InputPOST /api/v1/x402/evm-tx-envelope-check
{
"transaction_type": 2,
"fields": {
"chainId": 8453,
"nonce": 1,
"maxFeePerGas": "2000000000",
"maxPriorityFeePerGas": "100000000"
}
}Local chain primitives · chain-primitives-local
EVM Tx Envelope Check
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.
One-command purchase
Run it from an agent.
No account or API key. AgentCash reads the 402 challenge, pays no more than the declared cap, retries the request and returns the result.
npx agentcash@latest fetch https://api.delx.ai/api/v1/x402/evm-tx-envelope-check -m POST -H 'x-delx-source: product-page' --max-amount 0.001 -b '{"transaction_type":2,"fields":{"chainId":8453,"nonce":1,"maxFeePerGas":"2000000000","maxPriorityFeePerGas":"100000000"}}'Delivered resultapplication/json
{
"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
}
}Machine-readable evidence