Update agent-task create command argument handling

Changed argument parsing to accept a maximum of one argument and assign it directly to ProblemStatement. Added error handling for missing problem statement and removed unused strings import.

pkg/cmd/agent-task/create/create.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"strings"
 	"time"
 
 	"github.com/cenkalti/backoff/v4"
@@ -35,9 +34,15 @@ func NewCmdCreate(f *cmdutil.Factory, runF func(*CreateOptions) error) *cobra.Co
 	cmd := &cobra.Command{
 		Use:   "create <problem statement>",
 		Short: "Create an agent task (preview)",
-		Args:  cobra.MinimumNArgs(1),
+		Args:  cobra.MaximumNArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			opts.ProblemStatement = strings.Join(args, " ")
+			// TODO: We'll support prompting for the problem statement if not provided
+			// and from file flags, later.
+			if len(args) == 0 {
+				return cmdutil.FlagErrorf("a problem statement is required")
+			}
+
+			opts.ProblemStatement = args[0]
 			// Support -R/--repo override
 			if f != nil {
 				opts.BaseRepo = f.BaseRepo