refactor(commands): move /switch channel to /check channel

/switch channel only validates availability, not actually switching.
Rename to /check channel to match actual behavior. /switch channel
now shows a redirect message pointing users to the new command.

Addresses review feedback from yinwm on PR #959.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pkg/commands/builtin.go

@@ -11,5 +11,6 @@ func BuiltinDefinitions() []Definition {
 		showCommand(),
 		listCommand(),
 		switchCommand(),
+		checkCommand(),
 	}
 }

pkg/commands/cmd_check.go

@@ -0,0 +1,33 @@
+package commands
+
+import (
+	"context"
+	"fmt"
+)
+
+func checkCommand() Definition {
+	return Definition{
+		Name:        "check",
+		Description: "Check channel availability",
+		SubCommands: []SubCommand{
+			{
+				Name:        "channel",
+				Description: "Check if a channel is available",
+				ArgsUsage:   "<name>",
+				Handler: func(_ context.Context, req Request, rt *Runtime) error {
+					if rt == nil || rt.SwitchChannel == nil {
+						return req.Reply(unavailableMsg)
+					}
+					value := nthToken(req.Text, 2)
+					if value == "" {
+						return req.Reply("Usage: /check channel <name>")
+					}
+					if err := rt.SwitchChannel(value); err != nil {
+						return req.Reply(err.Error())
+					}
+					return req.Reply(fmt.Sprintf("Channel '%s' is available and enabled", value))
+				},
+			},
+		},
+	}
+}

pkg/commands/cmd_switch.go

@@ -8,7 +8,7 @@ import (
 func switchCommand() Definition {
 	return Definition{
 		Name:        "switch",
-		Description: "Switch model or channel",
+		Description: "Switch model",
 		SubCommands: []SubCommand{
 			{
 				Name:        "model",
@@ -32,20 +32,9 @@ func switchCommand() Definition {
 			},
 			{
 				Name:        "channel",
-				Description: "Switch to a different channel",
-				ArgsUsage:   "to <name>",
-				Handler: func(_ context.Context, req Request, rt *Runtime) error {
-					if rt == nil || rt.SwitchChannel == nil {
-						return req.Reply(unavailableMsg)
-					}
-					value := nthToken(req.Text, 3)
-					if nthToken(req.Text, 2) != "to" || value == "" {
-						return req.Reply("Usage: /switch channel to <name>")
-					}
-					if err := rt.SwitchChannel(value); err != nil {
-						return req.Reply(err.Error())
-					}
-					return req.Reply(fmt.Sprintf("Channel '%s' is available and enabled", value))
+				Description: "Moved to /check channel",
+				Handler: func(_ context.Context, req Request, _ *Runtime) error {
+					return req.Reply("This command has moved. Please use: /check channel <name>")
 				},
 			},
 		},

pkg/commands/cmd_switch_test.go

@@ -122,7 +122,27 @@ func TestSwitchModel_NilDep(t *testing.T) {
 	}
 }
 
-func TestSwitchChannel_Success(t *testing.T) {
+func TestSwitchChannel_Redirect(t *testing.T) {
+	ex := NewExecutor(NewRegistry(BuiltinDefinitions()), &Runtime{})
+
+	var reply string
+	res := ex.Execute(context.Background(), Request{
+		Text: "/switch channel to telegram",
+		Reply: func(text string) error {
+			reply = text
+			return nil
+		},
+	})
+	if res.Outcome != OutcomeHandled {
+		t.Fatalf("outcome=%v, want=%v", res.Outcome, OutcomeHandled)
+	}
+	want := "This command has moved. Please use: /check channel <name>"
+	if reply != want {
+		t.Fatalf("reply=%q, want=%q", reply, want)
+	}
+}
+
+func TestCheckChannel_Success(t *testing.T) {
 	rt := &Runtime{
 		SwitchChannel: func(value string) error {
 			return nil
@@ -132,7 +152,7 @@ func TestSwitchChannel_Success(t *testing.T) {
 
 	var reply string
 	res := ex.Execute(context.Background(), Request{
-		Text: "/switch channel to telegram",
+		Text: "/check channel telegram",
 		Reply: func(text string) error {
 			reply = text
 			return nil
@@ -147,7 +167,7 @@ func TestSwitchChannel_Success(t *testing.T) {
 	}
 }
 
-func TestSwitchChannel_Error(t *testing.T) {
+func TestCheckChannel_Error(t *testing.T) {
 	rt := &Runtime{
 		SwitchChannel: func(value string) error {
 			return fmt.Errorf("channel '%s' not found", value)
@@ -157,7 +177,7 @@ func TestSwitchChannel_Error(t *testing.T) {
 
 	var reply string
 	res := ex.Execute(context.Background(), Request{
-		Text: "/switch channel to unknown",
+		Text: "/check channel unknown",
 		Reply: func(text string) error {
 			reply = text
 			return nil
@@ -171,12 +191,12 @@ func TestSwitchChannel_Error(t *testing.T) {
 	}
 }
 
-func TestSwitchChannel_NilDep(t *testing.T) {
+func TestCheckChannel_NilDep(t *testing.T) {
 	ex := NewExecutor(NewRegistry(BuiltinDefinitions()), &Runtime{})
 
 	var reply string
 	res := ex.Execute(context.Background(), Request{
-		Text: "/switch channel to telegram",
+		Text: "/check channel telegram",
 		Reply: func(text string) error {
 			reply = text
 			return nil
@@ -190,6 +210,30 @@ func TestSwitchChannel_NilDep(t *testing.T) {
 	}
 }
 
+func TestCheckChannel_MissingValue(t *testing.T) {
+	rt := &Runtime{
+		SwitchChannel: func(value string) error {
+			return nil
+		},
+	}
+	ex := NewExecutor(NewRegistry(BuiltinDefinitions()), rt)
+
+	var reply string
+	res := ex.Execute(context.Background(), Request{
+		Text: "/check channel",
+		Reply: func(text string) error {
+			reply = text
+			return nil
+		},
+	})
+	if res.Outcome != OutcomeHandled {
+		t.Fatalf("outcome=%v, want=%v", res.Outcome, OutcomeHandled)
+	}
+	if reply != "Usage: /check channel <name>" {
+		t.Fatalf("reply=%q, want usage message", reply)
+	}
+}
+
 func TestSwitch_BangPrefix(t *testing.T) {
 	rt := &Runtime{
 		SwitchModel: func(value string) (string, error) {