Primev Documentation

Complete technical documentation for mev-commit, Fast Protocol, FAST RPC, and Fastx402 — Ethereum infrastructure for preconfirmations, instant swaps, and agentic payments.

Primev builds core infrastructure for Ethereum's mev supply chain. The mev-commit protocol enables peer-to-peer preconfirmation commitments between bidders and block builders, providing sub-second transaction guarantees on Ethereum mainnet.

Products

• FAST RPC: Drop-in Ethereum JSON-RPC replacement at https://fastrpc.mev-commit.xyz. Transactions sent through FAST RPC receive binding preconfirmation commitments from block builders. Supports all standard eth_ methods plus custom mevcommit_ methods.
• Fast Protocol: Order flow auction (OFA) on top of mev-commit. Users receive at least 90% of mev their transactions generate. Redistributed as Fast Miles (tokenizable points).
• Fast Swaps: Token swap interface on Ethereum mainnet. Gasless ERC-20 swaps via EIP-712 signed intents through Permit2. Supports 2,400+ tokens. Settlement via FastSettlement V3 contract on L1.
• Fastx402: x402 payment facilitator for AI agents. USDC payments via EIP-3009 transferWithAuthorization. Sub-second settlement through FAST RPC. Zero fees. Endpoint: https://facilitator.primev.xyz.

FAST RPC API

Endpoint: https://fastrpc.mev-commit.xyz

Standard Ethereum JSON-RPC methods are supported. Key overridden methods:

• eth_sendRawTransaction — Sources preconfirmations on mev-commit chain. Transaction is enqueued privately (not sent to public mempool). Returns transaction hash.
• eth_getTransactionReceipt — Returns receipt early if enough preconfirmations obtained for mev-commit opted-in slots. Block hash set to tx hash for preconfirmed transactions.
• eth_getTransactionCount — Returns mempool count + queued transactions in private pool.
• eth_maxPriorityFeePerGas — Always returns 0 (priority fee should be 0 for FAST RPC users).
• eth_getBlockByHash — For preconfirmed tx hashes, returns a fictitious block containing only that transaction.

Additional FAST RPC methods:

• mevcommit_getTransactionCommitments — Takes tx hash, returns array of commitments received on mev-commit network (provider addresses, signatures, decay timestamps).
• mevcommit_getBalance — Takes account address, returns available deposit balance for that address.
• mevcommit_optInBlock — Returns time in seconds until the next block with a mev-commit opted-in validator.
• mevcommit_cancelTransaction — Takes tx hash, cancels commitment attempts. No cost.
• mevcommit_estimateDeposit — Returns estimated deposit cost and EOA wallet address for funding.
• mevcommit_estimateBridge — Returns estimated bridging cost and destination address for instant L1-to-mev-commit-chain bridging.

Fastx402 API

Endpoint: https://facilitator.primev.xyz

• GET /supported — Returns supported payment kinds, extensions, and signer addresses. Response: {"kinds":[{"x402Version":2,"scheme":"exact","network":"eip155:1"}],"extensions":["bazaar"],"signers":{"eip155:*":["0x488d87a9A88a6A878B3E7cf0bEece8984af9518D"]}}
• POST /settle — Verify and settle a USDC payment on-chain via FAST RPC. Body: {"paymentPayload":{"x402Version":2,"scheme":"exact","network":"eip155:1","payload":{"signature":"0x...","authorization":{"from":"0x...","to":"0x...","value":"1000000","validAfter":"0","validBefore":"...","nonce":"0x..."}}},"paymentRequirements":{"scheme":"exact","network":"eip155:1","amount":"1000000","asset":"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","payTo":"0x...","maxTimeoutSeconds":60}}
• POST /verify — Validate a payment signature without settling (dry run). Same body as /settle.
• GET /health — Health check.

USDC contract: 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 (Ethereum mainnet, 6 decimals). Relay wallet: 0x488d87a9A88a6A878B3E7cf0bEece8984af9518D (submits transferWithAuthorization on-chain). ERC-8004 Agent ID: 23175.

Fast Swaps Contracts

• FastSettlement V3 Proxy: 0x084C0EC7f5C0585195c1c713ED9f06272F48cB45 (Ethereum L1)
• Permit2: 0x000000000022D473030F116dDEE9F6B43aC78BA3 (Uniswap canonical)

ERC-20 swap flow: User signs EIP-712 PermitWitnessTransferFrom with Intent witness (user, inputToken, outputToken, inputAmt, userAmtOut, recipient, deadline, nonce). FAST RPC calls executeWithPermit on FastSettlement. ETH swap flow: User calls executeWithETH directly.

EIP-712 signing domain: {"name":"Permit2","chainId":1,"verifyingContract":"0x000000000022D473030F116dDEE9F6B43aC78BA3"}

mev-commit Protocol

Concepts

• Preconfirmation: A binding commitment from a block builder to include a transaction. Providers stake ETH and are slashed if they break commitments.
• Bidders: Submit bids for transaction inclusion with a specified bid amount and block number.
• Providers: Block builders who stake ETH and issue commitments on bids. Rewarded for honoring commitments, slashed for breaking them.
• Oracle: Resolves commitments by checking on-chain inclusion after blocks are built.
• mev-commit chain: Dedicated PoA chain (Chain ID: 57173) for bid/commitment settlement. RPC: https://chainrpc.mev-commit.xyz.

Network Details

• mev-commit chain RPC: https://chainrpc.mev-commit.xyz (Chain ID: 57173)
• mev-commit chain WebSocket: wss://chainrpc-wss.mev-commit.xyz
• Bootnode: https://bootnode.mev-commit.xyz
• Block explorer: https://mev-commit.xyz
• Testnet chain RPC: https://chainrpc.testnet.mev-commit.xyz (Chain ID: 17864)

Validator Opt-In

Validators can opt in via three methods:

1. EigenLayer restaking — Native restaking through MevCommitAVS contract
2. Symbiotic restaking — ERC20 vault staking through MevCommitMiddleware contract
3. Vanilla staking — Direct ETH staking through VanillaRegistry contract

Opted-in validators earn ~20x higher mev capture on FAST RPC flows vs non-opted-in.

AI Agent Integration

Install the Claude Code plugin: claude plugin add primev/claude-plugin

This provides:

• 3 skills: mev-commit (preconfirmed transactions), fast-protocol (gasless swaps), x402 (USDC payments)
• 2 MCP servers: primev-fastrpc (11 tools) + primev-docs (docs search)
• 12 MCP tools: eth_blockNumber, eth_getBalance, eth_gasPrice, eth_getTransactionReceipt, eth_sendRawTransaction, eth_call, eth_chainId, x402_supported, x402_verify, mevcommit_getTransactionCommitments, mevcommit_optInBlock, search_docs

No API keys required. All endpoints are public.

Source Code

• mev-commit: Core protocol, oracle, bridge, contracts
• mev-commit-docs: This documentation
• claude-plugin: Claude Code plugin with skills and MCP server
• mainnet-x402-facilitator: Fastx402 facilitator source
• fastprotocolapp: Fast Swaps web app

Documentation Sections

• Welcome: Overview of Primev and mev-commit
• Quickstart: Getting started guide
• FAST RPC Guide: How to use FAST RPC
• Fast Swaps Guide: How to perform swaps
• FAST RPC API: Full API reference for FAST RPC methods
• Fastx402: x402 facilitator documentation
• Contracts: Contract architecture and addresses
• Networks - Mainnet: Mainnet service links and contract addresses
• Networks - Testnet: Testnet details
• Fast Protocol Economics: mev distribution model and fee parameters
• Fast Swaps Architecture: Smart contracts, EIP-712 signing, execution paths
• What is mev-commit: Protocol overview
• Actors: Bidders, providers, validators
• Commitments: How commitments work
• Bid Structure: Bid format and parameters
• Rewards and Slashing: Incentive mechanisms
• Validator Guide: How to opt in as a validator
• Provider Guide: How to register as a provider
• Bidder Best Practices: Bidding tips
• Knowledge Base: FAQs on Fast Protocol, preconfirmations, bidding, and troubleshooting

Optional

• AI Integration Page: Skills, MCP tools, and quickstart guides
• primev.xyz llms.txt: High-level product overview for LLMs
• Research Publications: Academic papers on mev and preconfirmations
• mev-commit Xplorer: Live network explorer
• Fast Swaps App: Swap interface