diff --git a/05-troubleshooting/claude-mem-setting-sources-empty-arg.md b/05-troubleshooting/claude-mem-setting-sources-empty-arg.md
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+---
+title: "claude-mem Silently Fails with Claude Code 2.1+ (Empty --setting-sources)"
+domain: troubleshooting
+category: claude-code
+tags: [claude-code, claude-mem, cli, subprocess, version-mismatch, shim]
+status: published
+created: 2026-04-17
+updated: 2026-04-17
+---
+
+# claude-mem Silently Fails with Claude Code 2.1+ (Empty `--setting-sources`)
+
+## Symptom
+
+After installing the `claude-mem` plugin (v12.1.3) in Claude Code (v2.1.112), every Claude Code session starts with:
+
+```
+No previous sessions found for this project yet.
+```
+
+…even for directories where you've worked repeatedly. Session records *do* appear in `~/.claude-mem/claude-mem.db` (table `sdk_sessions`), but:
+
+- `session_summaries` count stays at **0**
+- `observations` count stays at **0**
+- Chroma vector DB stays empty
+
+Tailing `~/.claude-mem/logs/claude-mem-YYYY-MM-DD.log` shows the Stop hook firing on every assistant turn, but always:
+
+```
+[HOOK  ] → Stop: Requesting summary {hasLastAssistantMessage=true}
+[HOOK  ] Summary processing complete {waitedMs=503, summaryStored=null}
+```
+
+No errors, no stack traces — just a silent `null`. Raising `CLAUDE_MEM_LOG_LEVEL` to `DEBUG` reveals the true error:
+
+```
+[WARN ] [SDK_SPAWN] Claude process exited {code=1, signal=null, pid=…}
+[ERROR] [SESSION] Generator failed {provider=claude, error=Claude Code process exited with code 1}
+```
+
+## Root cause
+
+`claude-mem` 12.1.3 spawns the `claude` CLI as a subprocess to generate per-turn observations and session summaries. The argv it passes includes:
+
+```
+claude --output-format stream-json --verbose --input-format stream-json \
+       --model claude-sonnet-4-6 \
+       --disallowedTools Bash,Read,Write,… \
+       --setting-sources \               ← no value!
+       --permission-mode default
+```
+
+`claude-mem` intends to pass `--setting-sources ""` (empty string, meaning "no sources"). Claude Code **v2.1.x** now validates this flag and rejects empty values — it requires one of `user`, `project`, or `local`. With no value present, the CLI's argument parser consumes the next flag (`--permission-mode`) as the value and produces:
+
+```
+Error processing --setting-sources: Invalid setting source: --permission-mode.
+Valid options are: user, project, local
+```
+
+The child process exits immediately with code 1 (within ~130 ms). `claude-mem` only logs `exited with code 1` and discards stderr by default, which is why the failure looks silent.
+
+This is a **version-mismatch bug** between `claude-mem` 12.1.3 (latest as of 2026-04-17) and `claude-code` 2.1.x. Earlier Claude Code releases accepted empty values.
+
+## Investigation path
+
+1. Confirm worker processes are alive:
+   ```bash
+   pgrep -fl "worker-service|mcp-server.cjs|chroma-mcp"
+   cat ~/.claude-mem/supervisor.json
+   ```
+2. Confirm sessions are being *recorded* but not *summarised*:
+   ```bash
+   sqlite3 ~/.claude-mem/claude-mem.db \
+     "SELECT COUNT(*) FROM sdk_sessions;  -- nonzero
+      SELECT COUNT(*) FROM session_summaries;  -- 0 = pipeline broken
+      SELECT COUNT(*) FROM observations;       -- 0 = pipeline broken"
+   ```
+3. Grep the log for `summaryStored=null` — if every Stop hook ends in `null`, summarisation is failing.
+4. Raise log level to expose the real error:
+   ```bash
+   # In ~/.claude-mem/settings.json
+   "CLAUDE_MEM_LOG_LEVEL": "DEBUG"
+   ```
+   Kill and respawn workers (`pkill -f worker-service.cjs`). New logs should show `SDK_SPAWN Claude process exited {code=1}`.
+5. Capture the exact argv by replacing `CLAUDE_CODE_PATH` with a debug shim that logs `$@` before exec'ing the real binary (see the fix below for the production shim — the debug version just tees argv to a log file).
+
+## The fix
+
+Apply in this order.
+
+### 1. Fix the settings `claude-mem` ships with empty
+
+Edit `~/.claude-mem/settings.json`:
+
+```json
+{
+  "CLAUDE_CODE_PATH": "/Users/you/.local/bin/claude-shim",
+  "CLAUDE_MEM_TIER_SUMMARY_MODEL": "claude-sonnet-4-6"
+}
+```
+
+Both ship empty in a fresh install. `CLAUDE_CODE_PATH` points at the shim (below), not the real binary. `CLAUDE_MEM_TIER_SUMMARY_MODEL` is required when `CLAUDE_MEM_TIER_ROUTING_ENABLED=true`.
+
+### 2. Install the shim
+
+`/Users/you/.local/bin/claude-shim`:
+
+```bash
+#!/bin/bash
+# Workaround shim for claude-mem 12.1.3 <-> Claude Code 2.1.x incompat.
+# claude-mem passes `--setting-sources` with no value; Claude CLI 2.1+ rejects
+# empty and consumes the next flag as the value. Fix: inject "user" when missing.
+
+REAL=/Users/you/.local/bin/claude
+
+new_args=()
+i=0
+args=("$@")
+while [ $i -lt ${#args[@]} ]; do
+  cur="${args[$i]}"
+  new_args+=("$cur")
+  if [ "$cur" = "--setting-sources" ]; then
+    next="${args[$((i+1))]}"
+    case "$next" in
+      user|project|local) : ;;   # already valid
+      *) new_args+=("user") ;;   # inject missing value
+    esac
+  fi
+  i=$((i+1))
+done
+
+exec "$REAL" "${new_args[@]}"
+```
+
+Chmod it executable: `chmod +x ~/.local/bin/claude-shim`.
+
+### 3. Restart workers
+
+```bash
+pkill -f "worker-service.cjs --daemon"
+```
+
+They respawn automatically on the next Claude Code hook fire. Verify:
+
+```bash
+# Within ~15 s:
+sqlite3 ~/.claude-mem/claude-mem.db "SELECT COUNT(*) FROM observations;"
+# Should be growing as you continue the session.
+```
+
+### 4. Sanity-check the shim is being used
+
+```bash
+ps -eww | grep -F 'setting-sources user'
+```
+
+Every live `claude` child should have `--setting-sources user` in its argv, not a bare `--setting-sources`.
+
+## Why a shim instead of patching `claude-mem`
+
+The offending code is inside the minified `worker-service.cjs` bundle shipped by `@anthropic-ai/claude-code` SDK, which `claude-mem` vendors. Patching the bundle is possible but fragile: any `claude-mem` update overwrites it. The shim is a one-file wrapper at a stable path, survives plugin updates, and becomes a no-op the moment upstream ships a fix.
+
+## When to remove the shim
+
+Check for a newer `claude-mem` release or an Anthropic SDK update that stops passing `--setting-sources` with an empty value. Test by:
+
+1. Point `CLAUDE_CODE_PATH` back at the real `/Users/you/.local/bin/claude`.
+2. Restart workers.
+3. Confirm `observations` count keeps growing.
+
+If it does, remove the shim. If not, restore the shim path and wait for a later release.
+
+## Related
+
+- Install notes: `20-Projects/Personal-Tasks.md` — "Install claude-mem plugin on MajorMac — 2026-04-15"
+- Config file: `~/.claude-mem/settings.json`
+- Logs: `~/.claude-mem/logs/claude-mem-YYYY-MM-DD.log`
+- DB: `~/.claude-mem/claude-mem.db` (SQLite, FTS5 enabled)
diff --git a/05-troubleshooting/index.md b/05-troubleshooting/index.md
index 1e3b9f5..99c323e 100644
--- a/05-troubleshooting/index.md
+++ b/05-troubleshooting/index.md
@@ -1,6 +1,6 @@
 ---
 created: 2026-03-15T06:37
-updated: 2026-04-13T10:10
+updated: 2026-04-17T09:57
 ---
 # 🔧 General Troubleshooting
 
@@ -44,3 +44,4 @@ Practical fixes for common Linux, networking, and application problems.
 ## 🤖 AI / Local LLM
 - [Ollama Drops Off Tailscale When Mac Sleeps](ollama-macos-sleep-tailscale-disconnect.md)
 - [Windows OpenSSH Server (sshd) Stops After Reboot](networking/windows-sshd-stops-after-reboot.md)
+- [claude-mem Silently Fails with Claude Code 2.1+ (Empty `--setting-sources`)](claude-mem-setting-sources-empty-arg.md)