From 633488e0c08c9bcb1e4c28e744a274d072ac9540 Mon Sep 17 00:00:00 2001
From: ygd58 <buraysandro9@gmail.com>
Date: Sat, 14 Mar 2026 07:58:03 +0100
Subject: [PATCH] fix(tools): preserve MCP toolsets when saving platform tool
 config

_save_platform_tools() overwrote the entire platform_toolsets list with
only the toolsets known to CONFIGURABLE_TOOLSETS. This silently dropped
any MCP server toolsets that users had added manually to config.yaml.

Fix: collect any existing toolset keys that are not in CONFIGURABLE_TOOLSETS
and append them back after the wizard's selections are written. This ensures
MCP toolsets survive a hermes tools save.

Fixes #1247
---
 hermes_cli/tools_config.py            | 24 +++++++++-
 tests/hermes_cli/test_tools_config.py | 64 ++++++++++++++++++++++++++-
 2 files changed, 84 insertions(+), 4 deletions(-)

diff --git a/hermes_cli/tools_config.py b/hermes_cli/tools_config.py
index f12a4b39..b819fafa 100644
--- a/hermes_cli/tools_config.py
+++ b/hermes_cli/tools_config.py
@@ -354,9 +354,29 @@ def _get_platform_tools(config: dict, platform: str) -> Set[str]:
 
 
 def _save_platform_tools(config: dict, platform: str, enabled_toolset_keys: Set[str]):
-    """Save the selected toolset keys for a platform to config."""
+    """Save the selected toolset keys for a platform to config.
+
+    Preserves any non-configurable toolset entries (like MCP server names)
+    that were already in the config for this platform.
+    """
     config.setdefault("platform_toolsets", {})
-    config["platform_toolsets"][platform] = sorted(enabled_toolset_keys)
+
+    # Get the set of all configurable toolset keys
+    configurable_keys = {ts_key for ts_key, _, _ in CONFIGURABLE_TOOLSETS}
+
+    # Get existing toolsets for this platform
+    existing_toolsets = config.get("platform_toolsets", {}).get(platform, [])
+    if not isinstance(existing_toolsets, list):
+        existing_toolsets = []
+
+    # Preserve any entries that are NOT configurable toolsets (i.e. MCP server names)
+    preserved_entries = {
+        entry for entry in existing_toolsets
+        if entry not in configurable_keys
+    }
+
+    # Merge preserved entries with new enabled toolsets
+    config["platform_toolsets"][platform] = sorted(enabled_toolset_keys | preserved_entries)
     save_config(config)
 
 
diff --git a/tests/hermes_cli/test_tools_config.py b/tests/hermes_cli/test_tools_config.py
index 92e1e60c..4aee5947 100644
--- a/tests/hermes_cli/test_tools_config.py
+++ b/tests/hermes_cli/test_tools_config.py
@@ -1,6 +1,13 @@
 """Tests for hermes_cli.tools_config platform tool persistence."""
 
-from hermes_cli.tools_config import _get_platform_tools, _platform_toolset_summary, _toolset_has_keys
+from unittest.mock import patch
+
+from hermes_cli.tools_config import (
+    _get_platform_tools,
+    _platform_toolset_summary,
+    _save_platform_tools,
+    _toolset_has_keys,
+)
 
 
 def test_get_platform_tools_uses_default_when_platform_not_configured():
@@ -31,7 +38,7 @@ def test_platform_toolset_summary_uses_explicit_platform_list():
 def test_toolset_has_keys_for_vision_accepts_codex_auth(tmp_path, monkeypatch):
     monkeypatch.setenv("HERMES_HOME", str(tmp_path))
     (tmp_path / "auth.json").write_text(
-        '{"active_provider":"openai-codex","providers":{"openai-codex":{"tokens":{"access_token":"codex-access-token","refresh_token":"codex-refresh-token"}}}}'
+        '{"active_provider":"openai-codex","providers":{"openai-codex":{"tokens":{"access_token": "codex-...oken","refresh_token": "codex-...oken"}}}}'
     )
     monkeypatch.delenv("OPENROUTER_API_KEY", raising=False)
     monkeypatch.delenv("OPENAI_BASE_URL", raising=False)
@@ -40,3 +47,56 @@ def test_toolset_has_keys_for_vision_accepts_codex_auth(tmp_path, monkeypatch):
     monkeypatch.delenv("CONTEXT_VISION_PROVIDER", raising=False)
 
     assert _toolset_has_keys("vision") is True
+
+
+def test_save_platform_tools_preserves_mcp_server_names():
+    """Ensure MCP server names are preserved when saving platform tools.
+
+    Regression test for https://github.com/NousResearch/hermes-agent/issues/1247
+    """
+    config = {
+        "platform_toolsets": {
+            "cli": ["web", "terminal", "time", "github", "custom-mcp-server"]
+        }
+    }
+
+    new_selection = {"web", "browser"}
+
+    with patch("hermes_cli.tools_config.save_config"):
+        _save_platform_tools(config, "cli", new_selection)
+
+    saved_toolsets = config["platform_toolsets"]["cli"]
+
+    assert "time" in saved_toolsets
+    assert "github" in saved_toolsets
+    assert "custom-mcp-server" in saved_toolsets
+    assert "web" in saved_toolsets
+    assert "browser" in saved_toolsets
+    assert "terminal" not in saved_toolsets
+
+
+def test_save_platform_tools_handles_empty_existing_config():
+    """Saving platform tools works when no existing config exists."""
+    config = {}
+
+    with patch("hermes_cli.tools_config.save_config"):
+        _save_platform_tools(config, "telegram", {"web", "terminal"})
+
+    saved_toolsets = config["platform_toolsets"]["telegram"]
+    assert "web" in saved_toolsets
+    assert "terminal" in saved_toolsets
+
+
+def test_save_platform_tools_handles_invalid_existing_config():
+    """Saving platform tools works when existing config is not a list."""
+    config = {
+        "platform_toolsets": {
+            "cli": "invalid-string-value"
+        }
+    }
+
+    with patch("hermes_cli.tools_config.save_config"):
+        _save_platform_tools(config, "cli", {"web"})
+
+    saved_toolsets = config["platform_toolsets"]["cli"]
+    assert "web" in saved_toolsets