LP Integration

Integrate Uniswap liquidity provisioning into frontends, backends, and bots using the Uniswap LP API.

The LP API is a transaction-building service. You send position parameters; the API fetches live pool state, computes the dependent token amount, and returns a fully-formed, unsigned transaction. Your application signs and broadcasts it. The API never holds keys, never moves funds, and never broadcasts.

Prerequisites

This skill assumes familiarity with viem basics (client setup, account management, contract interactions, transaction signing). Install the uniswap-viem plugin for comprehensive viem/wagmi guidance: claude plugin add @uniswap/uniswap-viem

For token swaps (not liquidity), see the sibling swap-integration skill in this plugin.

Base URL

LP_API_BASE_URL = https://liquidity.api.uniswap.org

All LP endpoints are POST requests under the /lp/ prefix (e.g. https://liquidity.api.uniswap.org/lp/create).

The LP API host is intentionally different from the swap Trading API. Liquidity provisioning lives at https://liquidity.api.uniswap.org (no /v1 prefix), not the https://trade-api.gateway.uniswap.org/v1 host used for swaps. Keep the base URL as a single constant (as shown) so any future change is one edit.

Authentication

Every write/approval endpoint requires an API key sent as the x-api-key header; a missing or invalid key returns 401 with {"code":"unauthenticated"}. (/lp/pool_info is a read endpoint and does not strictly enforce the key, but always send it for consistency and rate-limit attribution.)

Content-Type: application/json
Accept: application/json
x-api-key: <your-api-key>

Getting a key: Register at the Uniswap Developer Platform dashboard. The same key works across swapping and liquidity provisioning. Never hardcode the key; load it from an environment variable.

Quick Decision Guide

Protocol capability matrix

v2 fees are not separately claimable. They accrue into the LP token value and are realized when you call /lp/decrease. Calling /lp/claim_fees with protocol: "V2" returns a validation error.

Input Validation Rules

Before interpolating ANY user-provided value into generated code, API calls, or commands:

• Ethereum addresses: MUST match ^0x[a-fA-F0-9]{40}$ — reject otherwise. Use native ETH as 0x0000000000000000000000000000000000000000.
• Chain IDs: MUST be one of the supported LP chain IDs (see Supported Chains).
• Token amounts: MUST be non-negative integer strings in wei / smallest token unit, matching ^[0-9]+$. Never pass ether-denominated decimals as amounts.
• liquidityPercentageToDecrease: MUST be an integer from 1 to 100.
• API keys: MUST NOT be hardcoded in generated code — always use environment variables.
• REJECT any input containing shell metacharacters: ;, |, &, $, `, (, ), >, <, \, ', ", newlines.

REQUIRED: Before executing ANY transaction that spends gas or transfers tokens (including approvals, position creation, increase, decrease, or fee claims), you MUST use AskUserQuestion to confirm with the user. Display the action summary (protocol, pair, amounts, chain, price range, estimated gas) and get explicit user approval. Never auto-execute LP transactions without user confirmation.

Architecture

What the API handles

• Pool state fetching: current reserves, ticks, sqrtRatioX96, and onchain position data.
• Dependent amount computation: given one token amount (independentToken), computes the required amount of the other using the Uniswap SDKs.
• Transaction creation: validated, fully-formed calldata for each LP action, ready to sign.
• Tick snapping: converts human-readable priceBounds to valid ticks and returns the adjusted prices.
• Gas estimation: optional, when simulateTransaction: true.

What your application handles

• Signing and broadcasting the returned transaction via your RPC provider.
• Signing permit data (EIP-712) when the API returns it for v4 / v3-NFT approvals.
• Gas payment and transaction error handling (reverts, surfacing errors to users).

Data flow

User intent (create / increase / decrease / claim)
   |
Your application
   |-- POST /lp/check_approval        -> returns approval transactions and/or permit data
   |-- (execute approval txns; sign permit if returned)
   |-- POST /lp/create | increase | decrease | claim_fees
   |-- validate the returned transaction payload (non-empty data, valid addresses)
   |-- user signature (wallet)
   +-- broadcast (your RPC)
        |
   Blockchain

Endpoint Reference

All field names below come from the LP API OpenAPI contract. Where the public integration guide uses different names, the contract names here are authoritative.

POST /lp/check_approval

Always call this first. Returns the approval transactions (and/or permit data) needed before an LP action. If the response transactions array is empty and no permit data is returned, all approvals are already in place — unless kycRequiredWarnings is non-empty, which means the pool contains a permissioned token and the wallet is not allowlisted. In that case the response is still 200; render the KYC call-to-action from each warning's kycUrl instead of attempting the LP action.

Request

{
  "walletAddress": "0x...",
  "protocol": "V4",
  "chainId": 1,
  "lpTokens": [
    { "tokenAddress": "0x...", "amount": "1000000000000000000" },
    { "tokenAddress": "0x...", "amount": "500000000" }
  ],
  "action": "CREATE"
}

Response

interface CheckApprovalResponse {
  requestId: string;
  transactions: ApprovalTransactionRequest[]; // sign each .transaction; empty (with kycRequiredWarnings also empty) = nothing to approve
  v4BatchPermitData?: NullablePermit; // v4: sign and pass into /lp/create or /lp/increase
  v3NftPermitData?: NullablePermit; // v3 NFT permit
  kycRequiredWarnings: KycRequiredWarning[]; // permissioned pools: non-empty when the wallet is NOT allowlisted. Always present (usually []).
}

interface ApprovalTransactionRequest {
  transaction: TransactionRequest; // the tx to sign and broadcast
  cancelApproval: boolean;
  action: 'CREATE' | 'INCREASE' | 'DECREASE' | 'MIGRATE';
  gasFee?: string;
}

interface KycRequiredWarning {
  kycUrl: string;
  tokenAddress: string;
  chainId: number;
}

The response field is transactions, not approvals. Each element WRAPS a transaction. Sign element.transaction, never the element object itself. There are no top-level token/spender fields.

POST /lp/create

Create a v3 or v4 concentrated-liquidity position. Specify a price range and one token amount; the API computes the other from live pool state.

Pool specification — provide exactly one of:

• existingPool: { token0Address, token1Address, poolReference } where poolReference is the pool address (v3) or pool ID (v4).
• newPool: { token0Address, token1Address, fee, tickSpacing, hooks?, initialPrice } where initialPrice is a sqrtRatioX96 string (hooks is v4-only).

Price range — provide exactly one of:

• priceBounds: { minPrice, maxPrice, quotedTokenAddress } — minPrice/maxPrice are decimal price strings and quotedTokenAddress is required (it must equal token0Address or token1Address). quotedTokenAddress sets which token the prices are denominated in; there is no default, and omitting it returns a 400. The API snaps to valid ticks and returns the adjusted prices.
• tickBounds: { tickLower, tickUpper } raw integers.

Request

{
  "walletAddress": "0x...",
  "chainId": 1,
  "protocol": "V3",
  "existingPool": {
    "token0Address": "0x1f9840a85d5af5bf1d1762f925bdaddc4201f984",
    "token1Address": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
    "poolReference": "0x3470447f3cecffac709d3e783a307790b0208d60"
  },
  "independentToken": {
    "tokenAddress": "0x1f9840a85d5af5bf1d1762f925bdaddc4201f984",
    "amount": "198251669183062942"
  },
  "priceBounds": {
    "minPrice": "0.00000000000324",
    "maxPrice": "0.00000000000393",
    "quotedTokenAddress": "0xdAC17F958D2ee523a2206206994597C13D831ec7"
  },
  "simulateTransaction": false
}

Response

interface CreatePositionResponse {
  requestId: string;
  token0: LPToken; // { tokenAddress, amount }
  token1: LPToken;
  adjustedMinPrice: string; // show THIS to the user, not your input minPrice
  adjustedMaxPrice: string;
  tickLower: number;
  tickUpper: number;
  create: TransactionRequest;
  gasFee?: string; // present when simulateTransaction: true
  slippage?: number; // effective slippage the API applied (e.g. native-token v4 cases)
}

Display adjustedMinPrice / adjustedMaxPrice (the tick-snapped values), not the original priceBounds you sent.

POST /lp/create_classic

Create a v2 (full-range) position. Provide one independentToken amount; the API computes the dependentToken from current pair reserves.

Request

{
  "walletAddress": "0x...",
  "poolParameters": {
    "token0Address": "0xc02fe7317d4eb8753a02c35fe019786854a92001",
    "token1Address": "0x0000000000000000000000000000000000000000",
    "chainId": 130
  },
  "independentToken": {
    "tokenAddress": "0xc02fe7317d4eb8753a02c35fe019786854a92001",
    "amount": "1000000000000000"
  },
  "simulateTransaction": false
}

Response: { requestId, independentToken, dependentToken, create: TransactionRequest, gasFee? }. Note the create_classic response names the tokens independentToken / dependentToken (not token0 / token1).

POST /lp/increase

Add liquidity to an existing v2/v3/v4 position. Provide one token amount; the API computes the other.

Request

{
  "walletAddress": "0x...",
  "chainId": 130,
  "protocol": "V4",
  "token0Address": "0x0000000000000000000000000000000000000000",
  "token1Address": "0x078D782b760474a361dDA0AF3839290b0EF57AD6",
  "nftTokenId": "1833079",
  "independentToken": {
    "tokenAddress": "0x078D782b760474a361dDA0AF3839290b0EF57AD6",
    "amount": "8223"
  },
  "simulateTransaction": false
}

Response: { requestId, token0, token1, increase: TransactionRequest, gasFee?, slippage? }.

Native ETH: use 0x0000000000000000000000000000000000000000. The API generates a multicall including refundETH to return any excess.

POST /lp/decrease

Remove a percentage of liquidity from a v2/v3/v4 position.

Request

{
  "walletAddress": "0x...",
  "chainId": 130,
  "protocol": "V4",
  "token0Address": "0x0000000000000000000000000000000000000000",
  "token1Address": "0x078D782b760474a361dDA0AF3839290b0EF57AD6",
  "liquidityPercentageToDecrease": 25,
  "nftTokenId": "1833079",
  "simulateTransaction": false
}

Response: { requestId, token0, token1, decrease: TransactionRequest, gasFee? }.

v3 fee collection on decrease: for v3, the returned decrease calldata bundles uncollected fees into the withdrawal automatically, so you do not need to call /lp/claim_fees separately. Note the response token0 / token1 amounts reflect only the pro-rata liquidity removed — the swept fees are encoded in the calldata, not added to those response amounts.

POST /lp/claim_fees

Collect accumulated trading fees from a v3 or v4 position. Not available for v2.

Request

{
  "protocol": "V4",
  "walletAddress": "0x...",
  "chainId": 130,
  "tokenId": "1833079",
  "simulateTransaction": false
}

Response: { requestId, token0, token1, claim: TransactionRequest, gasFee? }.

POST /lp/pool_info

Read live pool state (reserves, tick, sqrtRatioX96, liquidity) for one or more pools.

Request: { protocol, poolParameters?, poolReferences?, chainId?, pageSize?, currentPage? } (only protocol is strictly required; supply poolParameters { tokenAddressA, tokenAddressB, fee?, tickSpacing?, hookAddress? } or poolReferences to identify pools).

Response: { requestId, pools: PoolInformation[], pageSize, currentPage } where each PoolInformation includes poolReferenceIdentifier, poolProtocol, tokenAddressA, tokenAddressB, tickSpacing, fee, hookAddress, chainId, tokenAmountA, tokenAmountB, tokenDecimalsA, tokenDecimalsB, poolLiquidity, sqrtRatioX96, currentTick, token0Reserves, token1Reserves (note: address/amount/decimals fields use the A/B suffix, but the two reserve fields use 0/1). Optional fields (e.g. amounts, hookAddress, reserves) are omitted when not applicable to the pool.

Field-name quirks to preserve

The same concept is named differently across endpoints. Use the exact name per endpoint:

Approval and Permit Flow

Always call /lp/check_approval before any LP action, even when approvals were previously granted (allowances can be revoked or consumed).

Onchain approvals

const res = await fetch(`${LP_API_BASE_URL}/lp/check_approval`, {
  method: 'POST',
  headers: { 'x-api-key': API_KEY, 'Content-Type': 'application/json', Accept: 'application/json' },
  body: JSON.stringify({ walletAddress, protocol: 'V4', chainId: 1, lpTokens, action: 'CREATE' }),
});
if (!res.ok) throw new Error(`check_approval failed: ${res.status}`);
const { transactions, v4BatchPermitData, kycRequiredWarnings } = await res.json();

// A permissioned pool gates LPing on KYC: a non-empty kycRequiredWarnings means render the
// KYC CTA (warning.kycUrl) and stop — do NOT treat empty transactions as "approved" here.
if (kycRequiredWarnings?.length)
  throw new Error('Wallet not allowlisted for this permissioned pool');

// transactions is an array of ApprovalTransactionRequest. Empty (and no KYC warnings) => already approved.
for (const approval of transactions) {
  validateLpTransaction(approval.transaction); // see Critical Notes
  const hash = await walletClient.sendTransaction(approval.transaction);
  await publicClient.waitForTransactionReceipt({ hash });
}

v4 permit (EIP-712 sign-and-return)

For v4, check_approval returns a v4BatchPermitData (a gasless Permit2 batch approval) — often alongside onchain ERC-20 → Permit2 approval transactions, not instead of them. Execute any returned transactions first (Permit2 needs the ERC-20 allowance), then sign the permit offchain and pass it into the next call.

The permit payload is proto-encoded and is NOT directly viem-ready. Normalize two fields before signing — the un-normalized object is still what you send back to the API:

• domain.chainId arrives as the chain enum-name string (e.g. "UNICHAIN"), not a number — replace it with the numeric chain ID.
• each types entry is wrapped as { fields: [...] }; viem (and the EIP-712 spec) expect a bare array — unwrap .fields.

let signature: string | undefined;
if (v4BatchPermitData) {
  // Normalize the proto-encoded permit into viem's TypedData shape (for signing only).
  const types = Object.fromEntries(
    Object.entries(v4BatchPermitData.types).map(([k, v]) => [k, (v as any).fields])
  );
  const domain = { ...v4BatchPermitData.domain, chainId }; // numeric chainId (e.g. 130), NOT "UNICHAIN"

  signature = await walletClient.signTypedData({
    domain,
    types,
    message: v4BatchPermitData.values,
    primaryType: 'PermitBatch',
  });
}

// Send the ORIGINAL (un-normalized) permit back to the API, with the signature.
// /lp/create (uses batchPermitData) ...
const createBody = { ...createParams, batchPermitData: v4BatchPermitData, signature };
// ... or /lp/increase (uses v4BatchPermitData)
const increaseBody = { ...increaseParams, v4BatchPermitData, signature };

For full typed implementations (v3 NFT permit, EIP712Domain edge cases, migration), see Advanced Patterns Reference.

Critical Implementation Notes

1. Sign the wrapped transaction, not the wrapper

/lp/check_approval returns transactions: ApprovalTransactionRequest[]. Each element is { transaction, cancelApproval, action, gasFee? }.

// WRONG — signs the wrapper object, not a transaction
for (const a of transactions) await walletClient.sendTransaction(a);

// CORRECT
for (const a of transactions) await walletClient.sendTransaction(a.transaction);

2. Use the contract's response field names

// WRONG — these names come from the narrative guide, not the contract
const { approvals } = await checkApprovalRes.json();
const { minPrice, maxPrice } = createResponse;

// CORRECT
const { transactions } = await checkApprovalRes.json();
const { adjustedMinPrice, adjustedMaxPrice } = createResponse;

3. Never modify, always validate the data field

The create / increase / decrease / claim field holds pre-validated calldata.

function validateLpTransaction(tx: TransactionRequest): void {
  if (!tx.data || tx.data === '' || tx.data === '0x') throw new Error('Empty transaction data');
  if (!tx.to || !isAddress(tx.to)) throw new Error('Invalid recipient address');
  if (!tx.from || !isAddress(tx.from)) throw new Error('Invalid sender address');
  if (tx.maxFeePerGas && tx.gasPrice) throw new Error('Cannot set both maxFeePerGas and gasPrice');
}

Never edit the calldata — modifying it can cause reverts or loss of funds.

4. Transactions are time-sensitive

Pool price moves. If the user takes more than ~30 seconds to review, refetch the transaction before broadcasting.

const TX_EXPIRY_MS = 30_000;
const builtAt = Date.now();
// ... user reviews ...
if (Date.now() - builtAt > TX_EXPIRY_MS) lpTx = await refetchLpTransaction(params);

5. Amounts are wei strings

All amount fields are integer strings in the token's smallest unit. Convert with parseUnits(value, decimals).toString() — never send ether-denominated decimals.

6. Strip undefined optional fields

Send permit fields as a matched pair (batchPermitData + signature) or omit both. Do not send signature: undefined alongside a present permit, or vice versa.

Worked Example: Create a v3 Position (viem)

import { createWalletClient, createPublicClient, http, isAddress, parseUnits } from 'viem';
import { mainnet } from 'viem/chains';
import { privateKeyToAccount } from 'viem/accounts';

const LP_API_BASE_URL = 'https://liquidity.api.uniswap.org';
const API_KEY = process.env.UNISWAP_API_KEY!; // never hardcode

const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
const walletClient = createWalletClient({
  account,
  chain: mainnet,
  transport: http(process.env.RPC_URL),
});
const publicClient = createPublicClient({ chain: mainnet, transport: http(process.env.RPC_URL) });

const headers = {
  'x-api-key': API_KEY,
  'Content-Type': 'application/json',
  Accept: 'application/json',
};

async function lpFetch(path: string, body: object) {
  const res = await fetch(`${LP_API_BASE_URL}${path}`, {
    method: 'POST',
    headers,
    body: JSON.stringify(body),
  });
  if (!res.ok) throw new Error(`${path} failed: ${res.status} ${await res.text()}`);
  return res.json();
}

// Same checks as the canonical validateLpTransaction in "Critical Implementation Notes" above.
function validateLpTransaction(tx: any) {
  if (!tx || !tx.data || tx.data === '' || tx.data === '0x')
    throw new Error('Empty transaction data');
  if (!tx.to || !isAddress(tx.to)) throw new Error('Invalid recipient address');
  if (!tx.from || !isAddress(tx.from)) throw new Error('Invalid sender address');
  if (tx.maxFeePerGas && tx.gasPrice) throw new Error('Cannot set both maxFeePerGas and gasPrice');
}

async function createV3Position() {
  const protocol = 'V3';
  const chainId = 1;
  const token0Address = '0x1f9840a85d5af5bf1d1762f925bdaddc4201f984'; // UNI
  const token1Address = '0xdAC17F958D2ee523a2206206994597C13D831ec7'; // USDT
  const independentToken = { tokenAddress: token0Address, amount: parseUnits('10', 18).toString() };

  // 1. Approvals
  const { transactions } = await lpFetch('/lp/check_approval', {
    walletAddress: account.address,
    protocol,
    chainId,
    lpTokens: [independentToken],
    action: 'CREATE',
  });
  for (const a of transactions) {
    validateLpTransaction(a.transaction);
    const hash = await walletClient.sendTransaction(a.transaction);
    await publicClient.waitForTransactionReceipt({ hash });
  }

  // 2. Build the create transaction
  const created = await lpFetch('/lp/create', {
    walletAddress: account.address,
    chainId,
    protocol,
    independentToken,
    existingPool: {
      token0Address,
      token1Address,
      poolReference: '0x3470447f3cecffac709d3e783a307790b0208d60',
    },
    priceBounds: {
      minPrice: '0.00000000000324',
      maxPrice: '0.00000000000393',
      quotedTokenAddress: token1Address,
    },
    simulateTransaction: true,
  });

  // 3. CONFIRM WITH USER before broadcasting (use AskUserQuestion in the skill flow):
  //    pair, amounts (created.token0 / created.token1), adjusted range
  //    (created.adjustedMinPrice / created.adjustedMaxPrice), created.gasFee
  validateLpTransaction(created.create);
  const hash = await walletClient.sendTransaction(created.create);
  return publicClient.waitForTransactionReceipt({ hash });
}

Companion SDKs

The API returns ready-to-sign transactions, so a protocol SDK is not required. For client-side pool/position math, tick conversions, and validation, developers commonly pair the LP API with:

• @uniswap/sdk-core — chains, Token, CurrencyAmount, Percent, Price (foundational).
• @uniswap/v3-sdk — v3 tick math (TickMath, nearestUsableTick), Pool, Position.
• @uniswap/v4-sdk — v4 pool keys, hooks-aware Position modeling.
• @uniswap/v2-sdk — v2 pair/liquidity math.
• viem (or ethers) — sign and broadcast the returned { to, data, value }, and sign EIP-712 permit data.

Error Handling

Error body (Connect protocol): { code: string, message: string, details?: Array<{ type: string; value: string }> } — e.g. {"code":"invalid_argument","message":"RequestValidationError: ...","details":[...]}. code is a Connect error-code string (invalid_argument, unauthenticated, failed_precondition, internal, …), not an HTTP number, and there is no top-level error field. Read body.code / body.message, not body.error.

Common errors

• v2 fee claim attempt: calling /lp/claim_fees with protocol: "V2". Use /lp/decrease to realize v2 fees.
• Pool not found: verify token addresses, the poolReference, and the chain; or use newPool to initialize.
• Insufficient liquidity: the computed dependent amount exceeds balances; reduce independentToken.amount or widen the range.
• Validation error: ensure all required fields for the chosen protocol, checksummed addresses, wei-denominated amounts, and liquidityPercentageToDecrease in 1-100.

For retry/backoff, request caching, monitoring, and the full pre-broadcast checklist, see Advanced Patterns Reference.

Supported Chains

The LP API supports a fixed set of chain IDs. Validate chainId against this set before sending:

1, 10, 56, 130, 137, 143, 196, 324, 480, 1868, 4217, 4326, 4663, 5042,
8453, 10143, 42161, 42220, 43114, 59144, 81457, 7777777, 1301, 84532, 11155111

(Mainnet 1, Optimism 10, BNB 56, Unichain 130, Polygon 137, Base 8453, Arbitrum 42161, Avalanche 43114, Linea 59144, Blast 81457, Zora 7777777, Sepolia 11155111, and others.) Confirm the live set against /lp/pool_info availability or the supported chains docs.

Additional Resources

• LP API: Getting Started — official conceptual overview
• LP API: Integration Guide — official guide
• Uniswap Developer Platform dashboard — get an API key
• swap-integration — sibling skill for token swaps via the Trading API
• Advanced Patterns Reference — permit deep-dive, migration, NFT-position quirks, reliability