.delx.ai/api/v1/x402/evm-tx-envelope-check -m POST -H 'x-delx-source: intent-card-evm-tx-envelope-check-api' --max-amount 0.001 -b '{\"transaction_type\":2,\"fields\":{\"chainId\":8453,\"nonce\":1,\"maxFeePerGas\":\"2000000000\",\"maxPriorityFeePerGas\":\"100000000\"}}'",
      "max_amount_usdc": "0.001"
    }
  },
  "attribution": {
    "header": "x-delx-source",
    "value": "intent-card-evm-tx-envelope-check-api"
  },
  "evidence": {
    "paid_openapi": "https://api.delx.ai/openapi.x402.json",
    "governed_portfolio": "https://api.delx.ai/x402-portfolio.json",
    "live_contract": "https://api.delx.ai/api/v1/x402/evm-tx-envelope-check"
  }
}