Files
hermes-agent/tests/hermes_cli/test_mcp_tools_config.py
Teknium ce7418e274 feat: interactive MCP tool configuration in hermes tools (#1694)
Add the ability to selectively enable/disable individual MCP server
tools through the interactive 'hermes tools' TUI.

Changes:
- tools/mcp_tool.py: Add probe_mcp_server_tools() — lightweight function
  that temporarily connects to configured MCP servers, discovers their
  tools (names + descriptions), and disconnects. No registry side effects.

- hermes_cli/tools_config.py: Add 'Configure MCP tools' option to the
  interactive menu. When selected:
  1. Probes all enabled MCP servers for their available tools
  2. Shows a per-server curses checklist with tool descriptions
  3. Pre-selects tools based on existing include/exclude config
  4. Writes changes back as tools.exclude entries in config.yaml
  5. Reports which servers failed to connect

The existing CLI commands (hermes tools enable/disable server:tool)
continue to work unchanged. This adds the interactive TUI counterpart
so users can browse and toggle MCP tools visually.

Tests: 22 new tests covering probe function edge cases and interactive
flow (pre-selection, exclude/include modes, description truncation,
multi-server handling, error paths).
2026-03-17 03:48:44 -07:00

292 lines
9.4 KiB
Python

"""Tests for MCP tools interactive configuration in hermes_cli.tools_config."""
from types import SimpleNamespace
from unittest.mock import MagicMock, patch
from hermes_cli.tools_config import _configure_mcp_tools_interactive
# Patch targets: imports happen inside the function body, so patch at source
_PROBE = "tools.mcp_tool.probe_mcp_server_tools"
_CHECKLIST = "hermes_cli.curses_ui.curses_checklist"
_SAVE = "hermes_cli.tools_config.save_config"
def test_no_mcp_servers_prints_info(capsys):
"""Returns immediately when no MCP servers are configured."""
config = {}
_configure_mcp_tools_interactive(config)
captured = capsys.readouterr()
assert "No MCP servers configured" in captured.out
def test_all_servers_disabled_prints_info(capsys):
"""Returns immediately when all configured servers have enabled=false."""
config = {
"mcp_servers": {
"github": {"command": "npx", "enabled": False},
"slack": {"command": "npx", "enabled": "false"},
}
}
_configure_mcp_tools_interactive(config)
captured = capsys.readouterr()
assert "disabled" in captured.out
def test_probe_failure_shows_warning(capsys):
"""Shows warning when probe returns no tools."""
config = {"mcp_servers": {"github": {"command": "npx"}}}
with patch(_PROBE, return_value={}):
_configure_mcp_tools_interactive(config)
captured = capsys.readouterr()
assert "Could not discover" in captured.out
def test_probe_exception_shows_error(capsys):
"""Shows error when probe raises an exception."""
config = {"mcp_servers": {"github": {"command": "npx"}}}
with patch(_PROBE, side_effect=RuntimeError("MCP not installed")):
_configure_mcp_tools_interactive(config)
captured = capsys.readouterr()
assert "Failed to probe" in captured.out
def test_no_changes_when_checklist_cancelled(capsys):
"""No config changes when user cancels (ESC) the checklist."""
config = {
"mcp_servers": {
"github": {"command": "npx", "args": ["-y", "server-github"]},
}
}
tools = [("create_issue", "Create an issue"), ("search_repos", "Search repos")]
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, return_value={0, 1}), \
patch(_SAVE) as mock_save:
_configure_mcp_tools_interactive(config)
mock_save.assert_not_called()
captured = capsys.readouterr()
assert "no changes" in captured.out.lower()
def test_disabling_tool_writes_exclude_list(capsys):
"""Unchecking a tool adds it to the exclude list."""
config = {
"mcp_servers": {
"github": {"command": "npx"},
}
}
tools = [
("create_issue", "Create an issue"),
("delete_repo", "Delete a repo"),
("search_repos", "Search repos"),
]
# User unchecks delete_repo (index 1)
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, return_value={0, 2}), \
patch(_SAVE) as mock_save:
_configure_mcp_tools_interactive(config)
mock_save.assert_called_once()
tools_cfg = config["mcp_servers"]["github"]["tools"]
assert tools_cfg["exclude"] == ["delete_repo"]
assert "include" not in tools_cfg
def test_enabling_all_clears_filters(capsys):
"""Checking all tools clears both include and exclude lists."""
config = {
"mcp_servers": {
"github": {
"command": "npx",
"tools": {"exclude": ["delete_repo"], "include": ["create_issue"]},
},
}
}
tools = [("create_issue", "Create"), ("delete_repo", "Delete")]
# User checks all tools — pre_selected would be {0} (include mode),
# so returning {0, 1} is a change
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, return_value={0, 1}), \
patch(_SAVE) as mock_save:
_configure_mcp_tools_interactive(config)
mock_save.assert_called_once()
tools_cfg = config["mcp_servers"]["github"]["tools"]
assert "exclude" not in tools_cfg
assert "include" not in tools_cfg
def test_pre_selection_respects_existing_exclude(capsys):
"""Tools in exclude list start unchecked."""
config = {
"mcp_servers": {
"github": {
"command": "npx",
"tools": {"exclude": ["delete_repo"]},
},
}
}
tools = [("create_issue", "Create"), ("delete_repo", "Delete"), ("search", "Search")]
captured_pre_selected = {}
def fake_checklist(title, labels, pre_selected, **kwargs):
captured_pre_selected["value"] = set(pre_selected)
return pre_selected # No changes
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, side_effect=fake_checklist), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
# create_issue (0) and search (2) should be pre-selected, delete_repo (1) should not
assert captured_pre_selected["value"] == {0, 2}
def test_pre_selection_respects_existing_include(capsys):
"""Only tools in include list start checked."""
config = {
"mcp_servers": {
"github": {
"command": "npx",
"tools": {"include": ["search"]},
},
}
}
tools = [("create_issue", "Create"), ("delete_repo", "Delete"), ("search", "Search")]
captured_pre_selected = {}
def fake_checklist(title, labels, pre_selected, **kwargs):
captured_pre_selected["value"] = set(pre_selected)
return pre_selected # No changes
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, side_effect=fake_checklist), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
# Only search (2) should be pre-selected
assert captured_pre_selected["value"] == {2}
def test_multiple_servers_each_get_checklist(capsys):
"""Each server gets its own checklist."""
config = {
"mcp_servers": {
"github": {"command": "npx"},
"slack": {"url": "https://mcp.example.com"},
}
}
checklist_calls = []
def fake_checklist(title, labels, pre_selected, **kwargs):
checklist_calls.append(title)
return pre_selected # No changes
with patch(
_PROBE,
return_value={
"github": [("create_issue", "Create")],
"slack": [("send_message", "Send")],
},
), patch(_CHECKLIST, side_effect=fake_checklist), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
assert len(checklist_calls) == 2
assert any("github" in t for t in checklist_calls)
assert any("slack" in t for t in checklist_calls)
def test_failed_server_shows_warning(capsys):
"""Servers that fail to connect show warnings."""
config = {
"mcp_servers": {
"github": {"command": "npx"},
"broken": {"command": "nonexistent"},
}
}
# Only github succeeds
with patch(
_PROBE, return_value={"github": [("create_issue", "Create")]},
), patch(_CHECKLIST, return_value={0}), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
captured = capsys.readouterr()
assert "broken" in captured.out
def test_description_truncation_in_labels():
"""Long descriptions are truncated in checklist labels."""
config = {
"mcp_servers": {
"github": {"command": "npx"},
}
}
long_desc = "A" * 100
captured_labels = {}
def fake_checklist(title, labels, pre_selected, **kwargs):
captured_labels["value"] = labels
return pre_selected
with patch(
_PROBE, return_value={"github": [("my_tool", long_desc)]},
), patch(_CHECKLIST, side_effect=fake_checklist), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
label = captured_labels["value"][0]
assert "..." in label
assert len(label) < len(long_desc) + 30 # truncated + tool name + parens
def test_switching_from_include_to_exclude(capsys):
"""When user modifies selection, include list is replaced by exclude list."""
config = {
"mcp_servers": {
"github": {
"command": "npx",
"tools": {"include": ["create_issue"]},
},
}
}
tools = [("create_issue", "Create"), ("search", "Search"), ("delete", "Delete")]
# User selects create_issue and search (deselects delete)
# pre_selected would be {0} (only create_issue from include), so {0, 1} is a change
with patch(_PROBE, return_value={"github": tools}), \
patch(_CHECKLIST, return_value={0, 1}), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
tools_cfg = config["mcp_servers"]["github"]["tools"]
assert tools_cfg["exclude"] == ["delete"]
assert "include" not in tools_cfg
def test_empty_tools_server_skipped(capsys):
"""Server with no tools shows info message and skips checklist."""
config = {
"mcp_servers": {
"empty": {"command": "npx"},
}
}
checklist_calls = []
def fake_checklist(title, labels, pre_selected, **kwargs):
checklist_calls.append(title)
return pre_selected
with patch(_PROBE, return_value={"empty": []}), \
patch(_CHECKLIST, side_effect=fake_checklist), \
patch(_SAVE):
_configure_mcp_tools_interactive(config)
assert len(checklist_calls) == 0
captured = capsys.readouterr()
assert "no tools found" in captured.out