fix(mcp): ${CLAUDE_PLUGIN_ROOT} substitution + cortex-doctor mcp diagnostic

.claude-plugin/marketplace.json

@@ -6,14 +6,14 @@
   },
   "metadata": {
     "description": "Persistent memory and cognitive profiling plugins for Claude Code",
-    "version": "3.15.1"
+    "version": "3.15.2"
   },
   "plugins": [
     {
       "name": "cortex",
       "source": "./",
       "description": "Persistent memory and cognitive profiling for Claude Code — thermodynamic memory with heat/decay, intent-aware retrieval, biological plasticity, codebase intelligence, and cognitive profiling. 47 MCP tools with enriched schemas. PostgreSQL + pgvector in CLI mode; automatic SQLite fallback in Cowork/sandboxed mode. Curated wiki (ADRs, specs, lessons) with audit-artefact filtering. Consolidate is set-based SQL batched — decay/plasticity/pruning run 100-500× faster on large stores. Workflow graph with caller-qualified CALLS chains rendering full method-to-method dependencies (native tree-sitter, no AP required). Side panel humanized for non-technical users. Ingests codebase analysis (ai-automatised-pipeline) and PRDs (prd-spec-generator) into wiki + memory + knowledge graph. Docker image available.",
-      "version": "3.15.1",
+      "version": "3.15.2",
       "author": {
         "name": "Clement Deust",
         "email": "admin@ai-architect.tools"

.mcp.json

@@ -3,8 +3,8 @@
     "cortex": {
       "command": "python3",
       "args": [
-        "-c",
-        "import json,os; p=json.load(open(os.path.expanduser('~/.claude/plugins/installed_plugins.json')))['plugins']['cortex@cortex-plugins'][0]['installPath']; os.execvp('python3',['python3',os.path.join(p,'scripts','launcher.py'),'mcp_server'])"
+        "${CLAUDE_PLUGIN_ROOT}/scripts/launcher.py",
+        "mcp_server"
       ],
       "env": {
         "DATABASE_URL": "postgresql://localhost:5432/cortex",

CHANGELOG.md

@@ -6,6 +6,37 @@ adheres to [Semantic Versioning](https://semver.org/).
 
 ## [Unreleased]
 
+## [3.15.2] - 2026-05-09
+
+### Fixed
+- **MCP startup robustness** — Discord user reported the Cortex MCP server
+  failing to start with no actionable error. Root cause: `.mcp.json` used a
+  fragile `python -c` one-liner that read `~/.claude/plugins/installed_plugins.json`
+  to dynamically resolve the install path. The wrapper swallowed all
+  launcher startup errors invisibly and broke under: (a) plugin upgrade
+  leaving stale `installPath`, (b) custom marketplace install names, (c)
+  `python3` not on PATH, (d) any `installed_plugins.json` shape change by
+  Claude Code. `.mcp.json` now uses `${CLAUDE_PLUGIN_ROOT}/scripts/launcher.py`
+  — Anthropic's documented plugin substitution variable, already used by
+  every hook in this repo. The launcher self-orients via `__file__` so
+  manual installs continue to work.
+
+### Added
+- **`cortex-doctor mcp`** — new diagnostic subcommand for end-to-end MCP
+  startup checks. Tells the user *exactly* which check failed, what
+  command/path was tried, and the actual error string — no more silent
+  "✘ failed". Checks: python interpreter on PATH, `installed_plugins.json`
+  shape, `CLAUDE_PLUGIN_ROOT` env, launcher smoke probe (catches errors
+  the old `-c` wrapper hid), `DATABASE_URL`, critical Python deps. Use
+  `--json` for Discord-paste-friendly output.
+
+### Verification
+- 36 new tests added (`tests_py/test_doctor_mcp.py`,
+  `tests_py/scripts/test_launcher_resolution.py`); all pass.
+- Backward-compatible: `cortex-doctor` (no subcommand) preserves legacy
+  full-setup verification behaviour.
+- Platform-agnostic: no Windows/Mac-specific code paths.
+
 ## [3.15.1] - 2026-05-05
 
 ### Fixed

mcp_server/doctor.py

@@ -271,12 +271,29 @@ def _i10_config() -> Check:
 
 
 def run() -> int:
-    """Run all checks. Print a report. Return 0 on required-green, 1 otherwise.
-
-    Optional checks (``Check.optional=True``) warn on failure but do not
-    cause a non-zero exit. Only core-required checks (PG connection,
-    Python version, etc.) gate the exit code.
+    """Entry point. Dispatches to subcommand if given, else full check.
+
+    Subcommands:
+      (none)   Full setup verification (Python, PG, extensions, etc.)
+      mcp      MCP startup diagnostics (Discord-debug-friendly)
+               Flags:
+                 --json   Emit machine-readable JSON report
+                 --copy   Prepend a "paste me in Discord" header to the
+                          human output (useful for issue templates)
     """
+    argv = sys.argv[1:]
+    if argv and argv[0] == "mcp":
+        from mcp_server.doctor_mcp import run_mcp
+
+        flags = argv[1:]
+        json_output = "--json" in flags
+        copy_header = "--copy" in flags
+        return run_mcp(json_output=json_output, copy_header=copy_header)
+    return _run_full_check()
+
+
+def _run_full_check() -> int:
+    """Full setup verification (legacy `cortex-doctor` behaviour)."""
     checks = [c() for c in CHECKS]
     width = max(len(c.name) for c in checks) + 2