feat: add /tools disable/enable/list slash commands with session reset (#1652)

Add in-session tool management via /tools disable/enable/list, plus
hermes tools list/disable/enable CLI subcommands. Supports both
built-in toolsets (web, memory) and MCP tools (github:create_issue).

To preserve prompt caching, /tools disable/enable in a chat session
saves the change to config and resets the session cleanly — the user
is asked to confirm before the reset happens.

Also improves prefix matching: /qui now dispatches to /quit instead
of showing ambiguous when longer skill commands like /quint-pipeline
are installed.

Based on PR #1520 by @YanSte.

Co-authored-by: Yannick Stephan <YanSte@users.noreply.github.com>

cli.py

@@ -2481,7 +2481,69 @@ class HermesCLI:
         
         print(f"  Total: {len(tools)} tools  ヽ(^o^)ノ")
         print()
-    
+
+    def _handle_tools_command(self, cmd: str):
+        """Handle /tools [list|disable|enable] slash commands.
+
+        /tools (no args) shows the tool list.
+        /tools list shows enabled/disabled status per toolset.
+        /tools disable/enable saves the change to config and resets
+        the session so the new tool set takes effect cleanly (no
+        prompt-cache breakage mid-conversation).
+        """
+        import shlex
+        from argparse import Namespace
+        from hermes_cli.tools_config import tools_disable_enable_command
+
+        try:
+            parts = shlex.split(cmd)
+        except ValueError:
+            parts = cmd.split()
+
+        subcommand = parts[1] if len(parts) > 1 else ""
+        if subcommand not in ("list", "disable", "enable"):
+            self.show_tools()
+            return
+
+        if subcommand == "list":
+            tools_disable_enable_command(
+                Namespace(tools_action="list", platform="cli"))
+            return
+
+        names = parts[2:]
+        if not names:
+            print(f"(._.) Usage: /tools {subcommand} <name> [name ...]")
+            print(f"  Built-in toolset:  /tools {subcommand} web")
+            print(f"  MCP tool:          /tools {subcommand} github:create_issue")
+            return
+
+        # Confirm session reset before applying
+        verb = "Disable" if subcommand == "disable" else "Enable"
+        label = ", ".join(names)
+        _cprint(f"{_GOLD}{verb} {label}?{_RST}")
+        _cprint(f"{_DIM}This will save to config and reset your session so the "
+                f"change takes effect cleanly.{_RST}")
+        try:
+            answer = input("  Continue? [y/N] ").strip().lower()
+        except (EOFError, KeyboardInterrupt):
+            print()
+            _cprint(f"{_DIM}Cancelled.{_RST}")
+            return
+
+        if answer not in ("y", "yes"):
+            _cprint(f"{_DIM}Cancelled.{_RST}")
+            return
+
+        tools_disable_enable_command(
+            Namespace(tools_action=subcommand, names=names, platform="cli"))
+
+        # Reset session so the new tool config is picked up from a clean state
+        from hermes_cli.tools_config import _get_platform_tools
+        from hermes_cli.config import load_config
+        self.enabled_toolsets = _get_platform_tools(load_config(), "cli")
+        self.new_session()
+        _cprint(f"{_DIM}Session reset. New tool configuration is active.{_RST}")
+
     def show_toolsets(self):
         """Display available toolsets with kawaii ASCII art."""
         all_toolsets = get_all_toolsets()
@@ -3279,7 +3341,7 @@ class HermesCLI:
         elif canonical == "help":
             self.show_help()
         elif canonical == "tools":
-            self.show_tools()
+            self._handle_tools_command(cmd_original)
         elif canonical == "toolsets":
             self.show_toolsets()
         elif canonical == "config":
@@ -3610,6 +3672,18 @@ class HermesCLI:
                 typed_base = cmd_lower.split()[0]
                 all_known = set(COMMANDS) | set(_skill_commands)
                 matches = [c for c in all_known if c.startswith(typed_base)]
+                if len(matches) > 1:
+                    # Prefer an exact match (typed the full command name)
+                    exact = [c for c in matches if c == typed_base]
+                    if len(exact) == 1:
+                        matches = exact
+                    else:
+                        # Prefer the unique shortest match:
+                        # /qui → /quit (5) wins over /quint-pipeline (15)
+                        min_len = min(len(c) for c in matches)
+                        shortest = [c for c in matches if len(c) == min_len]
+                        if len(shortest) == 1:
+                            matches = shortest
                 if len(matches) == 1:
                     # Expand the prefix to the full command name, preserving arguments.
                     # Guard against redispatching the same token to avoid infinite

hermes_cli/commands.py

@@ -92,8 +92,8 @@ COMMAND_REGISTRY: list[CommandDef] = [
                args_hint="[on|off|tts|status]", subcommands=("on", "off", "tts", "status")),
 
     # Tools & Skills
-    CommandDef("tools", "List available tools", "Tools & Skills",
-               cli_only=True),
+    CommandDef("tools", "Manage tools: /tools [list|disable|enable] [name...]", "Tools & Skills",
+               args_hint="[list|disable|enable] [name...]", cli_only=True),
     CommandDef("toolsets", "List available toolsets", "Tools & Skills",
                cli_only=True),
     CommandDef("skills", "Search, install, inspect, or manage skills",

hermes_cli/main.py

@@ -3147,17 +3147,66 @@ For more help on a command:
     tools_parser = subparsers.add_parser(
         "tools",
         help="Configure which tools are enabled per platform",
-        description="Interactive tool configuration — enable/disable tools for CLI, Telegram, Discord, etc."
+        description=(
+            "Enable, disable, or list tools for CLI, Telegram, Discord, etc.\n\n"
+            "Built-in toolsets use plain names (e.g. web, memory).\n"
+            "MCP tools use server:tool notation (e.g. github:create_issue).\n\n"
+            "Run 'hermes tools' with no subcommand for the interactive configuration UI."
+        ),
     )
     tools_parser.add_argument(
         "--summary",
         action="store_true",
         help="Print a summary of enabled tools per platform and exit"
     )
+    tools_sub = tools_parser.add_subparsers(dest="tools_action")
+
+    # hermes tools list [--platform cli]
+    tools_list_p = tools_sub.add_parser(
+        "list",
+        help="Show all tools and their enabled/disabled status",
+    )
+    tools_list_p.add_argument(
+        "--platform", default="cli",
+        help="Platform to show (default: cli)",
+    )
+
+    # hermes tools disable <name...> [--platform cli]
+    tools_disable_p = tools_sub.add_parser(
+        "disable",
+        help="Disable toolsets or MCP tools",
+    )
+    tools_disable_p.add_argument(
+        "names", nargs="+", metavar="NAME",
+        help="Toolset name (e.g. web) or MCP tool in server:tool form",
+    )
+    tools_disable_p.add_argument(
+        "--platform", default="cli",
+        help="Platform to apply to (default: cli)",
+    )
+
+    # hermes tools enable <name...> [--platform cli]
+    tools_enable_p = tools_sub.add_parser(
+        "enable",
+        help="Enable toolsets or MCP tools",
+    )
+    tools_enable_p.add_argument(
+        "names", nargs="+", metavar="NAME",
+        help="Toolset name or MCP tool in server:tool form",
+    )
+    tools_enable_p.add_argument(
+        "--platform", default="cli",
+        help="Platform to apply to (default: cli)",
+    )
 
     def cmd_tools(args):
-        from hermes_cli.tools_config import tools_command
-        tools_command(args)
+        action = getattr(args, "tools_action", None)
+        if action in ("list", "disable", "enable"):
+            from hermes_cli.tools_config import tools_disable_enable_command
+            tools_disable_enable_command(args)
+        else:
+            from hermes_cli.tools_config import tools_command
+            tools_command(args)
 
     tools_parser.set_defaults(func=cmd_tools)
     # =========================================================================

hermes_cli/tools_config.py

@@ -1088,3 +1088,114 @@ def tools_command(args=None, first_install: bool = False, config: dict = None):
     print(color("  Tool configuration saved to ~/.hermes/config.yaml", Colors.DIM))
     print(color("  Changes take effect on next 'hermes' or gateway restart.", Colors.DIM))
     print()
+
+
+# ─── Non-interactive disable/enable ──────────────────────────────────────────
+
+
+def _apply_toolset_change(config: dict, platform: str, toolset_names: List[str], action: str):
+    """Add or remove built-in toolsets for a platform."""
+    enabled = _get_platform_tools(config, platform)
+    if action == "disable":
+        updated = enabled - set(toolset_names)
+    else:
+        updated = enabled | set(toolset_names)
+    _save_platform_tools(config, platform, updated)
+
+
+def _apply_mcp_change(config: dict, targets: List[str], action: str) -> Set[str]:
+    """Add or remove specific MCP tools from a server's exclude list.
+
+    Returns the set of server names that were not found in config.
+    """
+    failed_servers: Set[str] = set()
+    mcp_servers = config.get("mcp_servers") or {}
+
+    for target in targets:
+        server_name, tool_name = target.split(":", 1)
+        if server_name not in mcp_servers:
+            failed_servers.add(server_name)
+            continue
+        tools_cfg = mcp_servers[server_name].setdefault("tools", {})
+        exclude = list(tools_cfg.get("exclude") or [])
+        if action == "disable":
+            if tool_name not in exclude:
+                exclude.append(tool_name)
+        else:
+            exclude = [t for t in exclude if t != tool_name]
+        tools_cfg["exclude"] = exclude
+
+    return failed_servers
+
+
+def _print_tools_list(enabled_toolsets: set, mcp_servers: dict, platform: str = "cli"):
+    """Print a summary of enabled/disabled toolsets and MCP tool filters."""
+    print(f"Built-in toolsets ({platform}):")
+    for ts_key, label, _ in CONFIGURABLE_TOOLSETS:
+        status = (color("✓ enabled", Colors.GREEN) if ts_key in enabled_toolsets
+                  else color("✗ disabled", Colors.RED))
+        print(f"  {status}  {ts_key}  {color(label, Colors.DIM)}")
+
+    if mcp_servers:
+        print()
+        print("MCP servers:")
+        for srv_name, srv_cfg in mcp_servers.items():
+            tools_cfg = srv_cfg.get("tools") or {}
+            exclude = tools_cfg.get("exclude") or []
+            include = tools_cfg.get("include") or []
+            if include:
+                _print_info(f"{srv_name}  [include only: {', '.join(include)}]")
+            elif exclude:
+                _print_info(f"{srv_name}  [excluded: {color(', '.join(exclude), Colors.YELLOW)}]")
+            else:
+                _print_info(f"{srv_name}  {color('all tools enabled', Colors.DIM)}")
+
+
+def tools_disable_enable_command(args):
+    """Enable, disable, or list tools for a platform.
+
+    Built-in toolsets use plain names (e.g. ``web``, ``memory``).
+    MCP tools use ``server:tool`` notation (e.g. ``github:create_issue``).
+    """
+    action = args.tools_action
+    platform = getattr(args, "platform", "cli")
+    config = load_config()
+
+    if platform not in PLATFORMS:
+        _print_error(f"Unknown platform '{platform}'. Valid: {', '.join(PLATFORMS)}")
+        return
+
+    if action == "list":
+        _print_tools_list(_get_platform_tools(config, platform),
+                          config.get("mcp_servers") or {}, platform)
+        return
+
+    targets: List[str] = args.names
+    toolset_targets = [t for t in targets if ":" not in t]
+    mcp_targets = [t for t in targets if ":" in t]
+
+    valid_toolsets = {ts_key for ts_key, _, _ in CONFIGURABLE_TOOLSETS}
+    unknown_toolsets = [t for t in toolset_targets if t not in valid_toolsets]
+    if unknown_toolsets:
+        for name in unknown_toolsets:
+            _print_error(f"Unknown toolset '{name}'")
+        toolset_targets = [t for t in toolset_targets if t in valid_toolsets]
+
+    if toolset_targets:
+        _apply_toolset_change(config, platform, toolset_targets, action)
+
+    failed_servers: Set[str] = set()
+    if mcp_targets:
+        failed_servers = _apply_mcp_change(config, mcp_targets, action)
+        for srv in failed_servers:
+            _print_error(f"MCP server '{srv}' not found in config")
+
+    save_config(config)
+
+    successful = [
+        t for t in targets
+        if t not in unknown_toolsets and (":" not in t or t.split(":")[0] not in failed_servers)
+    ]
+    if successful:
+        verb = "Disabled" if action == "disable" else "Enabled"
+        _print_success(f"{verb}: {', '.join(successful)}")

tests/hermes_cli/test_tools_disable_enable.py

@@ -0,0 +1,207 @@
+"""Tests for hermes tools disable/enable/list command (backend)."""
+from argparse import Namespace
+from unittest.mock import patch
+
+from hermes_cli.tools_config import tools_disable_enable_command
+
+
+# ── Built-in toolset disable ────────────────────────────────────────────────
+
+
+class TestToolsDisableBuiltin:
+
+    def test_disable_removes_toolset_from_platform(self):
+        config = {"platform_toolsets": {"cli": ["web", "memory", "terminal"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(tools_action="disable", names=["web"], platform="cli"))
+        saved = mock_save.call_args[0][0]
+        assert "web" not in saved["platform_toolsets"]["cli"]
+        assert "memory" in saved["platform_toolsets"]["cli"]
+
+    def test_disable_multiple_toolsets(self):
+        config = {"platform_toolsets": {"cli": ["web", "memory", "terminal"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(tools_action="disable", names=["web", "memory"], platform="cli"))
+        saved = mock_save.call_args[0][0]
+        assert "web" not in saved["platform_toolsets"]["cli"]
+        assert "memory" not in saved["platform_toolsets"]["cli"]
+        assert "terminal" in saved["platform_toolsets"]["cli"]
+
+    def test_disable_already_absent_is_idempotent(self):
+        config = {"platform_toolsets": {"cli": ["memory"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(tools_action="disable", names=["web"], platform="cli"))
+        saved = mock_save.call_args[0][0]
+        assert "web" not in saved["platform_toolsets"]["cli"]
+
+
+# ── Built-in toolset enable ─────────────────────────────────────────────────
+
+
+class TestToolsEnableBuiltin:
+
+    def test_enable_adds_toolset_to_platform(self):
+        config = {"platform_toolsets": {"cli": ["memory"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(tools_action="enable", names=["web"], platform="cli"))
+        saved = mock_save.call_args[0][0]
+        assert "web" in saved["platform_toolsets"]["cli"]
+
+    def test_enable_already_present_is_idempotent(self):
+        config = {"platform_toolsets": {"cli": ["web"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(tools_action="enable", names=["web"], platform="cli"))
+        saved = mock_save.call_args[0][0]
+        assert saved["platform_toolsets"]["cli"].count("web") == 1
+
+
+# ── MCP tool disable ────────────────────────────────────────────────────────
+
+
+class TestToolsDisableMcp:
+
+    def test_disable_adds_to_exclude_list(self):
+        config = {"mcp_servers": {"github": {"command": "npx"}}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["github:create_issue"], platform="cli")
+            )
+        saved = mock_save.call_args[0][0]
+        assert "create_issue" in saved["mcp_servers"]["github"]["tools"]["exclude"]
+
+    def test_disable_already_excluded_is_idempotent(self):
+        config = {"mcp_servers": {"github": {"tools": {"exclude": ["create_issue"]}}}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["github:create_issue"], platform="cli")
+            )
+        saved = mock_save.call_args[0][0]
+        assert saved["mcp_servers"]["github"]["tools"]["exclude"].count("create_issue") == 1
+
+    def test_disable_unknown_server_prints_error(self, capsys):
+        config = {"mcp_servers": {}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config"):
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["unknown:tool"], platform="cli")
+            )
+        out = capsys.readouterr().out
+        assert "MCP server 'unknown' not found in config" in out
+
+
+# ── MCP tool enable ──────────────────────────────────────────────────────────
+
+
+class TestToolsEnableMcp:
+
+    def test_enable_removes_from_exclude_list(self):
+        config = {"mcp_servers": {"github": {"tools": {"exclude": ["create_issue", "delete_branch"]}}}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(
+                Namespace(tools_action="enable", names=["github:create_issue"], platform="cli")
+            )
+        saved = mock_save.call_args[0][0]
+        assert "create_issue" not in saved["mcp_servers"]["github"]["tools"]["exclude"]
+        assert "delete_branch" in saved["mcp_servers"]["github"]["tools"]["exclude"]
+
+
+# ── Mixed targets ────────────────────────────────────────────────────────────
+
+
+class TestToolsMixedTargets:
+
+    def test_disable_builtin_and_mcp_together(self):
+        config = {
+            "platform_toolsets": {"cli": ["web", "memory"]},
+            "mcp_servers": {"github": {"command": "npx"}},
+        }
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(Namespace(
+                tools_action="disable",
+                names=["web", "github:create_issue"],
+                platform="cli",
+            ))
+        saved = mock_save.call_args[0][0]
+        assert "web" not in saved["platform_toolsets"]["cli"]
+        assert "create_issue" in saved["mcp_servers"]["github"]["tools"]["exclude"]
+
+
+# ── List output ──────────────────────────────────────────────────────────────
+
+
+class TestToolsList:
+
+    def test_list_shows_enabled_toolsets(self, capsys):
+        config = {"platform_toolsets": {"cli": ["web", "memory"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config):
+            tools_disable_enable_command(Namespace(tools_action="list", platform="cli"))
+        out = capsys.readouterr().out
+        assert "web" in out
+        assert "memory" in out
+
+    def test_list_shows_mcp_excluded_tools(self, capsys):
+        config = {
+            "mcp_servers": {"github": {"tools": {"exclude": ["create_issue"]}}},
+        }
+        with patch("hermes_cli.tools_config.load_config", return_value=config):
+            tools_disable_enable_command(Namespace(tools_action="list", platform="cli"))
+        out = capsys.readouterr().out
+        assert "github" in out
+        assert "create_issue" in out
+
+
+# ── Validation ───────────────────────────────────────────────────────────────
+
+
+class TestToolsValidation:
+
+    def test_unknown_platform_prints_error(self, capsys):
+        config = {}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config"):
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["web"], platform="invalid_platform")
+            )
+        out = capsys.readouterr().out
+        assert "Unknown platform 'invalid_platform'" in out
+
+    def test_unknown_toolset_prints_error(self, capsys):
+        config = {"platform_toolsets": {"cli": ["web"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config"):
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["nonexistent_toolset"], platform="cli")
+            )
+        out = capsys.readouterr().out
+        assert "Unknown toolset 'nonexistent_toolset'" in out
+
+    def test_unknown_toolset_does_not_corrupt_config(self):
+        config = {"platform_toolsets": {"cli": ["web", "memory"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["nonexistent_toolset"], platform="cli")
+            )
+        saved = mock_save.call_args[0][0]
+        assert "web" in saved["platform_toolsets"]["cli"]
+        assert "memory" in saved["platform_toolsets"]["cli"]
+
+    def test_mixed_valid_and_invalid_applies_valid_only(self):
+        config = {"platform_toolsets": {"cli": ["web", "memory"]}}
+        with patch("hermes_cli.tools_config.load_config", return_value=config), \
+             patch("hermes_cli.tools_config.save_config") as mock_save:
+            tools_disable_enable_command(
+                Namespace(tools_action="disable", names=["web", "bad_toolset"], platform="cli")
+            )
+        saved = mock_save.call_args[0][0]
+        assert "web" not in saved["platform_toolsets"]["cli"]
+        assert "memory" in saved["platform_toolsets"]["cli"]

tests/test_cli_prefix_matching.py

@@ -121,3 +121,40 @@ class TestSlashCommandPrefixMatching:
         mock_help.assert_called_once()
         printed = " ".join(str(c) for c in cli_obj.console.print.call_args_list)
         assert "Ambiguous" not in printed
+
+    def test_shortest_match_preferred_over_longer_skill(self):
+        """/qui should dispatch to /quit (5 chars) not report ambiguous with /quint-pipeline (15 chars)."""
+        cli_obj = _make_cli()
+        fake_skill = {"/quint-pipeline": {"name": "Quint Pipeline", "description": "test"}}
+
+        import cli as cli_mod
+        with patch.object(cli_mod, '_skill_commands', fake_skill):
+            # /quit is caught by the exact "/quit" branch → process_command returns False
+            result = cli_obj.process_command("/qui")
+
+        # Returns False because /quit was dispatched (exits chat loop)
+        assert result is False
+        printed = " ".join(str(c) for c in cli_obj.console.print.call_args_list)
+        assert "Ambiguous" not in printed
+
+    def test_tied_shortest_matches_still_ambiguous(self):
+        """/re matches /reset and /retry (both 6 chars) — no unique shortest, stays ambiguous."""
+        cli_obj = _make_cli()
+        printed = []
+        import cli as cli_mod
+        with patch.object(cli_mod, '_cprint', side_effect=lambda t: printed.append(t)):
+            cli_obj.process_command("/re")
+        combined = " ".join(printed)
+        assert "Ambiguous" in combined or "Did you mean" in combined
+
+    def test_exact_typed_name_dispatches_over_longer_match(self):
+        """/help typed with /help-extra skill installed → exact match wins."""
+        cli_obj = _make_cli()
+        fake_skill = {"/help-extra": {"name": "Help Extra", "description": ""}}
+        import cli as cli_mod
+        with patch.object(cli_mod, '_skill_commands', fake_skill), \
+             patch.object(cli_obj, 'show_help') as mock_help:
+            cli_obj.process_command("/help")
+        mock_help.assert_called_once()
+        printed = " ".join(str(c) for c in cli_obj.console.print.call_args_list)
+        assert "Ambiguous" not in printed

tests/test_cli_tools_command.py

@@ -0,0 +1,121 @@
+"""Tests for /tools slash command handler in the interactive CLI."""
+
+from unittest.mock import MagicMock, patch, call
+
+from cli import HermesCLI
+
+
+def _make_cli(enabled_toolsets=None):
+    """Build a minimal HermesCLI stub without running __init__."""
+    cli_obj = HermesCLI.__new__(HermesCLI)
+    cli_obj.enabled_toolsets = set(enabled_toolsets or ["web", "memory"])
+    cli_obj._command_running = False
+    cli_obj.console = MagicMock()
+    return cli_obj
+
+
+# ── /tools (no subcommand) ──────────────────────────────────────────────────
+
+
+class TestToolsSlashNoSubcommand:
+
+    def test_bare_tools_shows_tool_list(self):
+        cli_obj = _make_cli()
+        with patch.object(cli_obj, "show_tools") as mock_show:
+            cli_obj._handle_tools_command("/tools")
+        mock_show.assert_called_once()
+
+    def test_unknown_subcommand_falls_back_to_show_tools(self):
+        cli_obj = _make_cli()
+        with patch.object(cli_obj, "show_tools") as mock_show:
+            cli_obj._handle_tools_command("/tools foobar")
+        mock_show.assert_called_once()
+
+
+# ── /tools list ─────────────────────────────────────────────────────────────
+
+
+class TestToolsSlashList:
+
+    def test_list_calls_backend(self, capsys):
+        cli_obj = _make_cli()
+        with patch("hermes_cli.tools_config.load_config",
+                   return_value={"platform_toolsets": {"cli": ["web"]}}), \
+             patch("hermes_cli.tools_config.save_config"):
+            cli_obj._handle_tools_command("/tools list")
+        out = capsys.readouterr().out
+        assert "web" in out
+
+    def test_list_does_not_modify_enabled_toolsets(self):
+        """List is read-only — self.enabled_toolsets must not change."""
+        cli_obj = _make_cli(["web", "memory"])
+        with patch("hermes_cli.tools_config.load_config",
+                   return_value={"platform_toolsets": {"cli": ["web"]}}):
+            cli_obj._handle_tools_command("/tools list")
+        assert cli_obj.enabled_toolsets == {"web", "memory"}
+
+
+# ── /tools disable (session reset) ──────────────────────────────────────────
+
+
+class TestToolsSlashDisableWithReset:
+
+    def test_disable_confirms_then_resets_session(self):
+        cli_obj = _make_cli(["web", "memory"])
+        with patch("hermes_cli.tools_config.load_config",
+                   return_value={"platform_toolsets": {"cli": ["web", "memory"]}}), \
+             patch("hermes_cli.tools_config.save_config"), \
+             patch("hermes_cli.tools_config._get_platform_tools", return_value={"memory"}), \
+             patch("hermes_cli.config.load_config", return_value={}), \
+             patch.object(cli_obj, "new_session") as mock_reset, \
+             patch("builtins.input", return_value="y"):
+            cli_obj._handle_tools_command("/tools disable web")
+        mock_reset.assert_called_once()
+        assert "web" not in cli_obj.enabled_toolsets
+
+    def test_disable_cancelled_does_not_reset(self):
+        cli_obj = _make_cli(["web", "memory"])
+        with patch.object(cli_obj, "new_session") as mock_reset, \
+             patch("builtins.input", return_value="n"):
+            cli_obj._handle_tools_command("/tools disable web")
+        mock_reset.assert_not_called()
+        # Toolsets unchanged
+        assert cli_obj.enabled_toolsets == {"web", "memory"}
+
+    def test_disable_eof_cancels(self):
+        cli_obj = _make_cli(["web", "memory"])
+        with patch.object(cli_obj, "new_session") as mock_reset, \
+             patch("builtins.input", side_effect=EOFError):
+            cli_obj._handle_tools_command("/tools disable web")
+        mock_reset.assert_not_called()
+
+    def test_disable_missing_name_prints_usage(self, capsys):
+        cli_obj = _make_cli()
+        cli_obj._handle_tools_command("/tools disable")
+        out = capsys.readouterr().out
+        assert "Usage" in out
+
+
+# ── /tools enable (session reset) ───────────────────────────────────────────
+
+
+class TestToolsSlashEnableWithReset:
+
+    def test_enable_confirms_then_resets_session(self):
+        cli_obj = _make_cli(["memory"])
+        with patch("hermes_cli.tools_config.load_config",
+                   return_value={"platform_toolsets": {"cli": ["memory"]}}), \
+             patch("hermes_cli.tools_config.save_config"), \
+             patch("hermes_cli.tools_config._get_platform_tools", return_value={"memory", "web"}), \
+             patch("hermes_cli.config.load_config", return_value={}), \
+             patch.object(cli_obj, "new_session") as mock_reset, \
+             patch("builtins.input", return_value="y"):
+            cli_obj._handle_tools_command("/tools enable web")
+        mock_reset.assert_called_once()
+        assert "web" in cli_obj.enabled_toolsets
+
+    def test_enable_missing_name_prints_usage(self, capsys):
+        cli_obj = _make_cli()
+        cli_obj._handle_tools_command("/tools enable")
+        out = capsys.readouterr().out
+        assert "Usage" in out