chenhg5/cc-connect · error

tmux: send-keys: %w

Error message

tmux: send-keys: %w

What it means

Send injects the prompt into the tmux pane via sendKeys(s.target, prompt). If the underlying tmux command fails (non-zero exit), Send cancels the just-started polling goroutine and returns 'tmux: send-keys: %w'. This means the prompt never reached the terminal.

Source

Thrown at agent/tmux/session.go:108

	if s.pollCancel != nil {
		s.pollCancel()
		s.pollCancel = nil
	}

	// Snapshot the full scrollback (history + visible pane) before sending.
	// extractResponse diffs against this to find exactly what the agent added,
	// regardless of whether the TUI rewrites lines in-place or scrolls them.
	baseline, _ := captureScrollback(s.target)
	visibleBase, _ := capturePane(s.target) // for poll stability comparison
	s.baselineCapture = baseline

	pollCtx, pollCancel := context.WithCancel(s.ctx)
	s.pollCancel = pollCancel
	s.mu.Unlock()

	if err := sendKeys(s.target, prompt); err != nil {
		pollCancel()
		return fmt.Errorf("tmux: send-keys: %w", err)
	}

	go s.poll(pollCtx, visibleBase)
	return nil
}

func (s *tmuxSession) poll(ctx context.Context, baseline string) {
	ticker := time.NewTicker(s.pollInt)
	defer ticker.Stop()

	prev := baseline
	stable := 0

	for {
		select {
		case <-ctx.Done():
			return
		case <-ticker.C:

View on GitHub (pinned to 4000b2338a)

Solutions

1. Run `tmux list-sessions` / `tmux display-message -t <target>` to confirm the target exists
2. Recreate the tmux session/pane (or correct the target string in config) and send again
3. Verify the tmux binary is on PATH for the user running cc-connect (`cc-connect doctor` if available)
4. If sessions are transient, use tmux resurrect/continue or have the agent create its own session rather than attaching to a user-managed one

Example fix

// config.toml: wrong target
# target = "agent:0.1"   # pane does not exist
// after
# target = "agent:0.0"

// verify target before sending
cmd := exec.Command("tmux", "has-session", "-t", targetSession)
if err := cmd.Run(); err != nil {
    return fmt.Errorf("tmux target %q missing", targetSession)
}

// Go
if err := sess.Send(prompt, id, nil, files); err != nil {
    if strings.Contains(err.Error(), "send-keys") {
        slog.Error("tmux pane gone; recreate session", "err", err)
        // fall back to restarting the tmux session
    }
}

When it happens

Trigger: The tmux target (session:window.pane) no longer exists — tmux was restarted, the session was killed, or the pane closed — so `tmux send-keys -t <target>` exits with an error.

Common situations: User closed the tmux pane or ran `tmux kill-session` while chatting; server rebooted and tmux wasn't restored; the configured tmux target string has a typo so the target never existed; tmux binary missing from PATH in a daemonized environment.

Understand the failure class

Background: "git command failed": what it means when a tool shells out to git and git exits non-zero — this error's family across 21 libraries.

Related errors

• %w: %s
• antigravitySession: stdout pipe: %w
• antigravitySession: start: %w
• %s
• read stdout: %w

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/f9282d6aff843d15. Report an issue: GitHub.