diff --git a/lib/wallet/rpc.js b/lib/wallet/rpc.js
index a73830b2..e916cc5a 100644
--- a/lib/wallet/rpc.js
+++ b/lib/wallet/rpc.js
@@ -2762,7 +2762,7 @@ class RPC extends RPCBase {
             'NONE action requires 2 arguments: address, value'
           );
           const {addr, value} = this._validateSendToAddress(action);
-          actions.push([type, addr, value]);
+          actions.push({ type: type, args: [addr, value] });
           break;
         }
         case 'OPEN': {
@@ -2771,7 +2771,7 @@ class RPC extends RPCBase {
             'OPEN action requires 1 argument: name'
           );
           const {name} = this._validateOpen(action);
-          actions.push([type, name]);
+          actions.push({ type: type, args: [name] });
           break;
         }
         case 'BID': {
@@ -2780,7 +2780,7 @@ class RPC extends RPCBase {
             'BID action requires 3 arguments: name, bid, value'
           );
           const {name, bid, value} = this._validateBid(action);
-          actions.push([type, name, bid, value]);
+          actions.push({ type: type, args: [name, bid, value] });
           break;
         }
         case 'REVEAL': {
@@ -2790,9 +2790,9 @@ class RPC extends RPCBase {
           );
           const {name} = this._validateReveal(action);
           if (name)
-            actions.push([type, name]);
+            actions.push({ type: type, args: [name] });
           else
-            actions.push([type]);
+            actions.push({ type: type });
           break;
         }
         case 'REDEEM': {
@@ -2802,9 +2802,9 @@ class RPC extends RPCBase {
           );
           const {name} = this._validateRedeem(action);
           if (name)
-            actions.push([type, name]);
+            actions.push({ type: type, args: [name] });
           else
-            actions.push([type]);
+            actions.push({ type: type });
           break;
         }
         case 'UPDATE': {
@@ -2813,7 +2813,7 @@ class RPC extends RPCBase {
             'UPDATE action requires 2 arguments: name, data'
           );
           const {name, resource} = this._validateUpdate(action);
-          actions.push([type, name, resource]);
+          actions.push({ type: type, args: [name, resource] });
           break;
         }
         case 'RENEW': {
@@ -2823,9 +2823,9 @@ class RPC extends RPCBase {
           );
           if (action.length === 1) {
             const {name} = this._validateRenewal(action);
-            actions.push([type, name]);
+            actions.push({ type: type, args: [name] });
           } else {
-            actions.push([type]);
+            actions.push({ type: type });
           }
           break;
         }
@@ -2835,7 +2835,7 @@ class RPC extends RPCBase {
             'TRANSFER action requires 2 arguments: name, address'
           );
           const {name, address} = this._validateTransfer(action);
-          actions.push([type, name, address]);
+          actions.push({ type: type, args: [name, address] });
           break;
         }
         case 'FINALIZE': {
@@ -2845,9 +2845,9 @@ class RPC extends RPCBase {
           );
           if (action.length === 1) {
             const {name} = this._validateFinalize(action);
-            actions.push([type, name]);
+            actions.push({ type: type, args: [name] });
           } else {
-            actions.push([type]);
+            actions.push({ type: type });
           }
           break;
         }
@@ -2857,7 +2857,7 @@ class RPC extends RPCBase {
             'CANCEL action requires 1 argument: name'
           );
           const {name} = this._validateCancel(action);
-          actions.push([type, name]);
+          actions.push({ type: type, args: [name] });
           break;
         }
         case 'REVOKE': {
@@ -2866,7 +2866,7 @@ class RPC extends RPCBase {
             'REVOKE action requires 1 argument: name'
           );
           const {name} = this._validateRevoke(action);
-          actions.push([type, name]);
+          actions.push({ type: type, args: [name] });
           break;
         }
         default:
diff --git a/lib/wallet/wallet.js b/lib/wallet/wallet.js
index f7674ec7..f1a521df 100644
--- a/lib/wallet/wallet.js
+++ b/lib/wallet/wallet.js
@@ -3861,9 +3861,15 @@ class Wallet extends EventEmitter {
     }
   }
 
+  /**
+   * @typedef {Object} BatchAction
+   * @property {String} type - Action type
+   * @property {Array} [args] - Arguments for the action
+   */
+
   /**
    * Make a batch transaction with multiple actions.
-   * @param {Array} actions
+   * @param {BatchAction[]} actions
    * @param {Object} options
    * @returns {Promise<MTX>}
    */
@@ -3885,15 +3891,13 @@ class Wallet extends EventEmitter {
     // covenant like NONE, OPEN, or BID could shift the
     // output array out of sync with their corresponding inputs.
     actions.sort((a, b) => {
-      assert(Array.isArray(a));
-      assert(Array.isArray(b));
-      assert(a.length);
-      assert(b.length);
+      assert(a.type);
+      assert(b.type);
 
-      if (a[0] === b[0])
+      if (a.type === b.type)
         return 0;
 
-      switch (b[0]) {
+      switch (b.type) {
         case 'REVEAL':
         case 'REDEEM':
         case 'UPDATE':
@@ -3916,106 +3920,110 @@ class Wallet extends EventEmitter {
     // "actions" are arrays that start with a covenant type (or meta-type)
     // followed by the arguments expected by the corresponding "make" function.
     for (const action of actions) {
-      const type = action.shift();
-      assert(typeof type === 'string');
+      assert(action);
+      assert(typeof action.type === 'string');
 
-      switch (type) {
+      const args =  action.args || [];
+
+      assert(Array.isArray(args), 'Action args must be an array.');
+
+      switch (action.type) {
         case 'NONE': {
-          assert(action.length === 2);
+          assert(args.length === 2);
           this.makeTX([{
-            address: action[0],
-            value: action[1]
+            address: args[0],
+            value: args[1]
           }], mtx);
 
           break;
         }
         case 'OPEN': {
-          assert(action.length === 1, 'Bad arguments for OPEN.');
-          const name = action[0];
+          assert(args.length === 1, 'Bad arguments for OPEN.');
+          const name = args[0];
           await this.makeOpen(name, acct, mtx);
           break;
         }
         case 'BID': {
-          assert(action.length === 3, 'Bad arguments for BID.');
+          assert(args.length === 3, 'Bad arguments for BID.');
           const address = account.deriveReceive(receiveIndex++).getAddress();
-          const name = action[0];
-          const value = action[1];
-          const lockup = action[2];
+          const name = args[0];
+          const value = args[1];
+          const lockup = args[2];
           await this.makeBid(name, value, lockup, acct, mtx, address);
           break;
         }
         case 'REVEAL': {
-          if (action.length === 1) {
-            const name = action[0];
+          if (args.length === 1) {
+            const name = args[0];
             await this.makeReveal(name, acct, mtx);
             break;
           }
 
-          assert(action.length === 0, 'Bad arguments for REVEAL.');
+          assert(args.length === 0, 'Bad arguments for REVEAL.');
           await this.makeRevealAll(mtx, witnessSize);
           break;
         }
         case 'REDEEM': {
-          if (action.length === 1) {
-            const name = action[0];
+          if (args.length === 1) {
+            const name = args[0];
             await this.makeRedeem(name, acct, mtx);
             break;
           }
 
-          assert(action.length === 0, 'Bad arguments for REDEEM.');
+          assert(args.length === 0, 'Bad arguments for REDEEM.');
           await this.makeRedeemAll(mtx, witnessSize);
           break;
         }
         case 'UPDATE': {
-          assert(action.length === 2, 'Bad arguments for UPDATE.');
-          const name = action[0];
-          const resource = action[1];
+          assert(args.length === 2, 'Bad arguments for UPDATE.');
+          const name = args[0];
+          const resource = args[1];
           await this.makeUpdate(name, resource, acct, mtx);
           break;
         }
         case 'RENEW': {
-          if (action.length === 1) {
-            const name = action[0];
+          if (args.length === 1) {
+            const name = args[0];
             await this.makeRenewal(name, acct, mtx);
             break;
           }
 
-          assert(action.length === 0, 'Bad arguments for RENEW.');
+          assert(args.length === 0, 'Bad arguments for RENEW.');
           await this.makeRenewalAll(mtx, witnessSize);
           break;
         }
         case 'TRANSFER': {
-          assert(action.length === 2, 'Bad arguments for TRANSFER.');
-          const name = action[0];
-          const address = action[1];
+          assert(args.length === 2, 'Bad arguments for TRANSFER.');
+          const name = args[0];
+          const address = args[1];
           await this.makeTransfer(name, address, acct, mtx);
           break;
         }
         case 'FINALIZE': {
-          if (action.length === 1) {
-            const name = action[0];
+          if (args.length === 1) {
+            const name = args[0];
             await this.makeFinalize(name, acct, mtx);
             break;
           }
 
-          assert(action.length === 0, 'Bad arguments for FINALIZE.');
+          assert(args.length === 0, 'Bad arguments for FINALIZE.');
           await this.makeFinalizeAll(mtx, witnessSize);
           break;
         }
         case 'CANCEL': {
-          assert(action.length === 1, 'Bad arguments for CANCEL.');
-          const name = action[0];
+          assert(args.length === 1, 'Bad arguments for CANCEL.');
+          const name = args[0];
           await this.makeCancel(name, acct, mtx);
           break;
         }
         case 'REVOKE': {
-          assert(action.length === 1, 'Bad arguments for REVOKE.');
-          const name = action[0];
+          assert(args.length === 1, 'Bad arguments for REVOKE.');
+          const name = args[0];
           await this.makeRevoke(name, acct, mtx);
           break;
         }
         default:
-          throw new Error(`Unknown action type: ${type}`);
+          throw new Error(`Unknown action type: ${action.type}`);
       }
 
       if (rules.countOpens(mtx) > consensus.MAX_BLOCK_OPENS)
diff --git a/test/wallet-auction-test.js b/test/wallet-auction-test.js
index e5281fe4..b7a343d2 100644
--- a/test/wallet-auction-test.js
+++ b/test/wallet-auction-test.js
@@ -698,9 +698,9 @@ describe('Wallet Auction', function() {
     it('should create multiple OPENs with options', async () => {
       const mtx = await wallet.createBatch(
         [
-          ['OPEN', name1],
-          ['OPEN', name2],
-          ['OPEN', name3]
+          { type: 'OPEN', args: [name1] },
+          { type: 'OPEN', args: [name2] },
+          { type: 'OPEN', args: [name3] }
         ],
         {
           hardFee
@@ -730,9 +730,9 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['OPEN', 'google'],
-            ['OPEN', name2],
-            ['OPEN', name3]
+            { type: 'OPEN', args: ['google'] },
+            { type: 'OPEN', args: [name2] },
+            { type: 'OPEN', args: [name3] }
           ]
         ),
         {message: 'Name is reserved: google.'}
@@ -743,9 +743,9 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['OPEN', name1],
-            ['OPEN', name1],
-            ['OPEN', name3]
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name3] }
           ]
         ),
          {message: 'Duplicate name with exclusive action.'}
@@ -756,9 +756,9 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['OPEN', name1],
-            ['OPEN', name1],
-            ['OPEN', name3]
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name3] }
           ]
         ),
          {message: 'Duplicate name with exclusive action.'}
@@ -769,9 +769,9 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['BID', name1, 1, 1],
-            ['OPEN', name2],
-            ['OPEN', name3]
+            { type: 'BID', args: [name1, 1, 1] },
+            { type: 'OPEN', args: [name2] },
+            { type: 'OPEN', args: [name3] }
           ]
         ),
         {message: `Name has not reached the bidding phase yet: ${name1}.`}
@@ -782,9 +782,9 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['BID', name1, 21000000],
-            ['OPEN', name2],
-            ['OPEN', name3]
+            { type: 'BID', args: [name1, 21000000] },
+            { type: 'OPEN', args: [name2] },
+            { type: 'OPEN', args: [name3] }
           ]
         ),
         {message: 'Bad arguments for BID.'}
@@ -795,7 +795,7 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['REVEAL']
+            { type: 'REVEAL' }
           ]
         ),
         {message: 'Nothing to do.'}
@@ -806,7 +806,7 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['REDEEM']
+            { type: 'REDEEM' }
           ]
         ),
         {message: 'Nothing to do.'}
@@ -818,10 +818,10 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['OPEN', name1],
-            ['OPEN', name1],
-            ['OPEN', name3],
-            ['NONE', addr, 1]
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name3] },
+            { type: 'NONE', args: [addr, 1] }
           ]
         ),
          {message: 'Output is dust.'}
@@ -832,10 +832,10 @@ describe('Wallet Auction', function() {
       await assert.rejects(
         wallet.sendBatch(
           [
-            ['OPEN', name1],
-            ['OPEN', name1],
-            ['OPEN', name3],
-            ['open', name4]
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name3] },
+            { type: 'open', args: [name4] }
           ]
         ),
          {message: 'Unknown action type: open'}
@@ -847,10 +847,10 @@ describe('Wallet Auction', function() {
       it('3 OPENs and 1 NONE', async () => {
         const tx = await wallet.sendBatch(
           [
-            ['OPEN', name1],
-            ['OPEN', name2],
-            ['OPEN', name3],
-            ['NONE', addr, 10000]
+            { type: 'OPEN', args: [name1] },
+            { type: 'OPEN', args: [name2] },
+            { type: 'OPEN', args: [name3] },
+            { type: 'NONE', args: [addr, 10000] }
           ]
         );
 
@@ -861,10 +861,10 @@ describe('Wallet Auction', function() {
       it('4 BIDs', async () => {
         const tx = await wallet.sendBatch(
           [
-            ['BID', name1, 10000, 20000],
-            ['BID', name1, 10001, 20000], // self-snipe!
-            ['BID', name2, 30000, 40000],
-            ['BID', name3, 50000, 60000]
+            { type: 'BID', args: [name1, 10000, 20000] },
+            { type: 'BID', args: [name1, 10001, 20000] }, // self-snipe!
+            { type: 'BID', args: [name2, 30000, 40000] },
+            { type: 'BID', args: [name3, 50000, 60000] }
           ]
         );
 
@@ -876,7 +876,7 @@ describe('Wallet Auction', function() {
         // Don't send this one
         const revealAll = await wallet.createBatch(
           [
-            ['REVEAL']
+            { type: 'REVEAL' }
           ]
         );
 
@@ -892,8 +892,8 @@ describe('Wallet Auction', function() {
       it('2 REVEALs then 1 REVEAL', async () => {
         const tx = await wallet.sendBatch(
           [
-            ['REVEAL', name1],
-            ['REVEAL', name2]
+            { type: 'REVEAL', args: [name1] },
+            { type: 'REVEAL', args: [name2] }
           ]
         );
 
@@ -903,7 +903,7 @@ describe('Wallet Auction', function() {
         // because names are being revealed individually.
         await wallet.sendBatch(
           [
-            ['REVEAL', name3]
+            { type: 'REVEAL', args: [name3] }
           ]
         );
         await mineBlocks(revealPeriod);
@@ -913,7 +913,7 @@ describe('Wallet Auction', function() {
         // Don't send this one
         const redeemAll = await wallet.createBatch(
           [
-            ['REDEEM']
+            { type: 'REDEEM' }
           ]
         );
 
@@ -930,11 +930,11 @@ describe('Wallet Auction', function() {
         // Complete all 4 bids win and/or lose in one TX
         const batch1 = await wallet.sendBatch(
           [
-            ['OPEN', name4],
-            ['REDEEM', name1],
-            ['UPDATE', name1, res1],
-            ['UPDATE', name2, res2],
-            ['UPDATE', name3, res3]
+            { type: 'OPEN', args: [name4] },
+            { type: 'REDEEM', args: [name1] },
+            { type: 'UPDATE', args: [name1, res1] },
+            { type: 'UPDATE', args: [name2, res2] },
+            { type: 'UPDATE', args: [name3, res3] }
           ]
         );
 
@@ -955,10 +955,10 @@ describe('Wallet Auction', function() {
         });
         const tx = await wallet.sendBatch(
           [
-            ['TRANSFER', name1, nullAddr],
-            ['TRANSFER', name2, nullAddr],
-            ['TRANSFER', name3, nullAddr],
-            ['BID', name4, 70000, 80000]
+            { type: 'TRANSFER', args: [name1, nullAddr] },
+            { type: 'TRANSFER', args: [name2, nullAddr] },
+            { type: 'TRANSFER', args: [name3, nullAddr] },
+            { type: 'BID', args: [name4, 70000, 80000] }
           ]
         );
 
@@ -974,10 +974,10 @@ describe('Wallet Auction', function() {
       it('1 FINALIZE, 1 CANCEL, 1 REVOKE and 1 REVEAL', async () => {
         const tx = await wallet.sendBatch(
           [
-            ['FINALIZE', name1],
-            ['CANCEL', name2],
-            ['REVOKE', name3],
-            ['REVEAL', name4]
+            { type: 'FINALIZE', args: [name1] },
+            { type: 'CANCEL', args: [name2] },
+            { type: 'REVOKE', args: [name3] },
+            { type: 'REVEAL', args: [name4] }
           ]
         );
 
@@ -992,8 +992,8 @@ describe('Wallet Auction', function() {
       it('1 revoked name re-OPEN and 1 REGISTER', async () => {
         const batch2 = await wallet.sendBatch(
           [
-            ['OPEN', name3], // and the cycle begins again...
-            ['UPDATE', name4, res4]
+            { type: 'OPEN', args: [name3] }, // and the cycle begins again...
+            { type: 'UPDATE', args: [name4, res4] }
           ]
         );
 
@@ -1010,7 +1010,7 @@ describe('Wallet Auction', function() {
         const actions = [];
         for (let i = 0; i < 10; i++) {
           const addr = Address.fromProgram(0, Buffer.alloc(20, i + 1));
-          actions.push(['NONE', addr, 10000]);
+          actions.push({ type: 'NONE', args: [addr, 10000] });
         }
 
         const batch = await wallet.sendBatch(actions, {hardFee: 1000});
@@ -1058,8 +1058,8 @@ describe('Wallet Auction', function() {
       it('2 RENEW', async () => {
         await wallet.sendBatch(
           [
-            ['RENEW', name2],
-            ['RENEW', name4]
+            { type: 'RENEW', args: [name2] },
+            { type: 'RENEW', args: [name4] }
           ]
         );
 
@@ -1130,14 +1130,16 @@ describe('Wallet Auction', function() {
 
       it('should OPEN', async () => {
         name = rules.grindName(4, chain.height, network);
-        await wallet.sendBatch([['OPEN', name]]);
+        await wallet.sendBatch([
+          { type: 'OPEN', args: [name] }
+        ]);
         await mineBlocks(treeInterval + 1);
       });
 
       it('should not batch too many BIDs', async () => {
         const batch = [];
         for (let i = 201; i > 0; i--)
-          batch.push(['BID', name, i * 1000, i * 1000]);
+          batch.push({ type: 'BID', args: [name, i * 1000, i * 1000] });
 
         await assert.rejects(
           wallet.sendBatch(batch),
@@ -1148,19 +1150,19 @@ describe('Wallet Auction', function() {
       it('should batch BIDs', async () => {
         let batch = [];
         for (let i = 200; i > 0; i--)
-          batch.push(['BID', name, i * 1000, i * 1000]);
+          batch.push({ type: 'BID', args: [name, i * 1000, i * 1000] });
         await wallet.sendBatch(batch);
         batch = [];
         for (let i = 200; i > 0; i--)
-          batch.push(['BID', name, i * 1001, i * 1001]);
+          batch.push({ type: 'BID', args: [name, i * 1001, i * 1001] });
         await wallet.sendBatch(batch);
         batch = [];
         for (let i = 200; i > 0; i--)
-          batch.push(['BID', name, i * 1002, i * 1002]);
+          batch.push({ type: 'BID', args: [name, i * 1002, i * 1002] });
         await wallet.sendBatch(batch);
         batch = [];
         for (let i = 150; i > 0; i--)
-          batch.push(['BID', name, i * 1003, i * 1003]);
+          batch.push({ type: 'BID', args: [name, i * 1003, i * 1003] });
         await wallet.sendBatch(batch);
 
         await mineBlocks(biddingPeriod);
@@ -1175,7 +1177,7 @@ describe('Wallet Auction', function() {
 
       it('should create batch just under weight limit', async () => {
         // Start with the batch we would normally make
-        const mtx = await wallet.createBatch([['REVEAL']]);
+        const mtx = await wallet.createBatch([{ type: 'REVEAL' }]);
 
         // Find a spendable coin
         const coins = await wallet.getCoins();
@@ -1213,12 +1215,12 @@ describe('Wallet Auction', function() {
 
       it('should REVEAL all in several batches', async () => {
         let reveals = 0;
-        const mtx1 = await wallet.createBatch([['REVEAL']]);
+        const mtx1 = await wallet.createBatch([{ type: 'REVEAL' }]);
         assert(mtx1.changeIndex >= 0);
         reveals += mtx1.outputs.length - 1;
         await wdb.addTX(mtx1.toTX());
 
-        const mtx2 = await wallet.createBatch([['REVEAL']]);
+        const mtx2 = await wallet.createBatch([{ type: 'REVEAL' }]);
         assert(mtx2.changeIndex >= 0);
         reveals += mtx2.outputs.length - 1;
         await wdb.addTX(mtx2.toTX());
@@ -1239,12 +1241,12 @@ describe('Wallet Auction', function() {
 
       it('should REDEEM all in several batches', async () => {
         let reveals = 0;
-        const mtx1 = await wallet.createBatch([['REDEEM']]);
+        const mtx1 = await wallet.createBatch([{ type: 'REDEEM' }]);
         assert(mtx1.changeIndex >= 0);
         reveals += mtx1.outputs.length - 1;
         await wdb.addTX(mtx1.toTX());
 
-        const mtx2 = await wallet.createBatch([['REDEEM']]);
+        const mtx2 = await wallet.createBatch([{ type: 'REDEEM' }]);
         assert(mtx2.changeIndex >= 0);
         reveals += mtx2.outputs.length - 1;
         await wdb.addTX(mtx2.toTX());
@@ -1292,7 +1294,7 @@ describe('Wallet Auction', function() {
       it('should not batch too many OPENs', async () => {
         const batch = [];
         for (let i = 0; i < consensus.MAX_BLOCK_OPENS + 1; i++)
-          batch.push(['OPEN', names[i]]);
+          batch.push({ type: 'OPEN', args: [names[i]] });
 
         await assert.rejects(
           wallet.createBatch(batch),
@@ -1305,7 +1307,7 @@ describe('Wallet Auction', function() {
         for (let i = 1; i <= 8; i++) {
           const batch = [];
           for (let j = 1; j <= 100; j++) {
-            batch.push(['OPEN', names[count++]]);
+            batch.push({ type: 'OPEN', args: [names[count++]] });
           }
           await wallet.sendBatch(batch);
           await mineBlocks(1);
@@ -1319,8 +1321,8 @@ describe('Wallet Auction', function() {
           const batch = [];
           for (let j = 1; j <= 100; j++) {
             batch.push(
-              ['BID', names[count], 10000, 10000],
-              ['BID', names[count++], 10000, 10000]
+              { type: 'BID', args: [names[count], 10000, 10000]},
+              { type: 'BID', args: [names[count++], 10000, 10000]}
             );
           }
           await wallet.sendBatch(batch);
@@ -1334,7 +1336,12 @@ describe('Wallet Auction', function() {
         let reveals = 0;
         for (;;) {
           try {
-            const tx = await wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]);
+            const tx = await wallet.sendBatch([
+              { type: 'REVEAL' },
+              { type: 'REDEEM' },
+              { type: 'RENEW' },
+              { type: 'FINALIZE' }
+            ]);
             reveals += tx.outputs.length - 1; // Don't count change output
           } catch (e) {
             assert.strictEqual(e.message, 'Nothing to do.');
@@ -1351,7 +1358,13 @@ describe('Wallet Auction', function() {
         let redeems = 0;
         for (;;) {
           try {
-            const tx = await wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]);
+            const tx = await wallet.sendBatch([
+              { type: 'REVEAL' },
+              { type: 'REDEEM' },
+              { type: 'RENEW' },
+              { type: 'FINALIZE' }
+            ]);
+
             redeems += tx.outputs.length - 1; // Don't count change output
           } catch (e) {
             assert.strictEqual(e.message, 'Nothing to do.');
@@ -1367,7 +1380,7 @@ describe('Wallet Auction', function() {
         for (let i = 1; i <= 8; i++) {
           const batch = [];
           for (let j = 1; j <= 100; j++) {
-            batch.push(['UPDATE', names[count++], new Resource()]);
+            batch.push({ type: 'UPDATE', args: [names[count++], new Resource()]});
           }
           await wallet.sendBatch(batch);
           await mineBlocks(1);
@@ -1390,7 +1403,7 @@ describe('Wallet Auction', function() {
       it('should not batch too many UPDATEs', async () => {
         const batch = [];
         for (let i = 0; i < consensus.MAX_BLOCK_UPDATES + 1; i++)
-          batch.push(['UPDATE', names[i], new Resource()]);
+          batch.push({ type: 'UPDATE', args: [names[i], new Resource()]});
 
         await assert.rejects(
           wallet.createBatch(batch),
@@ -1406,7 +1419,12 @@ describe('Wallet Auction', function() {
         );
 
         await assert.rejects(
-          wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]),
+          wallet.sendBatch([
+            { type: 'REVEAL' },
+            { type: 'REDEEM' },
+            { type: 'RENEW' },
+            { type: 'FINALIZE' }
+          ]),
           {message: 'Nothing to do.'}
         );
       });
@@ -1414,7 +1432,7 @@ describe('Wallet Auction', function() {
       it('should not batch too many RENEWs', async () => {
         const batch = [];
         for (let i = 0; i < consensus.MAX_BLOCK_RENEWALS + 1; i++)
-          batch.push(['RENEW', names[i]]);
+          batch.push({ type: 'RENEW', args: [names[i]]});
 
         await assert.rejects(
           wallet.createBatch(batch),
@@ -1427,7 +1445,12 @@ describe('Wallet Auction', function() {
 
         let renewals = 0;
         for (;;) {
-          const tx = await wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]);
+          const tx = await wallet.sendBatch([
+            { type: 'REVEAL' },
+            { type: 'REDEEM' },
+            { type: 'RENEW' },
+            { type: 'FINALIZE' }
+          ]);
           await mineBlocks(1);
 
           if (!renewals) {
@@ -1446,7 +1469,7 @@ describe('Wallet Auction', function() {
       it('should not batch too many TRANSFERs', async () => {
         const batch = [];
         for (const name of names)
-          batch.push(['TRANSFER', name, new Address()]);
+          batch.push({ type: 'TRANSFER', args: [name, new Address()]});
 
         await assert.rejects(
           wallet.createBatch(batch),
@@ -1460,7 +1483,7 @@ describe('Wallet Auction', function() {
         for (let i = 1; i <= 8; i++) {
           const batch = [];
           for (let j = 1; j <= 100; j++) {
-            batch.push(['TRANSFER', names[count++], addr]);
+            batch.push({ type: 'TRANSFER', args: [names[count++], addr]});
           }
           await wallet.sendBatch(batch);
           await mineBlocks(1);
@@ -1471,7 +1494,12 @@ describe('Wallet Auction', function() {
         await mineBlocks(network.names.lockupPeriod - 9);
 
         await assert.rejects(
-          wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]),
+          wallet.sendBatch([
+            { type: 'REVEAL' },
+            { type: 'REDEEM' },
+            { type: 'RENEW' },
+            { type: 'FINALIZE' }
+          ]),
           {message: 'Nothing to do.'}
         );
       });
@@ -1481,7 +1509,12 @@ describe('Wallet Auction', function() {
 
         let finalizes = 0;
         for (;;) {
-          const tx = await wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]);
+          const tx = await wallet.sendBatch([
+            { type: 'REVEAL' },
+            { type: 'REDEEM' },
+            { type: 'RENEW' },
+            { type: 'FINALIZE' }
+          ]);
           await mineBlocks(1);
 
           finalizes += tx.outputs.length - 1; // Don't count change output
@@ -1493,7 +1526,12 @@ describe('Wallet Auction', function() {
 
       it('should have nothing to do', async () => {
         await assert.rejects(
-          wallet.sendBatch([['REVEAL'], ['REDEEM'], ['RENEW'], ['FINALIZE']]),
+          wallet.sendBatch([
+            { type: 'REVEAL' },
+            { type: 'REDEEM' },
+            { type: 'RENEW' },
+            { type: 'FINALIZE' }
+          ]),
           {message: 'Nothing to do.'}
         );
       });
diff --git a/test/wallet-balance-test.js b/test/wallet-balance-test.js
index 065f8c99..6a0ae42b 100644
--- a/test/wallet-balance-test.js
+++ b/test/wallet-balance-test.js
@@ -565,8 +565,8 @@ describe('Wallet Balance', function() {
     const {nextAddr} = getAheadAddr(account, ahead);
 
     await primary.sendBatch([
-      ['OPEN', name1],
-      ['OPEN', name2]
+      { type: 'OPEN', args: [name1] },
+      { type: 'OPEN', args: [name2] }
     ]);
     await mineBlocks(openingPeriod);
 
@@ -574,8 +574,8 @@ describe('Wallet Balance', function() {
 
     // all three bids are there.
     const bidMTX = await wallet.createBatch([
-      ['BID', name1, BID_AMOUNT_1, BLIND_AMOUNT_1],
-      ['BID', name2, BID_AMOUNT_2, BLIND_AMOUNT_2]
+      { type: 'BID', args: [name1, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+      { type: 'BID', args: [name2, BID_AMOUNT_2, BLIND_AMOUNT_2] }
     ], txOpts);
 
     assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -604,16 +604,16 @@ describe('Wallet Balance', function() {
     await primary.sendReveal(name2);
 
     await wallet.sendBatch([
-      ['REVEAL', name1],
-      ['REVEAL', name2]
+      { type: 'REVEAL', args: [name1] },
+      { type: 'REVEAL', args: [name2] }
     ], txOpts);
 
     await mineBlocks(revealPeriod);
 
     if (register !== false) {
       await wallet.sendBatch([
-        ['UPDATE', name1, EMPTY_RS],
-        ['UPDATE', name2, EMPTY_RS]
+        { type: 'UPDATE', args: [name1, EMPTY_RS] },
+        { type: 'UPDATE', args: [name2, EMPTY_RS] }
       ], {
         hardFee: HARD_FEE
       });
@@ -1019,8 +1019,8 @@ describe('Wallet Balance', function() {
       const txOpts = { hardFee: HARD_FEE };
 
       const bidMTX = await wallet.createBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
 
       assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -1112,8 +1112,8 @@ describe('Wallet Balance', function() {
       const txOpts = { hardFee: HARD_FEE };
 
       const bidMTX = await primary.createBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
 
       assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -1209,8 +1209,8 @@ describe('Wallet Balance', function() {
       const addr2 = getAheadAddr(altAccount, ahead);
 
       const bidMTX = await wallet.createBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
 
       assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -1394,8 +1394,8 @@ describe('Wallet Balance', function() {
       await mineBlocks(openingPeriod);
 
       const bidMTX = await clone.createBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
 
       assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -1511,8 +1511,8 @@ describe('Wallet Balance', function() {
       await mineBlocks(openingPeriod);
 
       await wallet.sendBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
       await mineBlocks(biddingPeriod);
     };
@@ -1738,8 +1738,8 @@ describe('Wallet Balance', function() {
       await primary.sendOpen(name, false);
       await mineBlocks(openingPeriod);
       await primary.sendBatch([
-        ['BID', name, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ]);
       await mineBlocks(biddingPeriod);
     };
@@ -1840,8 +1840,8 @@ describe('Wallet Balance', function() {
       const addr1 = getAheadAddr(cloneAccount, ahead);
 
       await primary.sendBatch([
-        ['OPEN', name1],
-        ['OPEN', name2]
+        { type: 'OPEN', args: [name1] },
+        { type: 'OPEN', args: [name2] }
       ]);
       await mineBlocks(openingPeriod);
 
@@ -1853,8 +1853,8 @@ describe('Wallet Balance', function() {
 
       // all three bids are there.
       const bidMTX = await clone.createBatch([
-        ['BID', name1, BID_AMOUNT_1, BLIND_AMOUNT_1],
-        ['BID', name2, BID_AMOUNT_2, BLIND_AMOUNT_2]
+        { type: 'BID', args: [name1, BID_AMOUNT_1, BLIND_AMOUNT_1] },
+        { type: 'BID', args: [name2, BID_AMOUNT_2, BLIND_AMOUNT_2] }
       ], txOpts);
 
       assert.strictEqual(bidMTX.outputs[0].covenant.type, types.BID);
@@ -1873,8 +1873,8 @@ describe('Wallet Balance', function() {
       await primary.sendReveal(name2);
 
       await clone.sendBatch([
-        ['REVEAL', name1],
-        ['REVEAL', name2]
+        { type: 'REVEAL', args: [name1] },
+        { type: 'REVEAL', args: [name2] }
       ], txOpts);
 
       await mineBlocks(revealPeriod + 1);
@@ -1882,8 +1882,8 @@ describe('Wallet Balance', function() {
 
     const sendRedeems = async (wallet, clone, ahead) => {
       await clone.sendBatch([
-        ['REDEEM', name1],
-        ['REDEEM', name2]
+        { type: 'REDEEM', args: [name1] },
+        { type: 'REDEEM', args: [name2] }
       ], {
         hardFee: HARD_FEE
       });
@@ -1984,8 +1984,8 @@ describe('Wallet Balance', function() {
 
     const sendRedeems = async (wallet, clone, ahead) => {
       await clone.sendBatch([
-        ['UPDATE', name1, EMPTY_RS],
-        ['UPDATE', name2, EMPTY_RS]
+        { type: 'UPDATE', args: [name1, EMPTY_RS] },
+        { type: 'UPDATE', args: [name2, EMPTY_RS] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2124,8 +2124,8 @@ describe('Wallet Balance', function() {
 
     const sendUpdates = async (wallet, clone) => {
       await clone.sendBatch([
-        ['UPDATE', name1, EMPTY_RS],
-        ['UPDATE', name2, EMPTY_RS]
+        { type: 'UPDATE', args: [name1, EMPTY_RS] },
+        { type: 'UPDATE', args: [name2, EMPTY_RS] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2165,8 +2165,8 @@ describe('Wallet Balance', function() {
 
     const sendRevokes = async (wallet, clone) => {
       await clone.sendBatch([
-        ['REVOKE', name1],
-        ['REVOKE', name2]
+        { type: 'REVOKE', args: [name1] },
+        { type: 'REVOKE', args: [name2] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2205,8 +2205,8 @@ describe('Wallet Balance', function() {
     const sendRenews = async (wallet, clone) => {
       await mineBlocks(treeInterval);
       await clone.sendBatch([
-        ['RENEW', name1],
-        ['RENEW', name2]
+        { type: 'RENEW', args: [name1] },
+        { type: 'RENEW', args: [name2] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2244,8 +2244,8 @@ describe('Wallet Balance', function() {
 
     const sendTransfers = async (wallet, clone) => {
       await clone.sendBatch([
-        ['TRANSFER', name1, await primary.receiveAddress()],
-        ['TRANSFER', name2, await primary.receiveAddress()]
+        { type: 'TRANSFER', args: [name1, await primary.receiveAddress()] },
+        { type: 'TRANSFER', args: [name2, await primary.receiveAddress()] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2281,8 +2281,8 @@ describe('Wallet Balance', function() {
       name2 = names[1];
 
       await clone.sendBatch([
-        ['TRANSFER', name1, await primary.receiveAddress()],
-        ['TRANSFER', name2, await primary.receiveAddress()]
+        { type: 'TRANSFER', args: [name1, await primary.receiveAddress()] },
+        { type: 'TRANSFER', args: [name2, await primary.receiveAddress()] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2292,8 +2292,8 @@ describe('Wallet Balance', function() {
 
     const sendFinalizes = async (wallet, clone) => {
       await clone.sendBatch([
-        ['FINALIZE', name1],
-        ['FINALIZE', name2]
+        { type: 'FINALIZE', args: [name1] },
+        { type: 'FINALIZE', args: [name2] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2383,8 +2383,8 @@ describe('Wallet Balance', function() {
       name2 = names[1];
 
       await clone.sendBatch([
-        ['TRANSFER', name1, recv],
-        ['TRANSFER', name2, nextAddr]
+        { type: 'TRANSFER', args: [name1, recv] },
+        { type: 'TRANSFER', args: [name2, nextAddr] }
       ], {
         hardFee: HARD_FEE
       });
@@ -2394,8 +2394,8 @@ describe('Wallet Balance', function() {
 
     const sendFinalizes = async (wallet, clone) => {
       await clone.sendBatch([
-        ['FINALIZE', name1],
-        ['FINALIZE', name2]
+        { type: 'FINALIZE', args: [name1] },
+        { type: 'FINALIZE', args: [name2] }
       ], {
         hardFee: HARD_FEE
       });
diff --git a/test/wallet-importnonce-test.js b/test/wallet-importnonce-test.js
index 85c6d2b0..8ce9c326 100644
--- a/test/wallet-importnonce-test.js
+++ b/test/wallet-importnonce-test.js
@@ -75,8 +75,8 @@ describe('Wallet Import Nonce', function () {
 
   it('should bid with sendbatch', async () => {
     const batch = [
-      ['BID', NAME, BIDS[1].value, BIDS[1].lockup],
-      ['BID', NAME, BIDS[2].value, BIDS[2].lockup]
+      { type: 'BID', args: [NAME, BIDS[1].value, BIDS[1].lockup]},
+      { type: 'BID', args: [NAME, BIDS[2].value, BIDS[2].lockup]}
     ];
 
     const bidTx = await walletA.sendBatch(batch);