.sfs Format

Sessions are stored as .sfs directories containing:

• manifest.json — identity, provenance, model info, stats
• messages.jsonl — conversation history with content blocks
• workspace.json — git state, files, environment
• tools.json — tool definitions and shell context

All file paths within are relative to workspace root. Sessions are append-only — conflict resolution appends both sides rather than merging.

manifest.json

{
  "sfs_version": "0.1.0",
  "session_id": "ses_a1b2c3d4e5f6a1b2",
  "title": "Debug auth middleware",
  "tags": ["auth", "jwt"],
  "created_at": "2026-03-20T14:30:00Z",
  "updated_at": "2026-03-20T16:45:00Z",
  "source": {
    "tool": "claude-code",
    "tool_version": "2.1.59",
    "original_session_id": "abc123-def456"
  },
  "model": {
    "provider": "anthropic",
    "model_id": "claude-opus-4-6"
  },
  "stats": {
    "message_count": 47,
    "turn_count": 12,
    "tool_use_count": 28,
    "total_input_tokens": 34200,
    "total_output_tokens": 12800
  }
}

messages.jsonl

Each line is a JSON object with role, content, and optional metadata:

{"role": "user", "content": [{"type": "text", "text": "Fix the auth bug"}]}
{"role": "assistant", "content": [{"type": "text", "text": "I'll read the middleware."}]}
{"role": "assistant", "content": [{"type": "tool_use", "id": "t1", "name": "Read", "input": {"file_path": "src/auth.py"}}]}
{"role": "tool", "content": [{"type": "tool_result", "tool_use_id": "t1", "content": "import jwt\n..."}]}

Content block types: text, tool_use, tool_result, thinking, image.

workspace.json

{
  "root_path": "/Users/dev/project",
  "git": {
    "remote_url": "https://github.com/org/repo.git",
    "branch": "feature/auth-fix",
    "commit_sha": "a1b2c3d4e5f6"
  }
}