diff --git a/nano-claude-code/config.py b/nano-claude-code/config.py
new file mode 100644
index 0000000..9008729
--- /dev/null
+++ b/nano-claude-code/config.py
@@ -0,0 +1,69 @@
+"""Configuration management for nano claude (multi-provider)."""
+import os
+import json
+from pathlib import Path
+
+CONFIG_DIR   = Path.home() / ".nano_claude"
+CONFIG_FILE  = CONFIG_DIR  / "config.json"
+HISTORY_FILE = CONFIG_DIR  / "input_history.txt"
+SESSIONS_DIR = CONFIG_DIR  / "sessions"
+
+DEFAULTS = {
+    "model":            "claude-opus-4-6",
+    "max_tokens":       8192,
+    "permission_mode":  "auto",   # auto | accept-all | manual
+    "verbose":          False,
+    "thinking":         False,
+    "thinking_budget":  10000,
+    "custom_base_url":  "",       # for "custom" provider
+    # Per-provider API keys (optional; env vars take priority)
+    # "anthropic_api_key": "sk-ant-..."
+    # "openai_api_key":    "sk-..."
+    # "gemini_api_key":    "..."
+    # "kimi_api_key":      "..."
+    # "qwen_api_key":      "..."
+    # "zhipu_api_key":     "..."
+    # "deepseek_api_key":  "..."
+}
+
+
+def load_config() -> dict:
+    CONFIG_DIR.mkdir(exist_ok=True)
+    SESSIONS_DIR.mkdir(exist_ok=True)
+    cfg = dict(DEFAULTS)
+    if CONFIG_FILE.exists():
+        try:
+            cfg.update(json.loads(CONFIG_FILE.read_text()))
+        except Exception:
+            pass
+    # Backward-compat: legacy single api_key → anthropic_api_key
+    if cfg.get("api_key") and not cfg.get("anthropic_api_key"):
+        cfg["anthropic_api_key"] = cfg.pop("api_key")
+    # Also accept ANTHROPIC_API_KEY env for backward-compat
+    if not cfg.get("anthropic_api_key"):
+        cfg["anthropic_api_key"] = os.environ.get("ANTHROPIC_API_KEY", "")
+    return cfg
+
+
+def save_config(cfg: dict):
+    CONFIG_DIR.mkdir(exist_ok=True)
+    data = dict(cfg)
+    CONFIG_FILE.write_text(json.dumps(data, indent=2))
+
+
+def current_provider(cfg: dict) -> str:
+    from providers import detect_provider
+    return detect_provider(cfg.get("model", "claude-opus-4-6"))
+
+
+def has_api_key(cfg: dict) -> bool:
+    """Check whether the active provider has an API key configured."""
+    from providers import get_api_key
+    pname = current_provider(cfg)
+    key = get_api_key(pname, cfg)
+    return bool(key)
+
+
+def calc_cost(model: str, in_tokens: int, out_tokens: int) -> float:
+    from providers import calc_cost as _cc
+    return _cc(model, in_tokens, out_tokens)
diff --git a/nano-claude-code/context.py b/nano-claude-code/context.py
new file mode 100644
index 0000000..6b12e20
--- /dev/null
+++ b/nano-claude-code/context.py
@@ -0,0 +1,100 @@
+"""System context: CLAUDE.md, git info, cwd injection."""
+import os
+import subprocess
+from pathlib import Path
+from datetime import datetime
+
+SYSTEM_PROMPT_TEMPLATE = """\
+You are Nano Claude Code, Created by SAIL Lab (Safe AI and Robot Learning Lab), an AI coding assistant running in the terminal.
+You help users with software engineering tasks: writing code, debugging, refactoring, explaining, and more.
+
+# Available Tools
+- **Read**: Read file contents with line numbers
+- **Write**: Create or overwrite files
+- **Edit**: Replace text in a file (exact string replacement)
+- **Bash**: Execute shell commands
+- **Glob**: Find files by pattern (e.g. **/*.py)
+- **Grep**: Search file contents with regex
+- **WebFetch**: Fetch and extract content from a URL
+- **WebSearch**: Search the web via DuckDuckGo
+
+# Guidelines
+- Be concise and direct. Lead with the answer.
+- Prefer editing existing files over creating new ones.
+- Do not add unnecessary comments, docstrings, or error handling.
+- When reading files before editing, use line numbers to be precise.
+- Always use absolute paths for file operations.
+- For multi-step tasks, work through them systematically.
+- If a task is unclear, ask for clarification before proceeding.
+
+# Environment
+- Current date: {date}
+- Working directory: {cwd}
+- Platform: {platform}
+{git_info}{claude_md}"""
+
+
+def get_git_info() -> str:
+    """Return git branch/status summary if in a git repo."""
+    try:
+        branch = subprocess.check_output(
+            ["git", "rev-parse", "--abbrev-ref", "HEAD"],
+            stderr=subprocess.DEVNULL, text=True).strip()
+        status = subprocess.check_output(
+            ["git", "status", "--short"],
+            stderr=subprocess.DEVNULL, text=True).strip()
+        log = subprocess.check_output(
+            ["git", "log", "--oneline", "-5"],
+            stderr=subprocess.DEVNULL, text=True).strip()
+        parts = [f"- Git branch: {branch}"]
+        if status:
+            lines = status.split('\n')[:10]
+            parts.append("- Git status:\n" + "\n".join(f"  {l}" for l in lines))
+        if log:
+            parts.append("- Recent commits:\n" + "\n".join(f"  {l}" for l in log.split('\n')))
+        return "\n".join(parts) + "\n"
+    except Exception:
+        return ""
+
+
+def get_claude_md() -> str:
+    """Load CLAUDE.md from cwd or parents, and ~/.claude/CLAUDE.md."""
+    content_parts = []
+
+    # Global CLAUDE.md
+    global_md = Path.home() / ".claude" / "CLAUDE.md"
+    if global_md.exists():
+        try:
+            content_parts.append(f"[Global CLAUDE.md]\n{global_md.read_text()}")
+        except Exception:
+            pass
+
+    # Project CLAUDE.md (walk up from cwd)
+    p = Path.cwd()
+    for _ in range(10):
+        candidate = p / "CLAUDE.md"
+        if candidate.exists():
+            try:
+                content_parts.append(f"[Project CLAUDE.md: {candidate}]\n{candidate.read_text()}")
+            except Exception:
+                pass
+            break
+        parent = p.parent
+        if parent == p:
+            break
+        p = parent
+
+    if not content_parts:
+        return ""
+    return "\n# Memory / CLAUDE.md\n" + "\n\n".join(content_parts) + "\n"
+
+
+def build_system_prompt() -> str:
+    import platform
+    return SYSTEM_PROMPT_TEMPLATE.format(
+        date=datetime.now().strftime("%Y-%m-%d %A"),
+        cwd=str(Path.cwd()),
+        platform=platform.system(),
+        git_info=get_git_info(),
+        claude_md=get_claude_md(),
+    )
diff --git a/nano-claude-code/demo.py b/nano-claude-code/demo.py
new file mode 100644
index 0000000..28b0ca4
--- /dev/null
+++ b/nano-claude-code/demo.py
@@ -0,0 +1,91 @@
+#!/usr/bin/env python3
+"""
+Demo script for nano claude code.
+Requires ANTHROPIC_API_KEY environment variable.
+
+Run:
+  ANTHROPIC_API_KEY=sk-... python demo.py
+"""
+import os
+import sys
+
+# Add parent path for imports
+sys.path.insert(0, os.path.dirname(__file__))
+
+from config import load_config
+from context import build_system_prompt
+from agent import AgentState, run, TextChunk, ThinkingChunk, ToolStart, ToolEnd, TurnDone, PermissionRequest
+
+def demo():
+    config = load_config()
+    if not config["api_key"]:
+        print("Error: Set ANTHROPIC_API_KEY environment variable")
+        sys.exit(1)
+
+    config["permission_mode"] = "accept-all"  # Demo: auto-approve everything
+    config["verbose"] = True
+    state = AgentState()
+    system_prompt = build_system_prompt()
+
+    print("=" * 60)
+    print("DEMO 1: Simple question (no tools)")
+    print("=" * 60)
+    _run_demo(state, config, system_prompt,
+              "What is the time complexity of quicksort? Answer in 2 sentences.")
+
+    print("\n" + "=" * 60)
+    print("DEMO 2: File system exploration (uses Glob + Read tools)")
+    print("=" * 60)
+    state2 = AgentState()
+    _run_demo(state2, config, system_prompt,
+              "List all Python files in the current directory and show me the first 5 lines of nano_claude.py")
+
+    print("\n" + "=" * 60)
+    print("DEMO 3: Code writing (uses Write + Bash tools)")
+    print("=" * 60)
+    state3 = AgentState()
+    _run_demo(state3, config, system_prompt,
+              "Write a Python function to fibonacci(n) in /tmp/fib.py, then run it to test fib(10)")
+
+    print("\n" + "=" * 60)
+    print("DEMO 4: Multi-turn conversation")
+    print("=" * 60)
+    state4 = AgentState()
+    _run_demo(state4, config, system_prompt,
+              "What are the tools available to you?")
+    _run_demo(state4, config, system_prompt,
+              "Which of those tools would you use to find all TODO comments in a codebase?")
+
+    print("\n" + "=" * 60)
+    print("DEMO 5: Web search")
+    print("=" * 60)
+    state5 = AgentState()
+    _run_demo(state5, config, system_prompt,
+              "Search the web for 'Python 3.13 new features' and give me a brief summary")
+
+
+def _run_demo(state: AgentState, config: dict, system_prompt: str, prompt: str):
+    print(f"\n[USER]: {prompt}\n")
+    print("[CLAUDE]: ", end="", flush=True)
+
+    for event in run(prompt, state, config, system_prompt):
+        if isinstance(event, TextChunk):
+            print(event.text, end="", flush=True)
+        elif isinstance(event, ThinkingChunk):
+            if config.get("verbose"):
+                print(f"\033[2m[thinking: {event.text[:100]}]\033[0m", end="", flush=True)
+        elif isinstance(event, ToolStart):
+            print(f"\n\033[36m  ⚙ {event.name}({list(event.inputs.values())[0] if event.inputs else ''})\033[0m", flush=True)
+        elif isinstance(event, PermissionRequest):
+            event.granted = True  # Auto-approve in demo
+        elif isinstance(event, ToolEnd):
+            result_preview = event.result[:100].replace('\n', '↵')
+            print(f"\033[32m  ✓ → {result_preview}\033[0m", flush=True)
+        elif isinstance(event, TurnDone):
+            print(f"\n\033[2m  [+{event.input_tokens} in / +{event.output_tokens} out]\033[0m", flush=True)
+
+    print()
+
+
+if __name__ == "__main__":
+    demo()
diff --git a/nano-claude-code/make_demo.py b/nano-claude-code/make_demo.py
new file mode 100644
index 0000000..d92eb96
--- /dev/null
+++ b/nano-claude-code/make_demo.py
@@ -0,0 +1,417 @@
+#!/usr/bin/env python3
+"""
+Generate animated GIF demo of nano claude code using PIL.
+Simulates a realistic terminal session with tool calls.
+"""
+from PIL import Image, ImageDraw, ImageFont
+import os, textwrap
+
+# ── Catppuccin Mocha palette ─────────────────────────────────────────────
+BG      = (30,  30,  46)   # base
+SURFACE = (49,  50,  68)   # surface0
+TEXT    = (205, 214, 244)  # text
+SUBTEXT = (108, 112, 134)  # overlay0 (dim)
+CYAN    = (137, 220, 235)  # sky
+GREEN   = (166, 227, 161)  # green
+YELLOW  = (249, 226, 175)  # yellow
+RED     = (243, 139, 168)  # red
+MAUVE   = (203, 166, 247)  # mauve (user prompt)
+BLUE    = (137, 180, 250)  # blue
+PEACH   = (250, 179, 135)  # peach
+
+W, H = 960, 720
+FONT_PATH  = "/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf"
+FONT_BOLD  = "/usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf"
+FONT_SIZE  = 14
+LINE_H     = 20
+PAD_X      = 18
+PAD_Y      = 16
+
+
+def make_font(size=FONT_SIZE, bold=False):
+    path = FONT_BOLD if bold else FONT_PATH
+    try:
+        return ImageFont.truetype(path, size)
+    except:
+        return ImageFont.load_default()
+
+
+FONT      = make_font()
+FONT_B    = make_font(bold=True)
+FONT_SM   = make_font(FONT_SIZE - 1)
+
+
+# ── Segment: (text, color, bold?) ────────────────────────────────────────
+Seg = tuple   # (str, rgb_tuple, bool)
+
+
+def seg(t, c=TEXT, b=False): return (t, c, b)
+def segs(*args): return list(args)
+
+
+def render_line(draw, y, segments, x_start=PAD_X):
+    x = x_start
+    for text, color, bold in segments:
+        font = FONT_B if bold else FONT
+        draw.text((x, y), text, font=font, fill=color)
+        x += font.getlength(text)
+    return y + LINE_H
+
+
+def blank_frame():
+    img = Image.new("RGB", (W, H), BG)
+    return img
+
+
+def draw_frame(lines_segments):
+    """
+    lines_segments: list of either
+      - list[Seg]  → rendered as a line
+      - None       → blank line
+    Returns PIL Image.
+    """
+    img = blank_frame()
+    d   = ImageDraw.Draw(img)
+    y = PAD_Y
+    for item in lines_segments:
+        if item is None:
+            y += LINE_H
+        elif isinstance(item, list):
+            y = render_line(d, y, item)
+        else:
+            y = render_line(d, y, [item])
+    return img
+
+
+# ── Pre-defined screen content blocks ───────────────────────────────────
+
+BANNER = [
+    [seg("╭─ Nano Claude Code ──────────────────────────────────────────╮", SUBTEXT)],
+    [seg("│  ", SUBTEXT), seg("Model: ", SUBTEXT), seg("claude-opus-4-6", CYAN, True)],
+    [seg("│  ", SUBTEXT), seg("Permissions: ", SUBTEXT), seg("auto", YELLOW)],
+    [seg("│  Type /help for commands, Ctrl+C to cancel                  │", SUBTEXT)],
+    [seg("╰────────────────────────────────────────────────────────────╯", SUBTEXT)],
+    None,
+]
+
+def prompt_line(text="", cursor=False):
+    cur = "█" if cursor else ""
+    return [
+        seg("[nano_claude_code] ", SUBTEXT),
+        seg("❯ ", CYAN, True),
+        seg(text + cur, TEXT),
+    ]
+
+def claude_header():
+    return [
+        seg("╭─ Claude ", SUBTEXT),
+        seg("●", GREEN),
+        seg(" ─────────────────────────────────────────────", SUBTEXT),
+    ]
+
+def claude_sep():
+    return [seg("╰──────────────────────────────────────────────────────────", SUBTEXT)]
+
+def tool_line(icon, name, arg, color=CYAN):
+    return [
+        seg(f"  {icon}  ", SUBTEXT),
+        seg(name, color),
+        seg("(", SUBTEXT),
+        seg(arg, TEXT),
+        seg(")", SUBTEXT),
+    ]
+
+def tool_ok(msg):
+    return [seg(f"  ✓ ", GREEN), seg(msg, SUBTEXT)]
+
+def tool_err(msg):
+    return [seg(f"  ✗ ", RED), seg(msg, SUBTEXT)]
+
+def text_line(t, indent=2):
+    return [seg(" " * indent + t, TEXT)]
+
+def dim_line(t, indent=4):
+    return [seg(" " * indent + t, SUBTEXT)]
+
+
+# ── Scene builder ─────────────────────────────────────────────────────────
+
+def build_scenes():
+    """Return list of (frame_content, duration_ms)."""
+    scenes = []
+    def add(lines, ms=120):
+        scenes.append((lines, ms))
+
+    # ── Scene 0: Empty terminal with banner ──────────────────────────────
+    add(BANNER + [prompt_line(cursor=True)], 800)
+
+    # ── Scene 1: User types query 1 ──────────────────────────────────────
+    msg1 = "List Python files in this project and show me their line counts"
+    for i in range(0, len(msg1) + 1, 3):
+        add(BANNER + [prompt_line(msg1[:i], cursor=(i < len(msg1)))], 60)
+    add(BANNER + [prompt_line(msg1, cursor=False)], 400)
+
+    # ── Scene 2: Claude header appears ──────────────────────────────────
+    pre = BANNER + [prompt_line(msg1)]
+    add(pre + [None, claude_header(), [seg("│ ", SUBTEXT)]], 300)
+
+    # ── Scene 3: Tool call - Glob ────────────────────────────────────────
+    base = pre + [None, claude_header()]
+    add(base + [
+        tool_line("⚙", "Glob", "**/*.py"),
+    ], 500)
+    add(base + [
+        tool_line("⚙", "Glob", "**/*.py"),
+        tool_ok("5 files matched"),
+    ], 600)
+
+    # ── Scene 4: Tool call - Bash (wc -l) ────────────────────────────────
+    add(base + [
+        tool_line("⚙", "Glob", "**/*.py"),
+        tool_ok("5 files matched"),
+        None,
+        tool_line("⚙", "Bash", "wc -l *.py | sort -n"),
+    ], 500)
+    add(base + [
+        tool_line("⚙", "Glob", "**/*.py"),
+        tool_ok("5 files matched"),
+        None,
+        tool_line("⚙", "Bash", "wc -l *.py | sort -n"),
+        tool_ok("→ 6 lines (120 chars)"),
+    ], 700)
+
+    # ── Scene 5: Claude streams response ────────────────────────────────
+    response_lines = [
+        "Here are the Python files in this project with their line counts:",
+        "",
+        "  76  config.py      — Configuration management and cost calculation",
+        " 100  context.py     — System prompt builder, CLAUDE.md + git injection",
+        " 173  agent.py       — Core agent loop with streaming API calls",
+        " 359  tools.py       — 8 built-in tools (Read/Write/Edit/Bash/Glob/Grep/Web)",
+        " 553  nano_claude.py — REPL entry point, slash commands, rich rendering",
+        "────────────────────────────────────────────────────",
+        "1261  total",
+        "",
+        "The largest file is `nano_claude.py` containing the interactive REPL,",
+        "14 slash commands, permission handling, and markdown rendering.",
+    ]
+    tool_section = [
+        tool_line("⚙", "Glob", "**/*.py"),
+        tool_ok("5 files matched"),
+        None,
+        tool_line("⚙", "Bash", "wc -l *.py | sort -n"),
+        tool_ok("→ 6 lines (120 chars)"),
+        None,
+        [seg("│ ", SUBTEXT)],
+    ]
+    streamed = []
+    for i, rline in enumerate(response_lines):
+        streamed.append(text_line(rline, 2))
+        content = base + tool_section + streamed
+        add(content, 80 if rline else 30)
+
+    add(base + tool_section + [text_line(l, 2) for l in response_lines] + [claude_sep()], 1200)
+
+    # ── Scene 6: New prompt appears ──────────────────────────────────────
+    full1 = (pre + [None, claude_header()] +
+             tool_section +
+             [text_line(l, 2) for l in response_lines] +
+             [claude_sep(), None])
+    add(full1 + [prompt_line(cursor=True)], 800)
+
+    # ── Scene 7: User types query 2 ──────────────────────────────────────
+    msg2 = "Write a hello_world.py that prints 'Hello from Nano Claude!'"
+    for i in range(0, len(msg2) + 1, 4):
+        add(full1 + [prompt_line(msg2[:i], cursor=(i < len(msg2)))], 55)
+    add(full1 + [prompt_line(msg2)], 400)
+
+    # ── Scene 8: Write tool call ─────────────────────────────────────────
+    base2 = full1 + [prompt_line(msg2), None, claude_header()]
+    add(base2 + [
+        tool_line("⚙", "Write", "/tmp/hello_world.py", MAUVE),
+    ], 600)
+    add(base2 + [
+        tool_line("⚙", "Write", "/tmp/hello_world.py", MAUVE),
+        tool_ok("Wrote 3 lines to /tmp/hello_world.py"),
+        None,
+        tool_line("⚙", "Bash", "python3 /tmp/hello_world.py"),
+    ], 500)
+    add(base2 + [
+        tool_line("⚙", "Write", "/tmp/hello_world.py", MAUVE),
+        tool_ok("Wrote 3 lines to /tmp/hello_world.py"),
+        None,
+        tool_line("⚙", "Bash", "python3 /tmp/hello_world.py"),
+        tool_ok("→ Hello from Nano Claude!"),
+    ], 800)
+
+    # ── Scene 9: Final response ──────────────────────────────────────────
+    resp2 = [
+        "Done! Created `/tmp/hello_world.py` and ran it successfully.",
+        "",
+        "  print('Hello from Nano Claude!')",
+        "",
+        "Output: Hello from Nano Claude!",
+    ]
+    tool2 = [
+        tool_line("⚙", "Write", "/tmp/hello_world.py", MAUVE),
+        tool_ok("Wrote 3 lines to /tmp/hello_world.py"),
+        None,
+        tool_line("⚙", "Bash", "python3 /tmp/hello_world.py"),
+        tool_ok("→ Hello from Nano Claude!"),
+        None,
+        [seg("│ ", SUBTEXT)],
+    ]
+    streamed2 = []
+    for rline in resp2:
+        streamed2.append(text_line(rline, 2))
+        add(base2 + tool2 + streamed2, 90)
+
+    add(base2 + tool2 + [text_line(l, 2) for l in resp2] + [claude_sep()], 1500)
+
+    # ── Scene 10: Slash command demo ─────────────────────────────────────
+    final_state = (full1 + [prompt_line(msg2), None, claude_header()] +
+                   tool2 + [text_line(l, 2) for l in resp2] + [claude_sep(), None])
+    add(final_state + [prompt_line(cursor=True)], 600)
+
+    slash = "/cost"
+    for i in range(len(slash) + 1):
+        add(final_state + [prompt_line(slash[:i], cursor=(i < len(slash)))], 80)
+    add(final_state + [prompt_line(slash)], 400)
+
+    # cost output
+    cost_lines = [
+        [seg("Input tokens:  ", CYAN), seg("1,842", TEXT, True)],
+        [seg("Output tokens: ", CYAN), seg("312", TEXT, True)],
+        [seg("Est. cost:     ", CYAN), seg("$0.0318 USD", GREEN, True)],
+    ]
+    add(final_state + [prompt_line(slash), None] + cost_lines + [None, prompt_line(cursor=True)], 2000)
+
+    return scenes
+
+
+# ── Render ────────────────────────────────────────────────────────────────
+
+def _build_explicit_palette():
+    """
+    Build a 256-entry palette from our exact theme colors.
+    Returns flat list of 768 ints (R,G,B, R,G,B, ...) suitable for putpalette().
+    """
+    # All distinct colors used in the renderer
+    theme = [
+        BG, SURFACE, TEXT, SUBTEXT,
+        CYAN, GREEN, YELLOW, RED, MAUVE, BLUE, PEACH,
+        (255, 255, 255), (0, 0, 0),
+        # Extra intermediate shades that PIL might snap to
+        (50, 55, 80),   # surface variant
+        (90, 95, 120),  # dim text variant
+        (160, 166, 200),
+    ]
+    flat = []
+    for c in theme:
+        flat.extend(c)
+    # Pad to 256 entries with black
+    while len(flat) < 256 * 3:
+        flat.extend((0, 0, 0))
+    return flat
+
+
+def render_gif(output_path="demo.gif"):
+    print("Building scenes...")
+    scenes = build_scenes()
+    print(f"  {len(scenes)} scenes")
+
+    palette_data = _build_explicit_palette()
+
+    # Create a palette-mode reference image for quantize()
+    pal_ref = Image.new("P", (1, 1))
+    pal_ref.putpalette(palette_data)
+
+    print("  Rendering frames...")
+    rgb_frames = []
+    durations  = []
+    for i, (lines, ms) in enumerate(scenes):
+        img = draw_frame(lines)
+        rgb_frames.append(img)
+        durations.append(ms)
+        if i % 20 == 0:
+            print(f"  {i}/{len(scenes)}...")
+
+    # Quantize all frames to the same explicit palette (no dither → exact snap)
+    print("  Quantizing to global palette...")
+    p_frames = [f.quantize(palette=pal_ref, dither=0) for f in rgb_frames]
+
+    print(f"Saving GIF → {output_path}  ({len(p_frames)} frames)...")
+    p_frames[0].save(
+        output_path,
+        save_all=True,
+        append_images=p_frames[1:],
+        duration=durations,
+        loop=0,
+        optimize=False,
+    )
+    size_kb = os.path.getsize(output_path) // 1024
+    print(f"Done! {size_kb} KB")
+
+
+# ── Static screenshot ─────────────────────────────────────────────────────
+
+def render_screenshot(output_path="screenshot.png"):
+    """Single high-quality screenshot showing a complete session."""
+    lines = (
+        BANNER +
+        [prompt_line("List Python files and their line counts")] +
+        [None, claude_header()] +
+        [
+            tool_line("⚙", "Glob", "**/*.py"),
+            tool_ok("5 files matched"),
+            None,
+            tool_line("⚙", "Bash", "wc -l *.py | sort -n"),
+            tool_ok("→ 6 lines (120 chars)"),
+            None,
+            [seg("│ ", SUBTEXT)],
+            text_line("Here are the Python files with their line counts:", 2),
+            None,
+            text_line("  76  config.py      — Configuration management", 2),
+            text_line(" 100  context.py     — System prompt + git injection", 2),
+            text_line(" 173  agent.py       — Core agent loop", 2),
+            text_line(" 359  tools.py       — 8 built-in tools", 2),
+            text_line(" 553  nano_claude.py — REPL + slash commands", 2),
+            text_line("────────────────────────────────", 2),
+            text_line("1261  total", 2),
+            None,
+            text_line("The main entry point `nano_claude.py` contains the REPL,", 2),
+            text_line("14 slash commands, permission handling, and rich rendering.", 2),
+            claude_sep(),
+            None,
+            prompt_line("/cost"),
+            None,
+            [seg("Input tokens:  ", CYAN), seg("1,842", TEXT, True)],
+            [seg("Output tokens: ", CYAN), seg("312", TEXT, True)],
+            [seg("Est. cost:     ", CYAN), seg("$0.0318 USD", GREEN, True)],
+            None,
+            prompt_line(cursor=True),
+        ]
+    )
+    img = draw_frame(lines)
+
+    # Add subtle rounded border effect
+    d = ImageDraw.Draw(img)
+    d.rectangle([0, 0, W-1, H-1], outline=SURFACE, width=2)
+
+    img.save(output_path, format="PNG", optimize=True)
+    size_kb = os.path.getsize(output_path) // 1024
+    print(f"Screenshot saved: {output_path}  ({size_kb} KB)")
+
+
+if __name__ == "__main__":
+    import sys
+    out_dir = os.path.dirname(os.path.abspath(__file__))
+
+    gif_path = os.path.join(out_dir, "demo.gif")
+    png_path = os.path.join(out_dir, "screenshot.png")
+
+    render_screenshot(png_path)
+    render_gif(gif_path)
+    print("\nFiles created:")
+    print(f"  {png_path}")
+    print(f"  {gif_path}")
diff --git a/nano-claude-code/nano_claude.py b/nano-claude-code/nano_claude.py
new file mode 100644
index 0000000..8294b4a
--- /dev/null
+++ b/nano-claude-code/nano_claude.py
@@ -0,0 +1,576 @@
+#!/usr/bin/env python3
+"""
+Nano Claude Code — Minimal Python implementation of Claude Code.
+
+Usage:
+  python nano_claude.py [options] [prompt]
+
+Options:
+  -p, --print          Non-interactive: run prompt and exit (also --print-output)
+  -m, --model MODEL    Override model
+  --accept-all         Never ask permission (dangerous)
+  --verbose            Show thinking + token counts
+  --version            Print version and exit
+
+Slash commands in REPL:
+  /help       Show this help
+  /clear      Clear conversation
+  /model [m]  Show or set model
+  /config     Show config / set key=value
+  /save [f]   Save session to file
+  /load [f]   Load session from file
+  /history    Print conversation history
+  /context    Show context window usage
+  /cost       Show API cost this session
+  /verbose    Toggle verbose mode
+  /thinking   Toggle extended thinking
+  /permissions [mode]  Set permission mode
+  /cwd [path] Show or change working directory
+  /exit /quit Exit
+"""
+from __future__ import annotations
+
+import os
+import sys
+import json
+import readline
+import atexit
+import argparse
+import textwrap
+from pathlib import Path
+from datetime import datetime
+from typing import Optional
+
+# ── Optional rich for markdown rendering ──────────────────────────────────
+try:
+    from rich.console import Console
+    from rich.markdown import Markdown
+    from rich.syntax import Syntax
+    from rich.panel import Panel
+    from rich import print as rprint
+    _RICH = True
+    console = Console()
+except ImportError:
+    _RICH = False
+    console = None
+
+VERSION = "1.0.0"
+
+# ── ANSI helpers (used even with rich for non-markdown output) ─────────────
+C = {
+    "cyan":    "\033[36m",
+    "green":   "\033[32m",
+    "yellow":  "\033[33m",
+    "red":     "\033[31m",
+    "blue":    "\033[34m",
+    "magenta": "\033[35m",
+    "bold":    "\033[1m",
+    "dim":     "\033[2m",
+    "reset":   "\033[0m",
+}
+
+def clr(text: str, *keys: str) -> str:
+    return "".join(C[k] for k in keys) + str(text) + C["reset"]
+
+def info(msg: str):   print(clr(msg, "cyan"))
+def ok(msg: str):     print(clr(msg, "green"))
+def warn(msg: str):   print(clr(f"Warning: {msg}", "yellow"))
+def err(msg: str):    print(clr(f"Error: {msg}", "red"), file=sys.stderr)
+
+
+# ── Conversation rendering ─────────────────────────────────────────────────
+
+_accumulated_text: list[str] = []   # buffer text during streaming
+
+def stream_text(chunk: str):
+    """Called for each streamed text chunk."""
+    print(chunk, end="", flush=True)
+    _accumulated_text.append(chunk)
+
+def stream_thinking(chunk: str, verbose: bool):
+    if verbose:
+        print(clr(chunk, "dim"), end="", flush=True)
+
+def flush_response():
+    """After streaming, optionally re-render as markdown."""
+    full = "".join(_accumulated_text)
+    _accumulated_text.clear()
+    if _RICH and full.strip():
+        # Re-print with markdown rendering
+        print("\r", end="")      # go to line start to overwrite last newline
+        # only re-render if there's actual markdown (contains # * ` _ etc.)
+        if any(c in full for c in ("#", "*", "`", "_", "[")):
+            print()   # newline after streaming
+            console.print(Markdown(full))
+            return
+    print()  # ensure newline after stream
+
+def print_tool_start(name: str, inputs: dict, verbose: bool):
+    """Show tool invocation."""
+    desc = _tool_desc(name, inputs)
+    print(clr(f"\n  ⚙  {desc}", "dim", "cyan"), flush=True)
+    if verbose:
+        print(clr(f"     inputs: {json.dumps(inputs, ensure_ascii=False)[:200]}", "dim"))
+
+def print_tool_end(name: str, result: str, verbose: bool):
+    lines = result.count("\n") + 1
+    size = len(result)
+    summary = f"→ {lines} lines ({size} chars)"
+    if not result.startswith("Error") and not result.startswith("Denied"):
+        print(clr(f"  ✓ {summary}", "dim", "green"), flush=True)
+    else:
+        print(clr(f"  ✗ {result[:120]}", "dim", "red"), flush=True)
+    if verbose and not result.startswith("Denied"):
+        preview = result[:500] + ("…" if len(result) > 500 else "")
+        print(clr(f"     {preview.replace(chr(10), chr(10)+'     ')}", "dim"))
+
+def _tool_desc(name: str, inputs: dict) -> str:
+    if name == "Read":   return f"Read({inputs.get('file_path','')})"
+    if name == "Write":  return f"Write({inputs.get('file_path','')})"
+    if name == "Edit":   return f"Edit({inputs.get('file_path','')})"
+    if name == "Bash":   return f"Bash({inputs.get('command','')[:80]})"
+    if name == "Glob":   return f"Glob({inputs.get('pattern','')})"
+    if name == "Grep":   return f"Grep({inputs.get('pattern','')})"
+    if name == "WebFetch":  return f"WebFetch({inputs.get('url','')[:60]})"
+    if name == "WebSearch": return f"WebSearch({inputs.get('query','')})"
+    return f"{name}({list(inputs.values())[:1]})"
+
+
+# ── Permission prompt ──────────────────────────────────────────────────────
+
+def ask_permission_interactive(desc: str, config: dict) -> bool:
+    try:
+        print()
+        ans = input(clr(f"  Allow: {desc}  [y/N/a(ccept-all)] ", "yellow")).strip().lower()
+        if ans == "a":
+            config["permission_mode"] = "accept-all"
+            ok("  Permission mode set to accept-all for this session.")
+            return True
+        return ans in ("y", "yes")
+    except (KeyboardInterrupt, EOFError):
+        print()
+        return False
+
+
+# ── Slash commands ─────────────────────────────────────────────────────────
+
+def cmd_help(_args: str, _state, _config) -> bool:
+    print(__doc__)
+    return True
+
+def cmd_clear(_args: str, state, _config) -> bool:
+    state.messages.clear()
+    state.turn_count = 0
+    ok("Conversation cleared.")
+    return True
+
+def cmd_model(args: str, _state, config) -> bool:
+    from providers import PROVIDERS, detect_provider
+    if not args:
+        model = config["model"]
+        pname = detect_provider(model)
+        info(f"Current model:    {model}  (provider: {pname})")
+        info("\nAvailable models by provider:")
+        for pn, pdata in PROVIDERS.items():
+            ms = pdata.get("models", [])
+            if ms:
+                info(f"  {pn:12s}  " + ", ".join(ms[:4]) + ("..." if len(ms) > 4 else ""))
+        info("\nFormat: 'provider/model' or just model name (auto-detected)")
+        info("  e.g. /model gpt-4o")
+        info("  e.g. /model ollama/qwen2.5-coder")
+        info("  e.g. /model kimi:moonshot-v1-32k")
+    else:
+        # Accept both "ollama/model" and "ollama:model" syntax
+        m = args.strip().replace(":", "/", 1)
+        config["model"] = m
+        pname = detect_provider(m)
+        ok(f"Model set to {m}  (provider: {pname})")
+        from config import save_config
+        save_config(config)
+    return True
+
+def cmd_config(args: str, _state, config) -> bool:
+    from config import save_config
+    if not args:
+        display = {k: v for k, v in config.items() if k != "api_key"}
+        print(json.dumps(display, indent=2))
+    elif "=" in args:
+        key, _, val = args.partition("=")
+        key, val = key.strip(), val.strip()
+        # Type coercion
+        if val.lower() in ("true", "false"):
+            val = val.lower() == "true"
+        elif val.isdigit():
+            val = int(val)
+        config[key] = val
+        save_config(config)
+        ok(f"Set {key} = {val}")
+    else:
+        k = args.strip()
+        v = config.get(k, "(not set)")
+        info(f"{k} = {v}")
+    return True
+
+def cmd_save(args: str, state, _config) -> bool:
+    from config import SESSIONS_DIR
+    fname = args.strip() or f"session_{datetime.now().strftime('%Y%m%d_%H%M%S')}.json"
+    path = Path(fname) if "/" in fname else SESSIONS_DIR / fname
+    data = {
+        "messages": [
+            m if not isinstance(m.get("content"), list) else
+            {**m, "content": [
+                b if isinstance(b, dict) else b.model_dump()
+                for b in m["content"]
+            ]}
+            for m in state.messages
+        ],
+        "turn_count": state.turn_count,
+        "total_input_tokens": state.total_input_tokens,
+        "total_output_tokens": state.total_output_tokens,
+    }
+    path.write_text(json.dumps(data, indent=2, default=str))
+    ok(f"Session saved to {path}")
+    return True
+
+def cmd_load(args: str, state, _config) -> bool:
+    from config import SESSIONS_DIR
+    if not args.strip():
+        # List available sessions
+        sessions = sorted(SESSIONS_DIR.glob("*.json"))
+        if not sessions:
+            info("No saved sessions found.")
+        else:
+            info("Saved sessions:")
+            for s in sessions:
+                info(f"  {s.name}")
+        return True
+    fname = args.strip()
+    path = Path(fname) if "/" in fname else SESSIONS_DIR / fname
+    if not path.exists():
+        err(f"File not found: {path}")
+        return True
+    data = json.loads(path.read_text())
+    state.messages = data.get("messages", [])
+    state.turn_count = data.get("turn_count", 0)
+    state.total_input_tokens = data.get("total_input_tokens", 0)
+    state.total_output_tokens = data.get("total_output_tokens", 0)
+    ok(f"Session loaded from {path} ({len(state.messages)} messages)")
+    return True
+
+def cmd_history(_args: str, state, _config) -> bool:
+    if not state.messages:
+        info("(empty conversation)")
+        return True
+    for i, m in enumerate(state.messages):
+        role = clr(m["role"].upper(), "bold",
+                   "cyan" if m["role"] == "user" else "green")
+        content = m["content"]
+        if isinstance(content, str):
+            print(f"[{i}] {role}: {content[:200]}")
+        elif isinstance(content, list):
+            for block in content:
+                if isinstance(block, dict):
+                    btype = block.get("type", "")
+                else:
+                    btype = getattr(block, "type", "")
+                if btype == "text":
+                    text = block.get("text", "") if isinstance(block, dict) else block.text
+                    print(f"[{i}] {role}: {text[:200]}")
+                elif btype == "tool_use":
+                    name = block.get("name", "") if isinstance(block, dict) else block.name
+                    print(f"[{i}] {role}: [tool_use: {name}]")
+                elif btype == "tool_result":
+                    cval = block.get("content", "") if isinstance(block, dict) else block.content
+                    print(f"[{i}] {role}: [tool_result: {str(cval)[:100]}]")
+    return True
+
+def cmd_context(_args: str, state, config) -> bool:
+    import anthropic
+    # Rough token estimate: 4 chars ≈ 1 token
+    msg_chars = sum(
+        len(str(m.get("content", ""))) for m in state.messages
+    )
+    est_tokens = msg_chars // 4
+    info(f"Messages:         {len(state.messages)}")
+    info(f"Estimated tokens: ~{est_tokens:,}")
+    info(f"Model:            {config['model']}")
+    info(f"Max tokens:       {config['max_tokens']:,}")
+    return True
+
+def cmd_cost(_args: str, state, config) -> bool:
+    from config import calc_cost
+    cost = calc_cost(config["model"],
+                     state.total_input_tokens,
+                     state.total_output_tokens)
+    info(f"Input tokens:  {state.total_input_tokens:,}")
+    info(f"Output tokens: {state.total_output_tokens:,}")
+    info(f"Est. cost:     ${cost:.4f} USD")
+    return True
+
+def cmd_verbose(_args: str, _state, config) -> bool:
+    config["verbose"] = not config.get("verbose", False)
+    state_str = "ON" if config["verbose"] else "OFF"
+    ok(f"Verbose mode: {state_str}")
+    return True
+
+def cmd_thinking(_args: str, _state, config) -> bool:
+    config["thinking"] = not config.get("thinking", False)
+    state_str = "ON" if config["thinking"] else "OFF"
+    ok(f"Extended thinking: {state_str}")
+    return True
+
+def cmd_permissions(args: str, _state, config) -> bool:
+    from config import save_config
+    modes = ["auto", "accept-all", "manual"]
+    if not args.strip():
+        info(f"Permission mode: {config.get('permission_mode','auto')}")
+        info(f"Available modes: {', '.join(modes)}")
+    else:
+        m = args.strip()
+        if m not in modes:
+            err(f"Unknown mode: {m}. Choose: {', '.join(modes)}")
+        else:
+            config["permission_mode"] = m
+            save_config(config)
+            ok(f"Permission mode set to: {m}")
+    return True
+
+def cmd_cwd(args: str, _state, _config) -> bool:
+    if not args.strip():
+        info(f"Working directory: {os.getcwd()}")
+    else:
+        p = args.strip()
+        try:
+            os.chdir(p)
+            ok(f"Changed directory to: {os.getcwd()}")
+        except Exception as e:
+            err(str(e))
+    return True
+
+def cmd_exit(_args: str, _state, _config) -> bool:
+    ok("Goodbye!")
+    sys.exit(0)
+
+COMMANDS = {
+    "help":        cmd_help,
+    "clear":       cmd_clear,
+    "model":       cmd_model,
+    "config":      cmd_config,
+    "save":        cmd_save,
+    "load":        cmd_load,
+    "history":     cmd_history,
+    "context":     cmd_context,
+    "cost":        cmd_cost,
+    "verbose":     cmd_verbose,
+    "thinking":    cmd_thinking,
+    "permissions": cmd_permissions,
+    "cwd":         cmd_cwd,
+    "exit":        cmd_exit,
+    "quit":        cmd_exit,
+}
+
+
+def handle_slash(line: str, state, config) -> bool:
+    """Handle /command [args]. Returns True if handled."""
+    if not line.startswith("/"):
+        return False
+    parts = line[1:].split(None, 1)
+    if not parts:
+        return False
+    cmd = parts[0].lower()
+    args = parts[1] if len(parts) > 1 else ""
+    handler = COMMANDS.get(cmd)
+    if handler:
+        handler(args, state, config)
+        return True
+    err(f"Unknown command: /{cmd}  (type /help for commands)")
+    return True
+
+
+# ── Input history setup ────────────────────────────────────────────────────
+
+def setup_readline(history_file: Path):
+    try:
+        readline.read_history_file(str(history_file))
+    except FileNotFoundError:
+        pass
+    readline.set_history_length(1000)
+    atexit.register(readline.write_history_file, str(history_file))
+
+    # Tab-complete slash commands
+    commands = [f"/{c}" for c in COMMANDS]
+    def completer(text: str, state: int):
+        matches = [c for c in commands if c.startswith(text)]
+        return matches[state] if state < len(matches) else None
+    readline.set_completer(completer)
+    readline.parse_and_bind("tab: complete")
+
+
+# ── Main REPL ──────────────────────────────────────────────────────────────
+
+def repl(config: dict, initial_prompt: str = None):
+    from config import HISTORY_FILE
+    from context import build_system_prompt
+    from agent import AgentState, run, TextChunk, ThinkingChunk, ToolStart, ToolEnd, TurnDone, PermissionRequest
+
+    setup_readline(HISTORY_FILE)
+    state = AgentState()
+    verbose = config.get("verbose", False)
+
+    # Banner
+    if not initial_prompt:
+        from providers import detect_provider
+        model    = config["model"]
+        pname    = detect_provider(model)
+        model_clr = clr(model, "cyan", "bold")
+        prov_clr  = clr(f"({pname})", "dim")
+        pmode     = clr(config.get("permission_mode", "auto"), "yellow")
+        print(clr("╭─ Nano Claude Code ──────────────────────────────╮", "dim"))
+        print(clr("│  Model: ", "dim") + model_clr + " " + prov_clr)
+        print(clr("│  Permissions: ", "dim") + pmode)
+        print(clr("│  /model to switch provider · /help for commands │", "dim"))
+        print(clr("╰──────────────────────────────────────────────────╯", "dim"))
+        print()
+
+    def run_query(user_input: str):
+        nonlocal verbose
+        verbose = config.get("verbose", False)
+
+        # Rebuild system prompt each turn (picks up cwd changes, etc.)
+        system_prompt = build_system_prompt()
+
+        print(clr("\n╭─ Claude ", "dim") + clr("●", "green") + clr(" ─────────────────────────", "dim"))
+        print(clr("│ ", "dim"), end="", flush=True)
+
+        thinking_started = False
+
+        for event in run(user_input, state, config, system_prompt):
+            if isinstance(event, TextChunk):
+                stream_text(event.text)
+
+            elif isinstance(event, ThinkingChunk):
+                if verbose:
+                    if not thinking_started:
+                        print(clr("\n  [thinking]", "dim"))
+                        thinking_started = True
+                    stream_thinking(event.text, verbose)
+
+            elif isinstance(event, ToolStart):
+                flush_response()
+                print_tool_start(event.name, event.inputs, verbose)
+
+            elif isinstance(event, PermissionRequest):
+                event.granted = ask_permission_interactive(event.description, config)
+
+            elif isinstance(event, ToolEnd):
+                print_tool_end(event.name, event.result, verbose)
+                # Print prefix for next text
+                print(clr("│ ", "dim"), end="", flush=True)
+
+            elif isinstance(event, TurnDone):
+                if verbose:
+                    print(clr(
+                        f"\n  [tokens: +{event.input_tokens} in / "
+                        f"+{event.output_tokens} out]", "dim"
+                    ))
+
+        flush_response()
+        print(clr("╰──────────────────────────────────────────────", "dim"))
+        print()
+
+    # ── Main loop ──
+    if initial_prompt:
+        try:
+            run_query(initial_prompt)
+        except KeyboardInterrupt:
+            print()
+        return
+
+    while True:
+        try:
+            cwd_short = Path.cwd().name
+            prompt = clr(f"\n[{cwd_short}] ", "dim") + clr("❯ ", "cyan", "bold")
+            user_input = input(prompt).strip()
+        except (EOFError, KeyboardInterrupt):
+            print()
+            ok("Goodbye!")
+            sys.exit(0)
+
+        if not user_input:
+            continue
+        if handle_slash(user_input, state, config):
+            continue
+
+        try:
+            run_query(user_input)
+        except KeyboardInterrupt:
+            print(clr("\n  (interrupted)", "yellow"))
+            # Keep conversation history up to the interruption
+
+
+# ── Entry point ────────────────────────────────────────────────────────────
+
+def main():
+    parser = argparse.ArgumentParser(
+        prog="nano_claude",
+        description="Nano Claude Code — minimal Python Claude Code implementation",
+        add_help=False,
+    )
+    parser.add_argument("prompt", nargs="*", help="Initial prompt (non-interactive)")
+    parser.add_argument("-p", "--print", "--print-output",
+                        dest="print_mode", action="store_true",
+                        help="Non-interactive mode: run prompt and exit")
+    parser.add_argument("-m", "--model", help="Override model")
+    parser.add_argument("--accept-all", action="store_true",
+                        help="Never ask permission (accept all operations)")
+    parser.add_argument("--verbose", action="store_true",
+                        help="Show thinking + token counts")
+    parser.add_argument("--thinking", action="store_true",
+                        help="Enable extended thinking")
+    parser.add_argument("--version", action="store_true", help="Print version")
+    parser.add_argument("-h", "--help", action="store_true", help="Show help")
+
+    args = parser.parse_args()
+
+    if args.version:
+        print(f"nano claude code v{VERSION}")
+        sys.exit(0)
+
+    if args.help:
+        print(__doc__)
+        sys.exit(0)
+
+    from config import load_config, save_config, has_api_key
+    from providers import detect_provider, PROVIDERS
+
+    config = load_config()
+
+    # Apply CLI overrides first (so key check uses the right provider)
+    if args.model:
+        config["model"] = args.model.replace(":", "/", 1)
+    if args.accept_all:
+        config["permission_mode"] = "accept-all"
+    if args.verbose:
+        config["verbose"] = True
+    if args.thinking:
+        config["thinking"] = True
+
+    # Check API key for active provider (warn only, don't block local providers)
+    if not has_api_key(config):
+        pname = detect_provider(config["model"])
+        prov  = PROVIDERS.get(pname, {})
+        env   = prov.get("api_key_env", "")
+        if env:   # local providers like ollama have no env key requirement
+            warn(f"No API key found for provider '{pname}'. "
+                 f"Set {env} or run: /config {pname}_api_key=YOUR_KEY")
+
+    initial = " ".join(args.prompt) if args.prompt else None
+    if args.print_mode and not initial:
+        err("--print requires a prompt argument")
+        sys.exit(1)
+
+    repl(config, initial_prompt=initial)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/nano-claude-code/providers.py b/nano-claude-code/providers.py
new file mode 100644
index 0000000..1fb4f9a
--- /dev/null
+++ b/nano-claude-code/providers.py
@@ -0,0 +1,487 @@
+"""
+Multi-provider support for nano claude.
+
+Supported providers:
+  anthropic  — Claude (claude-opus-4-6, claude-sonnet-4-6, ...)
+  openai     — GPT (gpt-4o, o3-mini, ...)
+  gemini     — Google Gemini (gemini-2.0-flash, gemini-1.5-pro, ...)
+  kimi       — Moonshot AI (moonshot-v1-8k/32k/128k)
+  qwen       — Alibaba DashScope (qwen-max, qwen-plus, ...)
+  zhipu      — Zhipu GLM (glm-4, glm-4-plus, ...)
+  deepseek   — DeepSeek (deepseek-chat, deepseek-reasoner, ...)
+  ollama     — Local Ollama (llama3.3, qwen2.5-coder, ...)
+  lmstudio   — Local LM Studio (any loaded model)
+  custom     — Any OpenAI-compatible endpoint
+
+Model string formats:
+  "claude-opus-4-6"          auto-detected → anthropic
+  "gpt-4o"                   auto-detected → openai
+  "ollama/qwen2.5-coder"     explicit provider prefix
+  "custom/my-model"          uses CUSTOM_BASE_URL from config
+"""
+from __future__ import annotations
+import json
+from typing import Generator
+
+# ── Provider registry ──────────────────────────────────────────────────────
+
+PROVIDERS: dict[str, dict] = {
+    "anthropic": {
+        "type":       "anthropic",
+        "api_key_env": "ANTHROPIC_API_KEY",
+        "models": [
+            "claude-opus-4-6", "claude-sonnet-4-6", "claude-haiku-4-5-20251001",
+            "claude-opus-4-5", "claude-sonnet-4-5",
+            "claude-3-5-sonnet-20241022", "claude-3-5-haiku-20241022",
+        ],
+    },
+    "openai": {
+        "type":       "openai",
+        "api_key_env": "OPENAI_API_KEY",
+        "base_url":   "https://api.openai.com/v1",
+        "models": [
+            "gpt-4o", "gpt-4o-mini", "gpt-4-turbo",
+            "o3-mini", "o1", "o1-mini",
+        ],
+    },
+    "gemini": {
+        "type":       "openai",
+        "api_key_env": "GEMINI_API_KEY",
+        "base_url":   "https://generativelanguage.googleapis.com/v1beta/openai/",
+        "models": [
+            "gemini-2.5-pro-preview-03-25",
+            "gemini-2.0-flash", "gemini-2.0-flash-lite",
+            "gemini-1.5-pro", "gemini-1.5-flash",
+        ],
+    },
+    "kimi": {
+        "type":       "openai",
+        "api_key_env": "MOONSHOT_API_KEY",
+        "base_url":   "https://api.moonshot.cn/v1",
+        "models": [
+            "moonshot-v1-8k", "moonshot-v1-32k", "moonshot-v1-128k",
+            "kimi-latest",
+        ],
+    },
+    "qwen": {
+        "type":       "openai",
+        "api_key_env": "DASHSCOPE_API_KEY",
+        "base_url":   "https://dashscope.aliyuncs.com/compatible-mode/v1",
+        "models": [
+            "qwen-max", "qwen-plus", "qwen-turbo", "qwen-long",
+            "qwen2.5-72b-instruct", "qwen2.5-coder-32b-instruct",
+            "qwq-32b",
+        ],
+    },
+    "zhipu": {
+        "type":       "openai",
+        "api_key_env": "ZHIPU_API_KEY",
+        "base_url":   "https://open.bigmodel.cn/api/paas/v4/",
+        "models": [
+            "glm-4-plus", "glm-4", "glm-4-flash", "glm-4-air",
+            "glm-z1-flash",
+        ],
+    },
+    "deepseek": {
+        "type":       "openai",
+        "api_key_env": "DEEPSEEK_API_KEY",
+        "base_url":   "https://api.deepseek.com/v1",
+        "models": [
+            "deepseek-chat", "deepseek-coder", "deepseek-reasoner",
+        ],
+    },
+    "ollama": {
+        "type":       "openai",
+        "api_key_env": None,
+        "base_url":   "http://localhost:11434/v1",
+        "api_key":    "ollama",
+        "models": [
+            "llama3.3", "llama3.2", "phi4", "mistral", "mixtral",
+            "qwen2.5-coder", "deepseek-r1", "gemma3",
+        ],
+    },
+    "lmstudio": {
+        "type":       "openai",
+        "api_key_env": None,
+        "base_url":   "http://localhost:1234/v1",
+        "api_key":    "lm-studio",
+        "models": [],   # dynamic, depends on loaded model
+    },
+    "custom": {
+        "type":       "openai",
+        "api_key_env": "CUSTOM_API_KEY",
+        "base_url":   None,   # read from config["custom_base_url"]
+        "models": [],
+    },
+}
+
+# Cost per million tokens (approximate, fallback to 0 for unknown)
+COSTS = {
+    "claude-opus-4-6":          (15.0, 75.0),
+    "claude-sonnet-4-6":        (3.0,  15.0),
+    "claude-haiku-4-5-20251001": (0.8,  4.0),
+    "gpt-4o":                   (2.5,  10.0),
+    "gpt-4o-mini":              (0.15,  0.6),
+    "o3-mini":                  (1.1,   4.4),
+    "gemini-2.0-flash":         (0.075, 0.3),
+    "gemini-1.5-pro":           (1.25,  5.0),
+    "gemini-2.5-pro-preview-03-25": (1.25, 10.0),
+    "moonshot-v1-8k":           (1.0,   3.0),
+    "moonshot-v1-32k":          (2.4,   7.0),
+    "moonshot-v1-128k":         (8.0,  24.0),
+    "qwen-max":                 (2.4,   9.6),
+    "qwen-plus":                (0.4,   1.2),
+    "deepseek-chat":            (0.27,  1.1),
+    "deepseek-reasoner":        (0.55,  2.19),
+    "glm-4-plus":               (0.7,   0.7),
+}
+
+# Auto-detection: prefix → provider name
+_PREFIXES = [
+    ("claude-",       "anthropic"),
+    ("gpt-",          "openai"),
+    ("o1",            "openai"),
+    ("o3",            "openai"),
+    ("gemini-",       "gemini"),
+    ("moonshot-",     "kimi"),
+    ("kimi-",         "kimi"),
+    ("qwen",          "qwen"),  # qwen-max, qwen2.5-...
+    ("qwq-",          "qwen"),
+    ("glm-",          "zhipu"),
+    ("deepseek-",     "deepseek"),
+    ("llama",         "ollama"),
+    ("mistral",       "ollama"),
+    ("phi",           "ollama"),
+    ("gemma",         "ollama"),
+]
+
+
+def detect_provider(model: str) -> str:
+    """Return provider name for a model string.
+    Supports 'provider/model' explicit format, or auto-detect by prefix."""
+    if "/" in model:
+        return model.split("/", 1)[0]
+    for prefix, pname in _PREFIXES:
+        if model.lower().startswith(prefix):
+            return pname
+    return "openai"   # fallback
+
+
+def bare_model(model: str) -> str:
+    """Strip 'provider/' prefix if present."""
+    return model.split("/", 1)[1] if "/" in model else model
+
+
+def get_api_key(provider_name: str, config: dict) -> str:
+    prov = PROVIDERS.get(provider_name, {})
+    # 1. Check config dict (e.g. config["kimi_api_key"])
+    cfg_key = config.get(f"{provider_name}_api_key", "")
+    if cfg_key:
+        return cfg_key
+    # 2. Check env var
+    env_var = prov.get("api_key_env")
+    if env_var:
+        import os
+        return os.environ.get(env_var, "")
+    # 3. Hardcoded (for local providers)
+    return prov.get("api_key", "")
+
+
+def calc_cost(model: str, in_tok: int, out_tok: int) -> float:
+    ic, oc = COSTS.get(bare_model(model), (0.0, 0.0))
+    return (in_tok * ic + out_tok * oc) / 1_000_000
+
+
+# ── Tool schema conversion ─────────────────────────────────────────────────
+
+def tools_to_openai(tool_schemas: list) -> list:
+    """Convert Anthropic-style tool schemas to OpenAI function-calling format."""
+    return [
+        {
+            "type": "function",
+            "function": {
+                "name":        t["name"],
+                "description": t["description"],
+                "parameters":  t["input_schema"],
+            },
+        }
+        for t in tool_schemas
+    ]
+
+
+# ── Message format conversion ──────────────────────────────────────────────
+#
+# Internal "neutral" message format:
+#   {"role": "user",      "content": "text"}
+#   {"role": "assistant", "content": "text", "tool_calls": [
+#       {"id": "...", "name": "...", "input": {...}}
+#   ]}
+#   {"role": "tool", "tool_call_id": "...", "name": "...", "content": "..."}
+
+def messages_to_anthropic(messages: list) -> list:
+    """Convert neutral messages → Anthropic API format."""
+    result = []
+    i = 0
+    while i < len(messages):
+        m = messages[i]
+        role = m["role"]
+
+        if role == "user":
+            result.append({"role": "user", "content": m["content"]})
+            i += 1
+
+        elif role == "assistant":
+            blocks = []
+            text = m.get("content", "")
+            if text:
+                blocks.append({"type": "text", "text": text})
+            for tc in m.get("tool_calls", []):
+                blocks.append({
+                    "type":  "tool_use",
+                    "id":    tc["id"],
+                    "name":  tc["name"],
+                    "input": tc["input"],
+                })
+            result.append({"role": "assistant", "content": blocks})
+            i += 1
+
+        elif role == "tool":
+            # Collect consecutive tool results into one user message
+            tool_blocks = []
+            while i < len(messages) and messages[i]["role"] == "tool":
+                t = messages[i]
+                tool_blocks.append({
+                    "type":        "tool_result",
+                    "tool_use_id": t["tool_call_id"],
+                    "content":     t["content"],
+                })
+                i += 1
+            result.append({"role": "user", "content": tool_blocks})
+
+        else:
+            i += 1
+
+    return result
+
+
+def messages_to_openai(messages: list) -> list:
+    """Convert neutral messages → OpenAI API format."""
+    result = []
+    for m in messages:
+        role = m["role"]
+
+        if role == "user":
+            result.append({"role": "user", "content": m["content"]})
+
+        elif role == "assistant":
+            msg: dict = {"role": "assistant", "content": m.get("content") or None}
+            tcs = m.get("tool_calls", [])
+            if tcs:
+                msg["tool_calls"] = [
+                    {
+                        "id":   tc["id"],
+                        "type": "function",
+                        "function": {
+                            "name":      tc["name"],
+                            "arguments": json.dumps(tc["input"], ensure_ascii=False),
+                        },
+                    }
+                    for tc in tcs
+                ]
+            result.append(msg)
+
+        elif role == "tool":
+            result.append({
+                "role":         "tool",
+                "tool_call_id": m["tool_call_id"],
+                "content":      m["content"],
+            })
+
+    return result
+
+
+# ── Streaming adapters ─────────────────────────────────────────────────────
+
+class TextChunk:
+    def __init__(self, text): self.text = text
+
+class ThinkingChunk:
+    def __init__(self, text): self.text = text
+
+class AssistantTurn:
+    """Completed assistant turn with text + tool_calls."""
+    def __init__(self, text, tool_calls, in_tokens, out_tokens):
+        self.text        = text
+        self.tool_calls  = tool_calls   # list of {id, name, input}
+        self.in_tokens   = in_tokens
+        self.out_tokens  = out_tokens
+
+
+def stream_anthropic(
+    api_key: str,
+    model: str,
+    system: str,
+    messages: list,
+    tool_schemas: list,
+    config: dict,
+) -> Generator:
+    """Stream from Anthropic API. Yields TextChunk/ThinkingChunk, then AssistantTurn."""
+    import anthropic as _ant
+    client = _ant.Anthropic(api_key=api_key)
+
+    kwargs = {
+        "model":      model,
+        "max_tokens": config.get("max_tokens", 8192),
+        "system":     system,
+        "messages":   messages_to_anthropic(messages),
+        "tools":      tool_schemas,
+    }
+    if config.get("thinking"):
+        kwargs["thinking"] = {
+            "type":          "enabled",
+            "budget_tokens": config.get("thinking_budget", 10000),
+        }
+
+    tool_calls = []
+    text       = ""
+
+    with client.messages.stream(**kwargs) as stream:
+        for event in stream:
+            etype = getattr(event, "type", None)
+            if etype == "content_block_delta":
+                delta = event.delta
+                dtype = getattr(delta, "type", None)
+                if dtype == "text_delta":
+                    text += delta.text
+                    yield TextChunk(delta.text)
+                elif dtype == "thinking_delta":
+                    yield ThinkingChunk(delta.thinking)
+
+        final = stream.get_final_message()
+        for block in final.content:
+            if block.type == "tool_use":
+                tool_calls.append({
+                    "id":    block.id,
+                    "name":  block.name,
+                    "input": block.input,
+                })
+
+        yield AssistantTurn(
+            text, tool_calls,
+            final.usage.input_tokens,
+            final.usage.output_tokens,
+        )
+
+
+def stream_openai_compat(
+    api_key: str,
+    base_url: str,
+    model: str,
+    system: str,
+    messages: list,
+    tool_schemas: list,
+    config: dict,
+) -> Generator:
+    """Stream from any OpenAI-compatible API. Yields TextChunk, then AssistantTurn."""
+    from openai import OpenAI
+    client = OpenAI(api_key=api_key or "dummy", base_url=base_url)
+
+    oai_messages = [{"role": "system", "content": system}] + messages_to_openai(messages)
+
+    kwargs: dict = {
+        "model":    model,
+        "messages": oai_messages,
+        "stream":   True,
+    }
+    if tool_schemas and not config.get("no_tools"):
+        kwargs["tools"] = tools_to_openai(tool_schemas)
+        # "auto" requires vLLM --enable-auto-tool-choice; omit if server doesn't support it
+        if not config.get("disable_tool_choice"):
+            kwargs["tool_choice"] = "auto"
+    if config.get("max_tokens"):
+        kwargs["max_tokens"] = config["max_tokens"]
+
+    text          = ""
+    tool_buf: dict = {}   # index → {id, name, args_str}
+    in_tok = out_tok = 0
+
+    stream = client.chat.completions.create(**kwargs)
+    for chunk in stream:
+        if not chunk.choices:
+            # usage-only chunk (some providers send this last)
+            if hasattr(chunk, "usage") and chunk.usage:
+                in_tok  = chunk.usage.prompt_tokens
+                out_tok = chunk.usage.completion_tokens
+            continue
+
+        choice = chunk.choices[0]
+        delta  = choice.delta
+
+        if delta.content:
+            text += delta.content
+            yield TextChunk(delta.content)
+
+        if delta.tool_calls:
+            for tc in delta.tool_calls:
+                idx = tc.index
+                if idx not in tool_buf:
+                    tool_buf[idx] = {"id": "", "name": "", "args": ""}
+                if tc.id:
+                    tool_buf[idx]["id"] = tc.id
+                if tc.function:
+                    if tc.function.name:
+                        tool_buf[idx]["name"] += tc.function.name
+                    if tc.function.arguments:
+                        tool_buf[idx]["args"] += tc.function.arguments
+
+        # Some providers include usage in the last chunk
+        if hasattr(chunk, "usage") and chunk.usage:
+            in_tok  = chunk.usage.prompt_tokens  or in_tok
+            out_tok = chunk.usage.completion_tokens or out_tok
+
+    tool_calls = []
+    for idx in sorted(tool_buf):
+        v = tool_buf[idx]
+        try:
+            inp = json.loads(v["args"]) if v["args"] else {}
+        except json.JSONDecodeError:
+            inp = {"_raw": v["args"]}
+        tool_calls.append({"id": v["id"] or f"call_{idx}", "name": v["name"], "input": inp})
+
+    yield AssistantTurn(text, tool_calls, in_tok, out_tok)
+
+
+def stream(
+    model: str,
+    system: str,
+    messages: list,
+    tool_schemas: list,
+    config: dict,
+) -> Generator:
+    """
+    Unified streaming entry point.
+    Auto-detects provider from model string.
+    Yields: TextChunk | ThinkingChunk | AssistantTurn
+    """
+    provider_name = detect_provider(model)
+    model_name    = bare_model(model)
+    prov          = PROVIDERS.get(provider_name, PROVIDERS["openai"])
+    api_key       = get_api_key(provider_name, config)
+
+    if prov["type"] == "anthropic":
+        yield from stream_anthropic(api_key, model_name, system, messages, tool_schemas, config)
+    else:
+        import os as _os
+        if provider_name == "custom":
+            base_url = (config.get("custom_base_url")
+                        or _os.environ.get("CUSTOM_BASE_URL", ""))
+            if not base_url:
+                raise ValueError(
+                    "custom provider requires a base_url. "
+                    "Set CUSTOM_BASE_URL env var or run: /config custom_base_url=http://..."
+                )
+        else:
+            base_url = prov.get("base_url", "https://api.openai.com/v1")
+        yield from stream_openai_compat(
+            api_key, base_url, model_name, system, messages, tool_schemas, config
+        )
diff --git a/nano-claude-code/requirements.txt b/nano-claude-code/requirements.txt
new file mode 100644
index 0000000..e945798
--- /dev/null
+++ b/nano-claude-code/requirements.txt
@@ -0,0 +1,4 @@
+anthropic>=0.40.0
+openai>=1.30.0
+httpx>=0.27.0
+rich>=13.0.0
diff --git a/nano-claude-code/tools.py b/nano-claude-code/tools.py
new file mode 100644
index 0000000..0efd516
--- /dev/null
+++ b/nano-claude-code/tools.py
@@ -0,0 +1,359 @@
+"""Tool definitions and implementations for nano claude."""
+import os
+import re
+import glob as _glob
+import subprocess
+from pathlib import Path
+from typing import Callable, Optional
+
+# ── Tool JSON schemas (sent to Claude API) ─────────────────────────────────
+
+TOOL_SCHEMAS = [
+    {
+        "name": "Read",
+        "description": (
+            "Read a file's contents. Returns content with line numbers "
+            "(format: 'N\\tline'). Use limit/offset to read large files in chunks."
+        ),
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "file_path": {"type": "string", "description": "Absolute file path"},
+                "limit":     {"type": "integer", "description": "Max lines to read"},
+                "offset":    {"type": "integer", "description": "Start line (0-indexed)"},
+            },
+            "required": ["file_path"],
+        },
+    },
+    {
+        "name": "Write",
+        "description": "Write content to a file, creating parent directories as needed.",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "file_path": {"type": "string"},
+                "content":   {"type": "string"},
+            },
+            "required": ["file_path", "content"],
+        },
+    },
+    {
+        "name": "Edit",
+        "description": (
+            "Replace exact text in a file. old_string must match exactly (including whitespace). "
+            "If old_string appears multiple times, use replace_all=true or add more context."
+        ),
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "file_path":   {"type": "string"},
+                "old_string":  {"type": "string", "description": "Exact text to replace"},
+                "new_string":  {"type": "string", "description": "Replacement text"},
+                "replace_all": {"type": "boolean", "description": "Replace all occurrences"},
+            },
+            "required": ["file_path", "old_string", "new_string"],
+        },
+    },
+    {
+        "name": "Bash",
+        "description": "Execute a shell command. Returns stdout+stderr. Stateless (no cd persistence).",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "command": {"type": "string"},
+                "timeout": {"type": "integer", "description": "Seconds before timeout (default 30)"},
+            },
+            "required": ["command"],
+        },
+    },
+    {
+        "name": "Glob",
+        "description": "Find files matching a glob pattern. Returns sorted list of matching paths.",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "pattern": {"type": "string", "description": "Glob pattern e.g. **/*.py"},
+                "path":    {"type": "string", "description": "Base directory (default: cwd)"},
+            },
+            "required": ["pattern"],
+        },
+    },
+    {
+        "name": "Grep",
+        "description": "Search file contents with regex using ripgrep (falls back to grep).",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "pattern":      {"type": "string", "description": "Regex pattern"},
+                "path":         {"type": "string", "description": "File or directory to search"},
+                "glob":         {"type": "string", "description": "File filter e.g. *.py"},
+                "output_mode":  {
+                    "type": "string",
+                    "enum": ["content", "files_with_matches", "count"],
+                    "description": "content=matching lines, files_with_matches=file paths, count=match counts",
+                },
+                "case_insensitive": {"type": "boolean"},
+                "context":      {"type": "integer", "description": "Lines of context around matches"},
+            },
+            "required": ["pattern"],
+        },
+    },
+    {
+        "name": "WebFetch",
+        "description": "Fetch a URL and return its text content (HTML stripped).",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "url":    {"type": "string"},
+                "prompt": {"type": "string", "description": "Hint for what to extract"},
+            },
+            "required": ["url"],
+        },
+    },
+    {
+        "name": "WebSearch",
+        "description": "Search the web via DuckDuckGo and return top results.",
+        "input_schema": {
+            "type": "object",
+            "properties": {
+                "query": {"type": "string"},
+            },
+            "required": ["query"],
+        },
+    },
+]
+
+# ── Safe bash commands (never ask permission) ───────────────────────────────
+
+_SAFE_PREFIXES = (
+    "ls", "cat", "head", "tail", "wc", "pwd", "echo", "printf", "date",
+    "which", "type", "env", "printenv", "uname", "whoami", "id",
+    "git log", "git status", "git diff", "git show", "git branch",
+    "git remote", "git stash list", "git tag",
+    "find ", "grep ", "rg ", "ag ", "fd ",
+    "python ", "python3 ", "node ", "ruby ", "perl ",
+    "pip show", "pip list", "npm list", "cargo metadata",
+    "df ", "du ", "free ", "top -bn", "ps ",
+    "curl -I", "curl --head",
+)
+
+def _is_safe_bash(cmd: str) -> bool:
+    c = cmd.strip()
+    return any(c.startswith(p) for p in _SAFE_PREFIXES)
+
+
+# ── Tool implementations ───────────────────────────────────────────────────
+
+def _read(file_path: str, limit: int = None, offset: int = None) -> str:
+    p = Path(file_path)
+    if not p.exists():
+        return f"Error: file not found: {file_path}"
+    if p.is_dir():
+        return f"Error: {file_path} is a directory"
+    try:
+        lines = p.read_text(errors="replace").splitlines(keepends=True)
+        start = offset or 0
+        chunk = lines[start:start + limit] if limit else lines[start:]
+        if not chunk:
+            return "(empty file)"
+        return "".join(f"{start + i + 1}\t{l}" for i, l in enumerate(chunk))
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _write(file_path: str, content: str) -> str:
+    p = Path(file_path)
+    try:
+        p.parent.mkdir(parents=True, exist_ok=True)
+        p.write_text(content)
+        lc = content.count("\n") + (1 if content and not content.endswith("\n") else 0)
+        return f"Wrote {lc} lines to {file_path}"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _edit(file_path: str, old_string: str, new_string: str, replace_all: bool = False) -> str:
+    p = Path(file_path)
+    if not p.exists():
+        return f"Error: file not found: {file_path}"
+    try:
+        content = p.read_text()
+        count = content.count(old_string)
+        if count == 0:
+            return "Error: old_string not found in file"
+        if count > 1 and not replace_all:
+            return (f"Error: old_string appears {count} times. "
+                    "Provide more context to make it unique, or use replace_all=true.")
+        new_content = content.replace(old_string, new_string) if replace_all else \
+                      content.replace(old_string, new_string, 1)
+        p.write_text(new_content)
+        return f"Replaced {'all ' + str(count) if replace_all else '1'} occurrence(s) in {file_path}"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _bash(command: str, timeout: int = 30) -> str:
+    try:
+        r = subprocess.run(
+            command, shell=True, capture_output=True, text=True,
+            timeout=timeout, cwd=os.getcwd(),
+        )
+        out = r.stdout
+        if r.stderr:
+            out += ("\n" if out else "") + "[stderr]\n" + r.stderr
+        return out.strip() or "(no output)"
+    except subprocess.TimeoutExpired:
+        return f"Error: timed out after {timeout}s"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _glob(pattern: str, path: str = None) -> str:
+    base = Path(path) if path else Path.cwd()
+    try:
+        matches = sorted(base.glob(pattern))
+        if not matches:
+            return "No files matched"
+        return "\n".join(str(m) for m in matches[:500])
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _has_rg() -> bool:
+    try:
+        subprocess.run(["rg", "--version"], capture_output=True, check=True)
+        return True
+    except Exception:
+        return False
+
+
+def _grep(pattern: str, path: str = None, glob: str = None,
+          output_mode: str = "files_with_matches",
+          case_insensitive: bool = False, context: int = 0) -> str:
+    use_rg = _has_rg()
+    cmd = ["rg" if use_rg else "grep", "--no-heading"]
+    if case_insensitive:
+        cmd.append("-i")
+    if output_mode == "files_with_matches":
+        cmd.append("-l")
+    elif output_mode == "count":
+        cmd.append("-c")
+    else:
+        cmd.append("-n")
+        if context:
+            cmd += ["-C", str(context)]
+    if glob:
+        cmd += (["--glob", glob] if use_rg else ["--include", glob])
+    cmd.append(pattern)
+    cmd.append(path or str(Path.cwd()))
+    try:
+        r = subprocess.run(cmd, capture_output=True, text=True, timeout=30)
+        out = r.stdout.strip()
+        return out[:20000] if out else "No matches found"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _webfetch(url: str, prompt: str = None) -> str:
+    try:
+        import httpx
+        r = httpx.get(url, headers={"User-Agent": "NanoClaude/1.0"},
+                      timeout=30, follow_redirects=True)
+        r.raise_for_status()
+        ct = r.headers.get("content-type", "")
+        if "html" in ct:
+            text = re.sub(r"<script[^>]*>.*?</script>", "", r.text,
+                          flags=re.DOTALL | re.IGNORECASE)
+            text = re.sub(r"<style[^>]*>.*?</style>", "", text,
+                          flags=re.DOTALL | re.IGNORECASE)
+            text = re.sub(r"<[^>]+>", " ", text)
+            text = re.sub(r"\s+", " ", text).strip()
+        else:
+            text = r.text
+        return text[:25000]
+    except ImportError:
+        return "Error: httpx not installed — run: pip install httpx"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+def _websearch(query: str) -> str:
+    try:
+        import httpx
+        url = "https://html.duckduckgo.com/html/"
+        r = httpx.get(url, params={"q": query},
+                      headers={"User-Agent": "Mozilla/5.0 (compatible)"},
+                      timeout=30, follow_redirects=True)
+        titles   = re.findall(r'class="result__title"[^>]*>.*?<a[^>]*href="([^"]+)"[^>]*>(.*?)</a>',
+                               r.text, re.DOTALL)
+        snippets = re.findall(r'class="result__snippet"[^>]*>(.*?)</div>', r.text, re.DOTALL)
+        results = []
+        for i, (link, title) in enumerate(titles[:8]):
+            t = re.sub(r"<[^>]+>", "", title).strip()
+            s = re.sub(r"<[^>]+>", "", snippets[i]).strip() if i < len(snippets) else ""
+            results.append(f"**{t}**\n{link}\n{s}")
+        return "\n\n".join(results) if results else "No results found"
+    except ImportError:
+        return "Error: httpx not installed — run: pip install httpx"
+    except Exception as e:
+        return f"Error: {e}"
+
+
+# ── Dispatcher ─────────────────────────────────────────────────────────────
+
+def execute_tool(
+    name: str,
+    inputs: dict,
+    permission_mode: str = "auto",
+    ask_permission: Optional[Callable[[str], bool]] = None,
+) -> str:
+    """Dispatch tool execution; ask permission for write/destructive ops."""
+
+    def _check(desc: str) -> bool:
+        """Return True if action is allowed."""
+        if permission_mode == "accept-all":
+            return True
+        if ask_permission:
+            return ask_permission(desc)
+        return True  # headless: allow everything
+
+    if name == "Read":
+        return _read(inputs["file_path"], inputs.get("limit"), inputs.get("offset"))
+
+    elif name == "Write":
+        if not _check(f"Write to {inputs['file_path']}"):
+            return "Denied: user rejected write operation"
+        return _write(inputs["file_path"], inputs["content"])
+
+    elif name == "Edit":
+        if not _check(f"Edit {inputs['file_path']}"):
+            return "Denied: user rejected edit operation"
+        return _edit(inputs["file_path"], inputs["old_string"],
+                     inputs["new_string"], inputs.get("replace_all", False))
+
+    elif name == "Bash":
+        cmd = inputs["command"]
+        if permission_mode != "accept-all" and not _is_safe_bash(cmd):
+            if not _check(f"Bash: {cmd}"):
+                return "Denied: user rejected bash command"
+        return _bash(cmd, inputs.get("timeout", 30))
+
+    elif name == "Glob":
+        return _glob(inputs["pattern"], inputs.get("path"))
+
+    elif name == "Grep":
+        return _grep(
+            inputs["pattern"], inputs.get("path"), inputs.get("glob"),
+            inputs.get("output_mode", "files_with_matches"),
+            inputs.get("case_insensitive", False),
+            inputs.get("context", 0),
+        )
+
+    elif name == "WebFetch":
+        return _webfetch(inputs["url"], inputs.get("prompt"))
+
+    elif name == "WebSearch":
+        return _websearch(inputs["query"])
+
+    else:
+        return f"Unknown tool: {name}"