Transaction proofs and proof modes

This page describes the Devnet-specific transaction proof flow introduced in Starknet v0.14.2 and the --proof-mode configuration.

Not about storage proofs

starknet_getStorageProof (Merkle-Patricia storage proofs) is not supported in Devnet. This page covers starknet_proveTransaction, a separate Devnet extension for proving/validating INVOKE v3 transaction payloads.

Proof modes

Proof behavior is controlled by --proof-mode (or env var PROOF_MODE).

Mode summary

Mode	CLI value	What starknet_proveTransaction does	How starknet_addInvokeTransaction treats proof and proof_facts
Full	full	Not implemented yet	Rejects with unsupported action
Devnet	devnet (default)	Returns a deterministic mock proof + proof facts	If both fields are present, verifies them; if one is missing or verification fails, rejects; if both are absent, accepts
None	none	Disabled / unsupported	Ignores incoming proof for invoke txs

Why this exists

devnet mode is a practical mode for local testing:

• You can request a proof for a specific INVOKE v3 payload.
• You can later attach that proof to a transaction and exercise proof-aware flows.
• Verification is deterministic and lightweight, intended for development workflows rather than real on-chain proving.

Configuration

CLI

starknet-devnet --proof-mode devnet

starknet-devnet --proof-mode none

starknet-devnet --proof-mode full

Environment variable

PROOF_MODE=devnet starknet-devnet

Docker

docker run --rm -p 5050:5050 \
  -e PROOF_MODE=devnet \
  shardlabs/starknet-devnet-rs

RPC: starknet_proveTransaction

Request shape

starknet_proveTransaction accepts:

• block_id
• transaction (a broadcasted INVOKE v3 transaction payload)

Example:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "starknet_proveTransaction",
  "params": {
    "block_id": "latest",
    "transaction": {
      "type": "INVOKE",
      "version": "0x3",
      "sender_address": "0x1234",
      "calldata": ["0x1", "0x2"],
      "signature": [],
      "nonce": "0x0",
      "resource_bounds": {
        "l1_gas": { "max_amount": "0x0", "max_price_per_unit": "0x0" },
        "l1_data_gas": { "max_amount": "0x0", "max_price_per_unit": "0x0" },
        "l2_gas": { "max_amount": "0x0", "max_price_per_unit": "0x0" }
      },
      "tip": "0x0",
      "paymaster_data": [],
      "account_deployment_data": [],
      "nonce_data_availability_mode": "L1",
      "fee_data_availability_mode": "L1"
    }
  }
}

Response shape

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "proof": "<base64-encoded-proof>",
    "proof_facts": [
      "0x...",
      "0x...",
      "0x...",
      "0x...",
      "0x...",
      "0x...",
      "0x...",
      "0x...",
      "0x..."
    ],
    "l2_to_l1_messages": [
      {
        "order": 0,
        "from_address": "0x...",
        "to_address": "0x...",
        "payload": ["0x...", "0x..."]
      }
    ]
  }
}

proof_facts length is expected to be 9 in devnet mode (includes a messages_hash element derived from L2→L1 messages).

l2_to_l1_messages contains L2→L1 messages extracted by simulating the transaction. If the simulation fails (e.g. execution reverts), starknet_proveTransaction returns an error instead of a proof.

Mode-specific behavior details

devnet mode (default)

• starknet_proveTransaction is enabled.
• Invoke handling rules:
  • both proof + proof_facts present and valid → accepted
  • both present but invalid → rejected
  • only one present → rejected
  • both absent → accepted

none mode

• Proof field on invoke transactions is ignored; proof_facts are checked.

full mode

• Full proving/verification is not implemented yet.
• Endpoints and transactions requiring full verification return unsupported-action errors.