byre/internal/agents/hands.go

package agents

import (
	"os"
	"os/exec"
	"path/filepath"

	"g.fc.run/ai/byre/internal/mcp"
)

const screenshotGuidance = "\n- When a turn changes something you can see, you can show it in your final message: save screenshots with the Playwright tools (pages you serve on this task's ports) or hands' capture with save (apps on this Mac), and embed each as a Markdown image, ![what it shows](<path>), with the path the tool returned. They go to the task's media folder, outside the worktree, so they are never committed, and are deleted when the task closes. Leave out a screenshot that adds nothing to the text."

func MediaDir(worktreePath string) string {
	return worktreePath + "-media"
}

func (m *Manager) handsDir(sessionID string) string {
	return filepath.Join(m.handsRoot, sessionID)
}

// replayd keys ScreenCaptureKit clients by executable path, so two hands
// processes run from one path keep cancelling each other's connection.
func (m *Manager) handsMCP(sessionID, mediaDir string) (mcp.Stdio, error) {
	src, err := exec.LookPath("byre-hands")
	if err != nil {
		return mcp.Stdio{}, err
	}
	data, err := os.ReadFile(src)
	if err != nil {
		return mcp.Stdio{}, err
	}
	dir := m.handsDir(sessionID)
	err = os.RemoveAll(dir)
	if err != nil {
		return mcp.Stdio{}, err
	}
	err = os.MkdirAll(dir, 0o755)
	if err != nil {
		return mcp.Stdio{}, err
	}
	bin := filepath.Join(dir, "byre-hands")
	err = os.WriteFile(bin, data, 0o755)
	if err != nil {
		return mcp.Stdio{}, err
	}
	return mcp.Stdio{Name: "hands", Command: bin, Args: []string{"--media-dir", mediaDir}}, nil
}