Crypto RPC

Proxy a JSON-RPC request to a supported blockchain node and bill per credit.

Request shapes

• Single request: a JSON-RPC 2.0 object ({ "jsonrpc":"2.0", "method":"…", "params":[…], "id":1 }).
• Batch: an array of up to 100 JSON-RPC 2.0 objects. If any item references an unsupported method, the entire batch is rejected with 400 and the offending methods are listed.

Supported methods

Methods are classified into three pricing tiers:

• Standard (1×): eth_call, eth_getBalance, eth_blockNumber, eth_sendRawTransaction, eth_getLogs, net_version, web3_clientVersion, ERC-4337 bundler methods (eth_sendUserOperation, etc.), and chain-family extensions (zks_*, linea_*, bor_*, starknet_*).
• Advanced (2×): trace_*, debug_*, txpool_inspect, txpool_status, arbtrace_*.
• Large (4×): trace_replayBlockTransactions, trace_replayTransaction, txpool_content, arbtrace_replay*.

Stateful filter methods (eth_newFilter, eth_getFilterChanges, eth_uninstallFilter, etc.) are not supported — they break on a load-balanced HTTP proxy because filter state is pinned to a single upstream backend. Use eth_getLogs instead.

WebSocket-only methods (eth_subscribe, eth_unsubscribe) return 400 because this proxy is HTTP-only.

Pricing

Credits consumed per call = baseCredits[chain] × methodTier. baseCredits is 20 for most EVM chains (Ethereum, Base, Optimism, Arbitrum, Polygon, Linea, Avalanche, BSC, Blast) and Starknet; 30 for zkSync Era. The USD price per credit is ~7e-7 — a single standard EVM call costs ≈ $0.000014 and a large trace-replay costs ≈$0.000056.

Per-request errors at the JSON-RPC layer (HTTP 200 with an error field in a response item) are billed at 5 credits instead of the full method tier — a small concession for methods not supported on a given chain or bad-parameter responses.

Rate limits

Two caps apply per caller:

• Requests per minute: 100 on the paid tier, 1000 on the staff tier.
• Credits per rolling 24 hours: 10,000,000 on the paid tier, 100,000,000 on the staff tier. When either cap is exceeded, the request returns 429 with a customMessage identifying which cap tripped. The per-minute cap also sets the X-RateLimit-* response headers.

Idempotency

Set the Idempotency-Key request header to any string matching [A-Za-z0-9_-]{1,255} to enable safe retries. The response is cached for 24 hours keyed on (user, idempotency-key); replaying the same key with the same body returns the cached response with Idempotent-Replayed: true. Reusing the same key with a different body returns 400 to prevent silent corruption.

Authentication: This endpoint accepts either a Bearer API key or an X-Sign-In-With-X header for x402 wallet-based authentication. When using x402, a 402 Payment Required response indicates insufficient balance and includes top-up instructions.

POST /crypto/rpc/{network}

cURL

singleRequest

curl --request POST \ --url https://api.venice.ai/api/v1/crypto/rpc/{network} \ --header 'Authorization: Bearer <token>' \ --header 'Content-Type: application/json' \ --data ' { "jsonrpc": "2.0", "method": "eth_chainId", "params": [], "id": 1 } '

200

singleSuccess

{ "jsonrpc": "2.0", "id": 1, "result": "0x1" }

Forward a JSON-RPC 2.0 request (single or batch) to a supported blockchain node. Supports both API key and x402 wallet authentication. Billing is per credit and denominated in your Venice balance — one credential, one invoice, every chain below.

Authentication

This endpoint supports two authentication methods:

• API Key: Standard Bearer token authentication via the Authorization: Bearer <key> header.
• x402 Wallet: Pay-as-you-go with USDC credits from your Ethereum wallet — no Venice account required. See the x402 guide for setup.

Both methods share the same rate limits and billing (Venice credits).

Supported networks

See GET /crypto/rpc/networks for the live, authoritative list. Current coverage:

Family	Mainnet	Testnets
Ethereum	ethereum-mainnet	ethereum-sepolia, ethereum-holesky
Polygon	polygon-mainnet	polygon-amoy
Arbitrum	arbitrum-mainnet	arbitrum-sepolia
Optimism	optimism-mainnet	optimism-sepolia
Base	base-mainnet	base-sepolia
Linea	linea-mainnet	linea-sepolia
Avalanche C-Chain	avalanche-mainnet	avalanche-fuji
BNB Smart Chain	bsc-mainnet	bsc-testnet
Blast	blast-mainnet	blast-sepolia
zkSync Era	zksync-mainnet	zksync-sepolia
Starknet	starknet-mainnet	starknet-sepolia

Request shapes

Single request

{
  "jsonrpc": "2.0",
  "method": "eth_chainId",
  "params": [],
  "id": 1
}

Batch request

An array of up to 100 JSON-RPC 2.0 objects. Each item is validated independently; if any method is unsupported, the entire batch is rejected with 400 and every offending method name is listed in the error message.

[
  { "jsonrpc": "2.0", "method": "eth_chainId", "params": [], "id": 1 },
  { "jsonrpc": "2.0", "method": "eth_blockNumber", "params": [], "id": 2 }
]

Supported methods and pricing tiers

Methods are classified into three credit tiers. Credits consumed per call = baseCredits[chain] × methodTier.

Tier	Multiplier	Example methods
Standard	1×	eth_call, eth_getBalance, eth_blockNumber, eth_sendRawTransaction, eth_getLogs, eth_getTransactionReceipt, eth_estimateGas, net_version, web3_clientVersion, ERC-4337 bundler methods (eth_sendUserOperation, eth_estimateUserOperationGas, etc.), chain-family extensions (zks_*, linea_*, bor_*, starknet_*)
Advanced	2×	trace_block, trace_call, trace_transaction, debug_traceCall, debug_traceTransaction, debug_traceBlockByHash, txpool_inspect, txpool_status, arbtrace_*
Large	4×	trace_replayBlockTransactions, trace_replayTransaction, txpool_content, arbtrace_replayTransaction, arbtrace_replayBlockTransactions

Base credits per chain

baseCredits	Chains
20	Ethereum + all EVM L2s above (Base, Optimism, Arbitrum, Polygon, Linea, Avalanche, BSC, Blast) and Starknet
30	zkSync Era

Cost examples

At Venice’s ~$6.25 × 10⁻⁷ per credit:

Call	Credits	USD cost
eth_call on Ethereum (20 × 1×)	20	$0.0000125
trace_transaction on Ethereum (20 × 2×)	40	$0.0000250
trace_replayTransaction on Ethereum (20 × 4×)	80	$0.0000500
eth_call on zkSync (30 × 1×)	30	$0.0000188

Not supported

• WebSocket-only methods (eth_subscribe, eth_unsubscribe) — this proxy is HTTP-only. Poll instead, or upgrade to a direct WebSocket provider.
• Stateful filter methods (eth_newFilter, eth_getFilterChanges, eth_getFilterLogs, eth_uninstallFilter, eth_newBlockFilter, eth_newPendingTransactionFilter) — filter state is pinned to a single upstream backend and silently breaks on a load-balanced HTTP proxy. Use eth_getLogs (stateless) instead.
• Miner / key-holding methods (eth_sign, eth_accounts, eth_mining, eth_hashrate, eth_getWork, eth_submitWork) — hosted provider endpoints don’t hold user private keys, so these always error. Sign transactions client-side and submit via eth_sendRawTransaction.
• Unmapped methods — anything not explicitly allowlisted returns 400. Contact support to request additions.

Per-item batch billing

Even when the HTTP response is 200, individual batch items can come back with a JSON-RPC error field (for example, a bad-params error or a method not supported on the target chain). Venice bills these items at 5 credits each rather than the full method tier — a small concession for normal “exploring the API” mistakes.

// Batch request:
[
  { "jsonrpc": "2.0", "method": "eth_chainId",   "params": [],         "id": 1 },
  { "jsonrpc": "2.0", "method": "eth_getBalance","params": ["bad"],    "id": 2 }
]

// Response (HTTP 200, X-Venice-RPC-Credits: 25):
[
  { "jsonrpc": "2.0", "id": 1, "result": "0x1" },
  { "jsonrpc": "2.0", "id": 2, "error": { "code": -32602, "message": "invalid params" } }
]

The first item (success) bills 20 credits, the second (RPC-level error) bills 5, sum = 25.

Rate limits

Per-minute request cap per authenticated caller:

Tier	Requests/minute
Standard	100
Staff	1,000

When the cap is exceeded the endpoint returns 429 with a customMessage and standard X-RateLimit-* response headers.

Idempotency

Set the Idempotency-Key request header to any string matching [A-Za-z0-9_-]{1,255} to enable safe retries. The response is cached for 24 hours keyed on (user, idempotency-key):

• Replaying the same key with the same body returns the cached response and an Idempotent-Replayed: true response header. The upstream is not touched and no new credits are charged.
• Replaying the same key with a different body returns 400 to prevent silent state corruption. Pick a fresh key for distinct requests.

Response headers

Header	Description
X-Venice-RPC-Credits	Credits charged for this request. On batch requests, this is the sum across items.
X-Venice-RPC-Cost-USD	Dollar cost to 8 decimal places. Equal to X-Venice-RPC-Credits × price per credit.
X-Request-ID	32-character correlation ID. Include in any support correspondence.
Idempotent-Replayed	Present with value "true" when the response came from the idempotency cache.
X-RateLimit-Limit / X-RateLimit-Remaining / X-RateLimit-Reset	Set only on 429 responses.

Forensic logging for transaction relays

Every call to eth_sendRawTransaction is logged server-side with the tx hash (keccak256 of the raw bytes), the network slug, the request ID, and the calling user ID. We do not retain the signed payload itself — the hash is recoverable from the on-chain receipt. This audit trail exists so that if a customer’s API key is compromised and used to relay illicit transactions through our infrastructure, we can correlate on-chain activity back to the responsible account.

Example

curl https://api.venice.ai/api/v1/crypto/rpc/ethereum-mainnet \
  -H "Authorization: Bearer $VENICE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_chainId",
    "params": [],
    "id": 1
  }'

{ "jsonrpc": "2.0", "id": 1, "result": "0x1" }

Response headers: X-Venice-RPC-Credits: 20, X-Venice-RPC-Cost-USD: 0.00001250, X-Request-ID: <nanoid>.

Postman collection

A ready-to-import Postman collection with 27 example requests (discovery, standard/advanced/large calls, multi-chain, batching, idempotency, error cases) is available in our public workspace:

Venice Crypto RPC — Postman Collection

Set the apiKey collection variable to your Venice API key and start sending requests immediately.

Authorizations

BearerAuthsiwx

Authorization · string · header · required

Bearer authentication header of the form Bearer <token>, where <token> is your auth token.

Headers

Idempotency-Key · string

Optional idempotency key for safe retries. Pattern: [A-Za-z0-9_-]{1,255}. Retrying within 24 hours with the same key + same body replays the cached response with Idempotent-Replayed: true. Same key + different body returns 400.

Pattern: ^[A-Za-z0-9_-]{1,255}$

Example:

"a1b2c3d4-e5f6-7890-abcd-ef1234567890"

Path Parameters

network · string · required

Venice-side network slug. Call GET /api/v1/crypto/rpc/networks for the current list.

Example:

"ethereum-mainnet"

Body

application/json

object

object[]

method · string · required

JSON-RPC method name. See the "Supported methods" section of the endpoint description for the classification into 1×/2×/4× pricing tiers.

Example:

"eth_chainId"

jsonrpc · enum<string>

Available options: 2.0

Example:

"2.0"

params · any[]

Method parameters. Shape depends on the method; see the upstream chain documentation.

Example:

[]

id · integer string

Caller-supplied request ID echoed back in the response. Required for batch request correlation.

Example:

1

Response

200

application/json

JSON-RPC response forwarded from the upstream node. Content-Type is forced to application/json regardless of upstream headers.

object

object[]

jsonrpc · string

Example:

"2.0"

id · integer string

result · any

Method-dependent result. Present on success.

error · object

JSON-RPC error object. Present on per-request failure (HTTP status is still 200 in that case).

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