diff --git a/cli/backup.go b/cli/backup.go
index 4d88d4bbc..3cb44718f 100644
--- a/cli/backup.go
+++ b/cli/backup.go
@@ -114,7 +114,7 @@ this command must be within this base path`,
 		},
 		ArgsUsage: "[backup file path]",
 		Action: func(cctx *cli.Context) error {
-			if cctx.Args().Len() != 1 {
+			if cctx.NArg() != 1 {
 				return xerrors.Errorf("expected 1 argument")
 			}
 
diff --git a/cli/chain.go b/cli/chain.go
index 39f1608f5..80df5655b 100644
--- a/cli/chain.go
+++ b/cli/chain.go
@@ -946,7 +946,7 @@ var ChainBisectCmd = &cli.Command{
 		defer closer()
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() < 4 {
+		if cctx.NArg() < 4 {
 			return xerrors.New("need at least 4 args")
 		}
 
@@ -1312,7 +1312,7 @@ var chainDecodeParamsCmd = &cli.Command{
 		defer closer()
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return ShowHelp(cctx, fmt.Errorf("incorrect number of arguments"))
 		}
 
@@ -1391,7 +1391,7 @@ var chainEncodeParamsCmd = &cli.Command{
 	Action: func(cctx *cli.Context) error {
 		afmt := NewAppFmt(cctx.App)
 
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return ShowHelp(cctx, fmt.Errorf("incorrect number of arguments"))
 		}
 
diff --git a/cli/client.go b/cli/client.go
index 5f2342b2b..577a8e840 100644
--- a/cli/client.go
+++ b/cli/client.go
@@ -212,7 +212,7 @@ var clientCommPCmd = &cli.Command{
 		defer closer()
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("usage: commP <inputPath>")
 		}
 
@@ -245,7 +245,7 @@ var clientCarGenCmd = &cli.Command{
 		defer closer()
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return fmt.Errorf("usage: generate-car <inputPath> <outputPath>")
 		}
 
diff --git a/cli/filplus.go b/cli/filplus.go
index 66de32d0c..7ac4f0d58 100644
--- a/cli/filplus.go
+++ b/cli/filplus.go
@@ -61,7 +61,7 @@ var filplusVerifyClientCmd = &cli.Command{
 			return err
 		}
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return fmt.Errorf("must specify two arguments: address and allowance")
 		}
 
@@ -289,7 +289,7 @@ var filplusSignRemoveDataCapProposal = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return fmt.Errorf("must specify three arguments: notary address, client address, and allowance to remove")
 		}
 
diff --git a/cli/mpool.go b/cli/mpool.go
index 1410814b5..c8003092d 100644
--- a/cli/mpool.go
+++ b/cli/mpool.go
@@ -404,7 +404,7 @@ var MpoolReplaceCmd = &cli.Command{
 
 		var from address.Address
 		var nonce uint64
-		switch cctx.Args().Len() {
+		switch cctx.NArg() {
 		case 1:
 			mcid, err := cid.Decode(cctx.Args().First())
 			if err != nil {
@@ -610,7 +610,7 @@ var MpoolConfig = &cli.Command{
 	Usage:     "get or set current mpool configuration",
 	ArgsUsage: "[new-config]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() > 1 {
+		if cctx.NArg() > 1 {
 			return cli.ShowCommandHelp(cctx, cctx.Command.Name)
 		}
 
@@ -624,7 +624,7 @@ var MpoolConfig = &cli.Command{
 
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			cfg, err := api.MpoolGetConfig(ctx)
 			if err != nil {
 				return err
diff --git a/cli/multisig.go b/cli/multisig.go
index 67c833397..7a86c2d87 100644
--- a/cli/multisig.go
+++ b/cli/multisig.go
@@ -88,7 +88,7 @@ var msigCreateCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			return ShowHelp(cctx, fmt.Errorf("multisigs must have at least one signer"))
 		}
 
@@ -365,11 +365,11 @@ var msigProposeCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 3 {
+		if cctx.NArg() < 3 {
 			return ShowHelp(cctx, fmt.Errorf("must pass at least multisig address, destination, and value"))
 		}
 
-		if cctx.Args().Len() > 3 && cctx.Args().Len() != 5 {
+		if cctx.NArg() > 3 && cctx.NArg() != 5 {
 			return ShowHelp(cctx, fmt.Errorf("must either pass three or five arguments"))
 		}
 
@@ -399,7 +399,7 @@ var msigProposeCmd = &cli.Command{
 
 		var method uint64
 		var params []byte
-		if cctx.Args().Len() == 5 {
+		if cctx.NArg() == 5 {
 			m, err := strconv.ParseUint(cctx.Args().Get(3), 10, 64)
 			if err != nil {
 				return err
@@ -487,15 +487,15 @@ var msigApproveCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass at least multisig address and message ID"))
 		}
 
-		if cctx.Args().Len() > 2 && cctx.Args().Len() < 5 {
+		if cctx.NArg() > 2 && cctx.NArg() < 5 {
 			return ShowHelp(cctx, fmt.Errorf("usage: msig approve <msig addr> <message ID> <proposer address> <desination> <value>"))
 		}
 
-		if cctx.Args().Len() > 5 && cctx.Args().Len() != 7 {
+		if cctx.NArg() > 5 && cctx.NArg() != 7 {
 			return ShowHelp(cctx, fmt.Errorf("usage: msig approve <msig addr> <message ID> <proposer address> <desination> <value> [ <method> <params> ]"))
 		}
 
@@ -534,7 +534,7 @@ var msigApproveCmd = &cli.Command{
 		}
 
 		var msgCid cid.Cid
-		if cctx.Args().Len() == 2 {
+		if cctx.NArg() == 2 {
 			proto, err := api.MsigApprove(ctx, msig, txid, from)
 			if err != nil {
 				return err
@@ -571,7 +571,7 @@ var msigApproveCmd = &cli.Command{
 
 			var method uint64
 			var params []byte
-			if cctx.Args().Len() == 7 {
+			if cctx.NArg() == 7 {
 				m, err := strconv.ParseUint(cctx.Args().Get(5), 10, 64)
 				if err != nil {
 					return err
@@ -624,15 +624,15 @@ var msigCancelCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass at least multisig address and message ID"))
 		}
 
-		if cctx.Args().Len() > 2 && cctx.Args().Len() < 4 {
+		if cctx.NArg() > 2 && cctx.NArg() < 4 {
 			return ShowHelp(cctx, fmt.Errorf("usage: msig cancel <msig addr> <message ID> <desination> <value>"))
 		}
 
-		if cctx.Args().Len() > 4 && cctx.Args().Len() != 6 {
+		if cctx.NArg() > 4 && cctx.NArg() != 6 {
 			return ShowHelp(cctx, fmt.Errorf("usage: msig cancel <msig addr> <message ID> <desination> <value> [ <method> <params> ]"))
 		}
 
@@ -671,7 +671,7 @@ var msigCancelCmd = &cli.Command{
 		}
 
 		var msgCid cid.Cid
-		if cctx.Args().Len() == 2 {
+		if cctx.NArg() == 2 {
 			proto, err := api.MsigCancel(ctx, msig, txid, from)
 			if err != nil {
 				return err
@@ -696,7 +696,7 @@ var msigCancelCmd = &cli.Command{
 
 			var method uint64
 			var params []byte
-			if cctx.Args().Len() == 6 {
+			if cctx.NArg() == 6 {
 				m, err := strconv.ParseUint(cctx.Args().Get(4), 10, 64)
 				if err != nil {
 					return err
@@ -753,7 +753,7 @@ var msigRemoveProposeCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address and signer address"))
 		}
 
@@ -840,7 +840,7 @@ var msigAddProposeCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address and signer address"))
 		}
 
@@ -949,7 +949,7 @@ var msigAddApproveCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 5 {
+		if cctx.NArg() != 5 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, proposer address, transaction id, new signer address, whether to increase threshold"))
 		}
 
@@ -1040,7 +1040,7 @@ var msigAddCancelCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 4 {
+		if cctx.NArg() != 4 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, transaction id, new signer address, whether to increase threshold"))
 		}
 
@@ -1126,7 +1126,7 @@ var msigSwapProposeCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, old signer address, new signer address"))
 		}
 
@@ -1207,7 +1207,7 @@ var msigSwapApproveCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 5 {
+		if cctx.NArg() != 5 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, proposer address, transaction id, old signer address, new signer address"))
 		}
 
@@ -1298,7 +1298,7 @@ var msigSwapCancelCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 4 {
+		if cctx.NArg() != 4 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, transaction id, old signer address, new signer address"))
 		}
 
@@ -1384,7 +1384,7 @@ var msigLockProposeCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 4 {
+		if cctx.NArg() != 4 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, start epoch, unlock duration, and amount"))
 		}
 
@@ -1480,7 +1480,7 @@ var msigLockApproveCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 6 {
+		if cctx.NArg() != 6 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, proposer address, tx id, start epoch, unlock duration, and amount"))
 		}
 
@@ -1586,7 +1586,7 @@ var msigLockCancelCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 5 {
+		if cctx.NArg() != 5 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address, tx id, start epoch, unlock duration, and amount"))
 		}
 
@@ -1693,7 +1693,7 @@ var msigVestedCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address"))
 		}
 
@@ -1749,7 +1749,7 @@ var msigProposeThresholdCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass multisig address and new threshold value"))
 		}
 
diff --git a/cli/net.go b/cli/net.go
index 5a141e52d..c1ca1ce18 100644
--- a/cli/net.go
+++ b/cli/net.go
@@ -141,7 +141,7 @@ var NetPing = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("please provide a peerID")
 		}
 
diff --git a/cli/paych.go b/cli/paych.go
index 8277e3123..263aa7f34 100644
--- a/cli/paych.go
+++ b/cli/paych.go
@@ -50,7 +50,7 @@ var paychAddFundsCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return ShowHelp(cctx, fmt.Errorf("must pass three arguments: <from> <to> <available funds>"))
 		}
 
@@ -112,7 +112,7 @@ var paychStatusByFromToCmd = &cli.Command{
 	Usage:     "Show the status of an active outbound payment channel by from/to addresses",
 	ArgsUsage: "[fromAddress toAddress]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass two arguments: <from address> <to address>"))
 		}
 		ctx := ReqContext(cctx)
@@ -148,7 +148,7 @@ var paychStatusCmd = &cli.Command{
 	Usage:     "Show the status of an outbound payment channel",
 	ArgsUsage: "[channelAddress]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return ShowHelp(cctx, fmt.Errorf("must pass an argument: <channel address>"))
 		}
 		ctx := ReqContext(cctx)
@@ -260,7 +260,7 @@ var paychSettleCmd = &cli.Command{
 	Usage:     "Settle a payment channel",
 	ArgsUsage: "[channelAddress]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must pass payment channel address")
 		}
 
@@ -300,7 +300,7 @@ var paychCloseCmd = &cli.Command{
 	Usage:     "Collect funds for a payment channel",
 	ArgsUsage: "[channelAddress]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must pass payment channel address")
 		}
 
@@ -360,7 +360,7 @@ var paychVoucherCreateCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass two arguments: <channel> <amount>"))
 		}
 
@@ -408,7 +408,7 @@ var paychVoucherCheckCmd = &cli.Command{
 	Usage:     "Check validity of payment channel voucher",
 	ArgsUsage: "[channelAddress voucher]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass payment channel address and voucher to validate"))
 		}
 
@@ -444,7 +444,7 @@ var paychVoucherAddCmd = &cli.Command{
 	Usage:     "Add payment channel voucher to local datastore",
 	ArgsUsage: "[channelAddress voucher]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass payment channel address and voucher"))
 		}
 
@@ -486,7 +486,7 @@ var paychVoucherListCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return ShowHelp(cctx, fmt.Errorf("must pass payment channel address"))
 		}
 
@@ -531,7 +531,7 @@ var paychVoucherBestSpendableCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return ShowHelp(cctx, fmt.Errorf("must pass payment channel address"))
 		}
 
@@ -602,7 +602,7 @@ var paychVoucherSubmitCmd = &cli.Command{
 	Usage:     "Submit voucher to chain to update payment channel state",
 	ArgsUsage: "[channelAddress voucher]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("must pass payment channel address and voucher"))
 		}
 
diff --git a/cli/send.go b/cli/send.go
index b5bfd3eb0..b2471e7cd 100644
--- a/cli/send.go
+++ b/cli/send.go
@@ -67,7 +67,7 @@ var sendCmd = &cli.Command{
 			fmt.Println("'force' flag is deprecated, use global flag 'force-send'")
 		}
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return ShowHelp(cctx, fmt.Errorf("'send' expects two arguments, target and amount"))
 		}
 
diff --git a/cli/state.go b/cli/state.go
index bea7ed0df..e4afc6915 100644
--- a/cli/state.go
+++ b/cli/state.go
@@ -504,7 +504,7 @@ var StateReplayCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			fmt.Println("must provide cid of message to replay")
 			return nil
 		}
@@ -1580,7 +1580,7 @@ var StateCallCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return fmt.Errorf("must specify at least actor and method to invoke")
 		}
 
@@ -1619,7 +1619,7 @@ var StateCallCmd = &cli.Command{
 
 		var params []byte
 		// If params were passed in, decode them
-		if cctx.Args().Len() > 2 {
+		if cctx.NArg() > 2 {
 			switch cctx.String("encoding") {
 			case "base64":
 				params, err = base64.StdEncoding.DecodeString(cctx.Args().Get(2))
@@ -1743,7 +1743,7 @@ var StateSectorCmd = &cli.Command{
 
 		ctx := ReqContext(cctx)
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return xerrors.Errorf("expected 2 params: minerAddress and sectorNumber")
 		}
 
diff --git a/cmd/lotus-bench/simple.go b/cmd/lotus-bench/simple.go
index b999cd277..87e2c3bc0 100644
--- a/cmd/lotus-bench/simple.go
+++ b/cmd/lotus-bench/simple.go
@@ -959,7 +959,7 @@ var simpleProveReplicaUpdate2 = &cli.Command{
 }
 
 func ParsePieceInfos(cctx *cli.Context, firstArg int) ([]abi.PieceInfo, error) {
-	args := cctx.Args().Len() - firstArg
+	args := cctx.NArg() - firstArg
 	if args%2 != 0 {
 		return nil, xerrors.Errorf("piece info argunemts need to be supplied in pairs")
 	}
diff --git a/cmd/lotus-miner/init_restore.go b/cmd/lotus-miner/init_restore.go
index a54146fb2..9d7f977b6 100644
--- a/cmd/lotus-miner/init_restore.go
+++ b/cmd/lotus-miner/init_restore.go
@@ -96,7 +96,7 @@ var restoreCmd = &cli.Command{
 }
 
 func restore(ctx context.Context, cctx *cli.Context, targetPath string, strConfig *paths.StorageConfig, manageConfig func(*config.StorageMiner) error, after func(api lapi.FullNode, addr address.Address, peerid peer.ID, mi api.MinerInfo) error) error {
-	if cctx.Args().Len() != 1 {
+	if cctx.NArg() != 1 {
 		return xerrors.Errorf("expected 1 argument")
 	}
 
diff --git a/cmd/lotus-miner/market.go b/cmd/lotus-miner/market.go
index 37d252efa..78b68214e 100644
--- a/cmd/lotus-miner/market.go
+++ b/cmd/lotus-miner/market.go
@@ -370,7 +370,7 @@ var dealsImportDataCmd = &cli.Command{
 
 		ctx := lcli.DaemonContext(cctx)
 
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return fmt.Errorf("must specify proposal CID and file path")
 		}
 
@@ -617,7 +617,7 @@ var setSealDurationCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass duration in minutes")
 		}
 
diff --git a/cmd/lotus-miner/proving.go b/cmd/lotus-miner/proving.go
index 85bc48e78..bbb744680 100644
--- a/cmd/lotus-miner/proving.go
+++ b/cmd/lotus-miner/proving.go
@@ -314,7 +314,7 @@ var provingDeadlineInfoCmd = &cli.Command{
 	ArgsUsage: "<deadlineIdx>",
 	Action: func(cctx *cli.Context) error {
 
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass deadline index")
 		}
 
@@ -461,7 +461,7 @@ var provingCheckProvableCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass deadline index")
 		}
 
@@ -616,7 +616,7 @@ var provingComputeWindowPoStCmd = &cli.Command{
 It will not send any messages to the chain.`,
 	ArgsUsage: "[deadline index]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass deadline index")
 		}
 
@@ -661,7 +661,7 @@ var provingRecoverFaultsCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			return xerrors.Errorf("must pass at least 1 sector number")
 		}
 
diff --git a/cmd/lotus-miner/sealing.go b/cmd/lotus-miner/sealing.go
index 970f54a55..334266c79 100644
--- a/cmd/lotus-miner/sealing.go
+++ b/cmd/lotus-miner/sealing.go
@@ -372,7 +372,7 @@ var sealingAbortCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("expected 1 argument")
 		}
 
@@ -430,7 +430,7 @@ var sealingDataCidCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 || cctx.Args().Len() > 2 {
+		if cctx.NArg() < 1 || cctx.NArg() > 2 {
 			return xerrors.Errorf("expected 1 or 2 arguments")
 		}
 
@@ -484,7 +484,7 @@ var sealingDataCidCmd = &cli.Command{
 		}
 
 		var psize abi.PaddedPieceSize
-		if cctx.Args().Len() == 2 {
+		if cctx.NArg() == 2 {
 			rps, err := humanize.ParseBytes(cctx.Args().Get(1))
 			if err != nil {
 				return xerrors.Errorf("parsing piece size: %w", err)
diff --git a/cmd/lotus-miner/sectors.go b/cmd/lotus-miner/sectors.go
index 45a1256aa..336a06f52 100644
--- a/cmd/lotus-miner/sectors.go
+++ b/cmd/lotus-miner/sectors.go
@@ -1378,7 +1378,7 @@ var sectorsTerminateCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass sector number")
 		}
 
@@ -1488,7 +1488,7 @@ var sectorsRemoveCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass sector number")
 		}
 
@@ -1506,7 +1506,7 @@ var sectorsSnapUpCmd = &cli.Command{
 	Usage:     "Mark a committed capacity sector to be filled with deals",
 	ArgsUsage: "<sectorNum>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return lcli.ShowHelp(cctx, xerrors.Errorf("must pass sector number"))
 		}
 
@@ -1550,7 +1550,7 @@ var sectorsSnapAbortCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return lcli.ShowHelp(cctx, xerrors.Errorf("must pass sector number"))
 		}
 
@@ -1587,7 +1587,7 @@ var sectorsStartSealCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass sector number")
 		}
 
@@ -1611,7 +1611,7 @@ var sectorsSealDelayCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("must pass duration in minutes")
 		}
 
@@ -1714,7 +1714,7 @@ var sectorsUpdateCmd = &cli.Command{
 		}
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return xerrors.Errorf("must pass sector number and new state")
 		}
 
@@ -2310,7 +2310,7 @@ var sectorsNumbersReserveCmd = &cli.Command{
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return xerrors.Errorf("expected 2 arguments: [reservation name] [reserved ranges]")
 		}
 
@@ -2335,7 +2335,7 @@ var sectorsNumbersFreeCmd = &cli.Command{
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
 
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("expected 1 argument: [reservation name]")
 		}
 
diff --git a/cmd/lotus-seed/genesis.go b/cmd/lotus-seed/genesis.go
index 9f0a8f7dc..df2a91ad9 100644
--- a/cmd/lotus-seed/genesis.go
+++ b/cmd/lotus-seed/genesis.go
@@ -93,7 +93,7 @@ var genesisAddMinerCmd = &cli.Command{
 	Description: "add genesis miner",
 	Flags:       []cli.Flag{},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return xerrors.New("seed genesis add-miner [genesis.json] [preseal.json]")
 		}
 
@@ -181,7 +181,7 @@ type GenAccountEntry struct {
 var genesisAddMsigsCmd = &cli.Command{
 	Name: "add-msigs",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 2 {
+		if cctx.NArg() < 2 {
 			return fmt.Errorf("must specify template file and csv file with accounts")
 		}
 
@@ -329,7 +329,7 @@ var genesisSetVRKCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must specify template file")
 		}
 
@@ -425,7 +425,7 @@ var genesisSetRemainderCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must specify template file")
 		}
 
@@ -519,7 +519,7 @@ var genesisSetActorVersionCmd = &cli.Command{
 	},
 	ArgsUsage: "<genesisFile>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must specify genesis file")
 		}
 
@@ -597,7 +597,7 @@ var genesisSetVRKSignersCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return fmt.Errorf("must specify template file")
 		}
 
diff --git a/cmd/lotus-shed/base16.go b/cmd/lotus-shed/base16.go
index adfdfeddb..a5d384815 100644
--- a/cmd/lotus-shed/base16.go
+++ b/cmd/lotus-shed/base16.go
@@ -24,7 +24,7 @@ var base16Cmd = &cli.Command{
 	Action: func(cctx *cli.Context) error {
 		var input io.Reader
 
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = os.Stdin
 		} else {
 			input = strings.NewReader(cctx.Args().First())
diff --git a/cmd/lotus-shed/base32.go b/cmd/lotus-shed/base32.go
index 4ca177316..66e180ddc 100644
--- a/cmd/lotus-shed/base32.go
+++ b/cmd/lotus-shed/base32.go
@@ -24,7 +24,7 @@ var base32Cmd = &cli.Command{
 	Action: func(cctx *cli.Context) error {
 		var input io.Reader
 
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = os.Stdin
 		} else {
 			input = strings.NewReader(cctx.Args().First())
diff --git a/cmd/lotus-shed/base64.go b/cmd/lotus-shed/base64.go
index 9143a6a19..cacc60152 100644
--- a/cmd/lotus-shed/base64.go
+++ b/cmd/lotus-shed/base64.go
@@ -32,7 +32,7 @@ var base64Cmd = &cli.Command{
 	Action: func(cctx *cli.Context) error {
 		var input io.Reader
 
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = os.Stdin
 		} else {
 			input = strings.NewReader(cctx.Args().First())
diff --git a/cmd/lotus-shed/consensus.go b/cmd/lotus-shed/consensus.go
index f6bd7688f..197de56f9 100644
--- a/cmd/lotus-shed/consensus.go
+++ b/cmd/lotus-shed/consensus.go
@@ -84,7 +84,7 @@ var consensusCheckCmd = &cli.Command{
 		filePath := cctx.Args().First()
 
 		var input *bufio.Reader
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = bufio.NewReader(os.Stdin)
 		} else {
 			var err error
diff --git a/cmd/lotus-shed/datastore.go b/cmd/lotus-shed/datastore.go
index 7cdb2b1e6..cd650d122 100644
--- a/cmd/lotus-shed/datastore.go
+++ b/cmd/lotus-shed/datastore.go
@@ -171,7 +171,7 @@ var datastoreBackupStatCmd = &cli.Command{
 	Description: "validate and print info about datastore backup",
 	ArgsUsage:   "[file]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("expected 1 argument")
 		}
 
@@ -220,7 +220,7 @@ var datastoreBackupListCmd = &cli.Command{
 	},
 	ArgsUsage: "[file]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("expected 1 argument")
 		}
 
diff --git a/cmd/lotus-shed/export-car.go b/cmd/lotus-shed/export-car.go
index 97e4fb6c6..b33b2b4ec 100644
--- a/cmd/lotus-shed/export-car.go
+++ b/cmd/lotus-shed/export-car.go
@@ -38,7 +38,7 @@ var exportCarCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return lcli.ShowHelp(cctx, fmt.Errorf("must specify file name and object"))
 		}
 
diff --git a/cmd/lotus-shed/keyinfo.go b/cmd/lotus-shed/keyinfo.go
index 135b5bc9d..373964dc6 100644
--- a/cmd/lotus-shed/keyinfo.go
+++ b/cmd/lotus-shed/keyinfo.go
@@ -149,7 +149,7 @@ var keyinfoImportCmd = &cli.Command{
 		flagRepo := cctx.String("repo")
 
 		var input io.Reader
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = os.Stdin
 		} else {
 			var err error
@@ -261,7 +261,7 @@ var keyinfoInfoCmd = &cli.Command{
 		format := cctx.String("format")
 
 		var input io.Reader
-		if cctx.Args().Len() == 0 {
+		if cctx.NArg() == 0 {
 			input = os.Stdin
 		} else {
 			var err error
diff --git a/cmd/lotus-shed/miner.go b/cmd/lotus-shed/miner.go
index a23a44410..0d925336d 100644
--- a/cmd/lotus-shed/miner.go
+++ b/cmd/lotus-shed/miner.go
@@ -135,7 +135,7 @@ var minerCreateCmd = &cli.Command{
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
 
-		if cctx.Args().Len() != 4 {
+		if cctx.NArg() != 4 {
 			return xerrors.Errorf("expected 4 args (sender owner worker sectorSize)")
 		}
 
@@ -273,7 +273,7 @@ var minerUnpackInfoCmd = &cli.Command{
 	Usage:     "unpack miner info all dump",
 	ArgsUsage: "[allinfo.txt] [dir]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return xerrors.Errorf("expected 2 args")
 		}
 
diff --git a/cmd/lotus-shed/msg.go b/cmd/lotus-shed/msg.go
index 49412948c..34b260961 100644
--- a/cmd/lotus-shed/msg.go
+++ b/cmd/lotus-shed/msg.go
@@ -27,7 +27,7 @@ var msgCmd = &cli.Command{
 	Usage:     "Translate message between various formats",
 	ArgsUsage: "Message in any form",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("expected 1 argument")
 		}
 
diff --git a/cmd/lotus-shed/proofs.go b/cmd/lotus-shed/proofs.go
index 65cf04918..752469778 100644
--- a/cmd/lotus-shed/proofs.go
+++ b/cmd/lotus-shed/proofs.go
@@ -42,7 +42,7 @@ var verifySealProofCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return fmt.Errorf("must specify commR, commD, and proof to verify")
 		}
 
diff --git a/cmd/lotus-shed/rpc.go b/cmd/lotus-shed/rpc.go
index b253304a1..82412e317 100644
--- a/cmd/lotus-shed/rpc.go
+++ b/cmd/lotus-shed/rpc.go
@@ -112,7 +112,7 @@ var rpcCmd = &cli.Command{
 		}
 
 		if cctx.Args().Present() {
-			if cctx.Args().Len() > 2 {
+			if cctx.NArg() > 2 {
 				return xerrors.Errorf("expected 1 or 2 arguments: method [params]")
 			}
 
diff --git a/cmd/lotus-shed/sectors.go b/cmd/lotus-shed/sectors.go
index 0332b4ba3..39e17f045 100644
--- a/cmd/lotus-shed/sectors.go
+++ b/cmd/lotus-shed/sectors.go
@@ -64,7 +64,7 @@ var terminateSectorCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			return fmt.Errorf("at least one sector must be specified")
 		}
 
@@ -200,7 +200,7 @@ var terminateSectorPenaltyEstimationCmd = &cli.Command{
 		},
 	},
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			return fmt.Errorf("at least one sector must be specified")
 		}
 
diff --git a/cmd/lotus-shed/signatures.go b/cmd/lotus-shed/signatures.go
index 0f43503f6..d06ae56ea 100644
--- a/cmd/lotus-shed/signatures.go
+++ b/cmd/lotus-shed/signatures.go
@@ -31,7 +31,7 @@ var sigsVerifyBlsMsgsCmd = &cli.Command{
 	Description: "given a block, verifies the bls signature of the messages in the block",
 	Usage:       "<blockCid>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 1 {
+		if cctx.NArg() != 1 {
 			return xerrors.Errorf("usage: <blockCid>")
 		}
 
@@ -101,7 +101,7 @@ var sigsVerifyVoteCmd = &cli.Command{
 	Usage:       "<FIPnumber> <signingAddress> <signature>",
 	Action: func(cctx *cli.Context) error {
 
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return xerrors.Errorf("usage: verify-vote <FIPnumber> <signingAddress> <signature>")
 		}
 
diff --git a/cmd/lotus-shed/stateroot-stats.go b/cmd/lotus-shed/stateroot-stats.go
index 7937b3ccd..f429c4e64 100644
--- a/cmd/lotus-shed/stateroot-stats.go
+++ b/cmd/lotus-shed/stateroot-stats.go
@@ -174,8 +174,8 @@ var staterootStatCmd = &cli.Command{
 		}
 
 		outcap := 10
-		if cctx.Args().Len() > outcap {
-			outcap = cctx.Args().Len()
+		if cctx.NArg() > outcap {
+			outcap = cctx.NArg()
 		}
 		if len(infos) < outcap {
 			outcap = len(infos)
diff --git a/cmd/lotus-shed/sync.go b/cmd/lotus-shed/sync.go
index 397e76da3..915ef38d0 100644
--- a/cmd/lotus-shed/sync.go
+++ b/cmd/lotus-shed/sync.go
@@ -38,7 +38,7 @@ var syncValidateCmd = &cli.Command{
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
 
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			fmt.Println("usage: <blockCid1> <blockCid2>...")
 			fmt.Println("At least one block cid must be provided")
 			return nil
@@ -75,7 +75,7 @@ var syncScrapePowerCmd = &cli.Command{
 	Usage:     "given a height and a tipset, reports what percentage of mining power had a winning ticket between the tipset and height",
 	ArgsUsage: "[height tipsetkey]",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			fmt.Println("usage: <height> [blockCid1 blockCid2...]")
 			fmt.Println("Any CIDs passed after the height will be used as the tipset key")
 			fmt.Println("If no block CIDs are provided, chain head will be used")
@@ -90,7 +90,7 @@ var syncScrapePowerCmd = &cli.Command{
 		defer closer()
 		ctx := lcli.ReqContext(cctx)
 
-		if cctx.Args().Len() < 1 {
+		if cctx.NArg() < 1 {
 			fmt.Println("usage: <blockCid1> <blockCid2>...")
 			fmt.Println("At least one block cid must be provided")
 			return nil
diff --git a/cmd/lotus-shed/verifreg.go b/cmd/lotus-shed/verifreg.go
index 2731ea11b..97392b2f0 100644
--- a/cmd/lotus-shed/verifreg.go
+++ b/cmd/lotus-shed/verifreg.go
@@ -46,7 +46,7 @@ var verifRegAddVerifierFromMsigCmd = &cli.Command{
 	Usage:     "make a given account a verifier",
 	ArgsUsage: "<message sender> <new verifier> <allowance>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return fmt.Errorf("must specify three arguments: sender, verifier, and allowance")
 		}
 
@@ -119,7 +119,7 @@ var verifRegAddVerifierFromAccountCmd = &cli.Command{
 	Usage:     "make a given account a verifier",
 	ArgsUsage: "<verifier root key> <new verifier> <allowance>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 3 {
+		if cctx.NArg() != 3 {
 			return fmt.Errorf("must specify three arguments: sender, verifier, and allowance")
 		}
 
@@ -201,7 +201,7 @@ var verifRegVerifyClientCmd = &cli.Command{
 			return err
 		}
 
-		if cctx.Args().Len() != 2 {
+		if cctx.NArg() != 2 {
 			return fmt.Errorf("must specify two arguments: address and allowance")
 		}
 
@@ -418,7 +418,7 @@ var verifRegRemoveVerifiedClientDataCapCmd = &cli.Command{
 	Usage:     "Remove data cap from verified client",
 	ArgsUsage: "<message sender> <client address> <allowance to remove> <verifier 1 address> <verifier 1 signature> <verifier 2 address> <verifier 2 signature>",
 	Action: func(cctx *cli.Context) error {
-		if cctx.Args().Len() != 7 {
+		if cctx.NArg() != 7 {
 			return fmt.Errorf("must specify seven arguments: sender, client, allowance to remove, verifier 1 address, verifier 1 signature, verifier 2 address, verifier 2 signature")
 		}