Improve user facing error massage when the stack is not found

internal/cmd/stack/local_preview.go

@@ -61,7 +61,7 @@ func localPreview() cli.ActionFunc {
 		}
 
 		if err := authenticated.Client.Mutate(ctx, &uploadMutation, uploadVariables); err != nil {
-			return err
+			return fmt.Errorf("failed to upload local workspace: %w", err)
 		}
 
 		fp := filepath.Join(os.TempDir(), "spacectl", "local-workspace", fmt.Sprintf("%s.tar.gz", uploadMutation.UploadLocalWorkspace.ID))

internal/cmd/stack/stack_selector.go

@@ -7,6 +7,8 @@ import (
 
 	"github.com/manifoldco/promptui"
 	"github.com/pkg/errors"
+	"github.com/shurcooL/graphql"
+	"github.com/spacelift-io/spacectl/internal/cmd/authenticated"
 	"github.com/urfave/cli/v2"
 )
 
@@ -18,7 +20,15 @@ var errNoStackFound = errors.New("no stack found")
 // 2. Check the current directory to determine repository and subdirectory and search for a stack.
 func getStackID(cliCtx *cli.Context) (string, error) {
 	if cliCtx.IsSet(flagStackID.Name) {
-		return cliCtx.String(flagStackID.Name), nil
+		stackId := cliCtx.String(flagStackID.Name)
+		exists, err := stackExists(cliCtx.Context, stackId)
+		if err != nil {
+			return "", fmt.Errorf("failed to check if stack exists: %w", err)
+		}
+		if !exists {
+			return "", fmt.Errorf("Stack with id %q could not be found. Please check that the stack exists and that you have access to it. To list available stacks run: spacectl stack list", stackId)
+		}
+		return stackId, nil
 	}
 
 	subdir, err := getGitRepositorySubdir()
@@ -47,6 +57,28 @@ func getStackID(cliCtx *cli.Context) (string, error) {
 	return got, nil
 }
 
+func stackExists(ctx context.Context, stackId string) (bool, error) {
+	var query struct {
+		Stack struct {
+			ID string `graphql:"id"`
+		} `graphql:"stack(id: $id)"`
+	}
+
+	variables := map[string]interface{}{
+		"id": graphql.ID(stackId),
+	}
+
+	err := authenticated.Client.Query(ctx, &query, variables)
+	if err != nil {
+		return false, fmt.Errorf("failed to query GraphQL API when checking if a stack exists: %w", err)
+	}
+
+	if query.Stack.ID == "" {
+		return false, nil
+	}
+	return true, nil
+}
+
 func findAndSelectStack(ctx context.Context, p *stackSearchParams, forcePrompt bool) (string, error) {
 	stacks, err := searchStacks(ctx, p)
 	if err != nil {