fix: preserve Claude stdio MCP env

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- `apm install --target claude` now preserves self-defined stdio MCP `env` values from `apm.yml` and writes non-string values such as `PORT: 3000` and `DEBUG: false` as MCP-compatible strings. (#1222)
 - Pin `Path.home()` under unit tests via a session-scoped autouse conftest fixture, fixing 56 Windows runner failures on the new `windows-2025-vs2026` GitHub-hosted image where `USERPROFILE`/`HOMEDRIVE`+`HOMEPATH` are not seeded for pytest workers; also patch the `_check_and_notify_updates` import binding in the disabled-self-update test so it no longer races on the version-check cache. (#1270)
 - `apm install` now works on macOS git 2.53.0 (Homebrew): bare-cache commands switch to `--git-dir` to satisfy the `safe.bareRepository=explicit` default; fetched SHAs are pinned as synthetic refs so `git clone --local --shared` no longer silently omits them. (#1268)
 - Set the unit-test hermetic HOME at conftest import time so a single xdist worker on the `windows-2025-vs2026` runner can no longer race fixture setup and re-trigger the 53 `Path.home()` failures the session-scoped autouse fixture was supposed to prevent. (#1271)

src/apm_cli/adapters/client/copilot.py

@@ -93,6 +93,13 @@ def _has_env_placeholder(value):
     return bool(_COPILOT_ENV_RE.search(value))
 
 
+def _stringify_env_literal(value):
+    """Return MCP env literal values in the manifest ``map<string, string>`` shape."""
+    if isinstance(value, bool):
+        return str(value).lower()
+    return str(value)
+
+
 class CopilotClientAdapter(MCPClientAdapter):
     """Copilot CLI implementation of MCP client adapter.
 
@@ -745,8 +752,10 @@ def _resolve_environment_variables(self, env_vars, env_overrides=None):
             for name, raw_value in env_vars.items():
                 if not name:
                     continue
+                if raw_value is None:
+                    continue
                 if not isinstance(raw_value, str):
-                    translated[name] = raw_value
+                    translated[name] = _stringify_env_literal(raw_value)
                     continue
                 if _has_env_placeholder(raw_value):
                     self._last_legacy_angle_vars.update(_extract_legacy_angle_vars(raw_value))
@@ -788,6 +797,19 @@ def _resolve_environment_variables(self, env_vars, env_overrides=None):
             self._last_env_placeholder_keys = set(placeholder_keys)
             return resolved
 
+        if isinstance(env_vars, dict):
+            resolved = {}
+            for name, value in env_vars.items():
+                if not name:
+                    continue
+                if isinstance(value, str):
+                    resolved[name] = self._resolve_env_variable(
+                        name, value, env_overrides=env_overrides
+                    )
+                elif value is not None:
+                    resolved[name] = _stringify_env_literal(value)
+            return resolved
+
         import os
         import sys
 

tests/unit/test_claude_mcp.py

@@ -119,6 +119,36 @@ def test_update_config_tolerates_malformed_project_mcp_json(self):
         data = json.loads(self.mcp_path.read_text(encoding="utf-8"))
         self.assertIn("srv", data["mcpServers"])
 
+    def test_configure_self_defined_stdio_preserves_env(self):
+        with patch.object(self.adapter, "registry_client") as mock_registry:
+            mock_registry.find_server_by_reference.return_value = {
+                "name": "env-demo",
+                "_raw_stdio": {
+                    "command": "npx",
+                    "args": ["-y", "example-mcp"],
+                    "env": {
+                        "DEMO_ENV": "demo-value",
+                        "PORT": 3000,
+                        "DEBUG": False,
+                        "RATE": 0.5,
+                    },
+                },
+            }
+
+            ok = self.adapter.configure_mcp_server("env-demo")
+
+        self.assertTrue(ok)
+        data = json.loads(self.mcp_path.read_text(encoding="utf-8"))
+        self.assertEqual(
+            data["mcpServers"]["env-demo"]["env"],
+            {
+                "DEMO_ENV": "demo-value",
+                "PORT": "3000",
+                "DEBUG": "false",
+                "RATE": "0.5",
+            },
+        )
+
 
 class TestClaudeClientAdapterUser(unittest.TestCase):
     """User scope: ``~/.claude.json`` top-level ``mcpServers``."""

tests/unit/test_copilot_adapter.py

@@ -557,6 +557,18 @@ def test_dict_shaped_env_block_does_not_silently_drop(self):
         )
         self.assertEqual(set(result.keys()), {"FOO", "BAR"})
 
+    def test_dict_shaped_env_block_stringifies_literals_and_omits_none(self):
+        adapter = CopilotClientAdapter()
+        result = adapter._resolve_environment_variables(
+            {"PORT": 3000, "DEBUG": False, "RATE": 0.5, "OPTIONAL": None},
+            env_overrides=None,
+        )
+
+        self.assertEqual(
+            result,
+            {"PORT": "3000", "DEBUG": "false", "RATE": "0.5"},
+        )
+
 
 class TestCopilotInstallRunSummary(unittest.TestCase):
     """Issue #1152: aggregated post-install diagnostics.