diff --git a/.claude-plugin/marketplace.json b/.claude-plugin/marketplace.json
index d39da8d..f441b5e 100644
--- a/.claude-plugin/marketplace.json
+++ b/.claude-plugin/marketplace.json
@@ -5,7 +5,7 @@
     "url": "https://github.com/ShaheerKhawaja"
   },
   "metadata": {
-    "description": "ProductionOS — AI engineering OS for Claude Code and Codex. 80 agents, 41 commands, 17 hooks.",
+    "description": "ProductionOS — AI engineering OS for Claude Code and Codex. 80 agents, 41 commands, 18 hooks.",
     "version": "1.2.0-beta.1",
     "homepage": "https://github.com/ShaheerKhawaja/ProductionOS",
     "repository": "https://github.com/ShaheerKhawaja/ProductionOS",
@@ -15,7 +15,7 @@
     {
       "name": "productionos",
       "source": "./",
-      "description": "Dual-target AI engineering OS — 80 agents, 41 commands, 17 hooks, one shared workflow registry.",
+      "description": "Dual-target AI engineering OS — 80 agents, 41 commands, 18 hooks, one shared workflow registry.",
       "version": "1.2.0-beta.1",
       "author": {
         "name": "Shaheer Khawaja",
diff --git a/.claude-plugin/plugin.json b/.claude-plugin/plugin.json
index 3c65f12..734227e 100644
--- a/.claude-plugin/plugin.json
+++ b/.claude-plugin/plugin.json
@@ -1,6 +1,6 @@
 {
   "name": "productionos",
-  "description": "AI engineering OS for Claude Code and Codex — 80 agents, 41 commands, 17 hooks.",
+  "description": "AI engineering OS for Claude Code and Codex — 80 agents, 41 commands, 18 hooks.",
   "version": "1.2.0-beta.1",
   "author": {
     "name": "Shaheer Khawaja",
diff --git a/.claude/skills/productionos/SKILL.md b/.claude/skills/productionos/SKILL.md
index 40d4db0..79873fb 100644
--- a/.claude/skills/productionos/SKILL.md
+++ b/.claude/skills/productionos/SKILL.md
@@ -23,7 +23,7 @@ metadata:
 
 # ProductionOS
 
-ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 17 hooks.
+ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 18 hooks.
 
 Use this skill to translate the Claude-oriented workflow specs in this repo into Codex-native execution.
 
diff --git a/SKILL.md b/SKILL.md
index 701e134..d8bf14d 100644
--- a/SKILL.md
+++ b/SKILL.md
@@ -6,7 +6,7 @@ argument-hint: "[goal, command name, or repo path]"
 
 # ProductionOS
 
-ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 17 hooks.
+ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 18 hooks.
 
 Use this skill to translate the Claude-oriented workflow specs in this repo into Codex-native execution.
 
diff --git a/docs/CODEX-PARITY-HANDOFF.md b/docs/CODEX-PARITY-HANDOFF.md
index 354985c..52340e8 100644
--- a/docs/CODEX-PARITY-HANDOFF.md
+++ b/docs/CODEX-PARITY-HANDOFF.md
@@ -2,7 +2,7 @@
 
 This document is generated from the runtime-neutral registry in [scripts/lib/runtime-targets.ts](../scripts/lib/runtime-targets.ts).
 
-Current snapshot: 80 agents, 41 commands, 17 hooks, 14 templates, 28 tests.
+Current snapshot: 80 agents, 41 commands, 18 hooks, 14 templates, 28 tests.
 
 ## Runtime Targets
 
diff --git a/hooks/README.md b/hooks/README.md
new file mode 100644
index 0000000..79caef2
--- /dev/null
+++ b/hooks/README.md
@@ -0,0 +1,87 @@
+# ProductionOS Hooks
+
+15 lifecycle hooks across 4 events. Auto-enforced via `hooks/hooks.json`. All hooks degrade gracefully if dependencies are missing.
+
+## Hook Inventory
+
+### SessionStart (1 hook)
+
+| Hook | What | Dependencies |
+|------|------|-------------|
+| `session-start.sh` | Init state, display banner, load instincts, context recovery | python3, bun |
+
+### PreToolUse (5 hooks)
+
+| Hook | Matcher | What | Dependencies |
+|------|---------|------|-------------|
+| `scope-enforcement.sh` | Edit/Write/Bash | Block out-of-scope file edits | python3, jq |
+| `repo-boundary-guard.sh` | Edit/Write/Bash | Block cross-repo operations | python3, jq |
+| `protected-file-guard.sh` | Edit/Write/Bash | Block writes to .env, keys, certs | python3, jq |
+| `pre-edit-security.sh` | Edit/Write/Bash | Advisory on auth/payment file edits | python3, jq |
+| `pre-commit-gitleaks.sh` | Bash | Secret detection in git commits | python3, jq, gitleaks (optional) |
+
+### PostToolUse (4 hooks)
+
+| Hook | Matcher | What | Dependencies |
+|------|---------|------|-------------|
+| `self-learn.sh` | Edit/Write | Cross-session pattern capture | python3, jq |
+| `post-edit-telemetry.sh` | Edit/Write | Log file edits to analytics | python3, jq |
+| `post-edit-review-hint.sh` | Edit/Write | Suggest review after 10+ edits | python3 |
+| `eval-gate.sh` | Edit/Write | Quality gate (tests + tsc + eval) | bun, jq |
+
+### Stop (3 hooks)
+
+| Hook | What | Dependencies |
+|------|------|-------------|
+| `stop-session-handoff.sh` | Generate session summary + Obsidian log | python3, jq |
+| `stop-extract-instincts.sh` | Extract patterns to instincts directory | python3 |
+| `stop-eval-gate.sh` | Session-end evaluation score | bun |
+
+### Non-Lifecycle (1 hook)
+
+| Hook | What |
+|------|------|
+| `pre-push-gate.sh` | Git pre-push validation (tests + tsc) |
+
+## Error Handling
+
+All hooks include:
+- `set -euo pipefail` for strict error handling
+- Binary availability checks (`_HAS_BUN`, `_HAS_PYTHON`, `_HAS_JQ`)
+- `_log_error()` function writing to `~/.productionos/logs/hook-errors.log`
+- Graceful degradation when dependencies are missing (skip, don't crash)
+
+## Error Log
+
+Hook failures are logged to:
+```
+~/.productionos/logs/hook-errors.log
+```
+
+Format: `[ISO8601] ERROR hook-name.sh: description`
+
+## Configuration
+
+Hooks are registered in `hooks/hooks.json`. The file is read by Claude Code on session start.
+
+### Disable a Specific Hook
+
+Remove the hook entry from `hooks/hooks.json`. Do not delete the `.sh` file.
+
+### Disable All Hooks
+
+Remove the `hooks` key from `hooks/hooks.json` or rename the file.
+
+### Eval-Gate Frequency
+
+The eval-gate runs tests after every 10 edits (configurable):
+- Fast gate (tests + tsc): every 10 edits
+- Full eval: every 20 edits
+
+## Adding a New Hook
+
+1. Create `hooks/my-hook.sh` with `#!/usr/bin/env bash` + `set -euo pipefail`
+2. Include the binary check preamble (copy from any existing hook)
+3. Add entry to `hooks/hooks.json` under the appropriate event
+4. Make executable: `chmod +x hooks/my-hook.sh`
+5. Test: `echo '{}' | bash hooks/my-hook.sh`
diff --git a/hooks/eval-gate.sh b/hooks/eval-gate.sh
index 32217c8..4c67e04 100755
--- a/hooks/eval-gate.sh
+++ b/hooks/eval-gate.sh
@@ -4,6 +4,18 @@
 # Enforces 8/10 quality standard — blocks session completion if below threshold.
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
 EDIT_COUNT_FILE="$STATE_DIR/sessions/edit-count-$$"
@@ -38,7 +50,12 @@ if [ "$CURRENT_COUNT" -gt 0 ] && [ $((CURRENT_COUNT % EVAL_INTERVAL)) -eq 0 ]; t
   fi
 
   # Run full eval (slower, only at 20+ edits)
-  if [ "$CURRENT_COUNT" -ge 20 ]; then
+  if [ "$CURRENT_COUNT" -ge 20 ] && [ "$_HAS_BUN" = "1" ]; then
+    # Verify eval script exists before running
+    if [ ! -f "$PLUGIN_ROOT/scripts/eval-runner.ts" ] && [ ! -f "$PLUGIN_ROOT/package.json" ]; then
+      _log_error "eval-runner.ts not found, skipping full eval"
+      exit 0
+    fi
     EVAL_SCORE=$(bun run eval 2>&1 | grep "OVERALL" | grep -oE '[0-9]+\.[0-9]+' || echo "0")
     # Validate EVAL_SCORE is a plain decimal number before use
     if [[ "$EVAL_SCORE" =~ ^[0-9]+\.[0-9]+$ ]]; then
diff --git a/hooks/post-bash-telemetry.sh b/hooks/post-bash-telemetry.sh
index 78aca8a..4535399 100755
--- a/hooks/post-bash-telemetry.sh
+++ b/hooks/post-bash-telemetry.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS PostToolUse — log bash command telemetry
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
diff --git a/hooks/post-edit-review-hint.sh b/hooks/post-edit-review-hint.sh
index cc8ce52..42b00df 100755
--- a/hooks/post-edit-review-hint.sh
+++ b/hooks/post-edit-review-hint.sh
@@ -2,6 +2,18 @@
 # ProductionOS PostToolUse — auto code review hint after edits
 # Tracks edit count per session. After 10+ edits, suggests running review.
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
diff --git a/hooks/post-edit-telemetry.sh b/hooks/post-edit-telemetry.sh
index 96c9e71..e7a017c 100755
--- a/hooks/post-edit-telemetry.sh
+++ b/hooks/post-edit-telemetry.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS PostToolUse — log edit telemetry (project-scoped)
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
diff --git a/hooks/pre-commit-gitleaks.sh b/hooks/pre-commit-gitleaks.sh
index 5d1bc05..dd613e6 100755
--- a/hooks/pre-commit-gitleaks.sh
+++ b/hooks/pre-commit-gitleaks.sh
@@ -4,6 +4,18 @@
 # Only triggers on Bash tool invocations containing 'git commit'
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
 INPUT=$(cat)
 
diff --git a/hooks/pre-edit-security.sh b/hooks/pre-edit-security.sh
index a35c7e6..8cb7b76 100755
--- a/hooks/pre-edit-security.sh
+++ b/hooks/pre-edit-security.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS PreToolUse — security advisory on sensitive file edits
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 
diff --git a/hooks/pre-push-gate.sh b/hooks/pre-push-gate.sh
index dcd23c4..5addf62 100755
--- a/hooks/pre-push-gate.sh
+++ b/hooks/pre-push-gate.sh
@@ -4,6 +4,18 @@
 # Also called by the Stop hook for session-end validation.
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 # Handle being called from .git/hooks/ (symlink target)
 if [ ! -f "$PLUGIN_ROOT/package.json" ]; then
diff --git a/hooks/protected-file-guard.sh b/hooks/protected-file-guard.sh
index edcb391..6a49f8f 100755
--- a/hooks/protected-file-guard.sh
+++ b/hooks/protected-file-guard.sh
@@ -3,6 +3,18 @@
 # Returns JSON: {"decision":"block","reason":"..."} or {"decision":"allow"}
 # Handles Edit, Write, AND Bash tools (detects file writes in shell commands)
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 
diff --git a/hooks/repo-boundary-guard.sh b/hooks/repo-boundary-guard.sh
index b96ede4..53c9379 100755
--- a/hooks/repo-boundary-guard.sh
+++ b/hooks/repo-boundary-guard.sh
@@ -7,6 +7,18 @@
 # - No active project detected → ALLOW everything
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
 INPUT=$(cat)
 
diff --git a/hooks/scope-enforcement.sh b/hooks/scope-enforcement.sh
index 5ed7afa..3e24d7c 100755
--- a/hooks/scope-enforcement.sh
+++ b/hooks/scope-enforcement.sh
@@ -7,6 +7,18 @@
 # GAP-22 (git apply/am)
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 # ─── Fast Exit: No scope enforcement active ─────────────────
 SCOPE_FILE="${PRODUCTIONOS_AGENT_SCOPE:-}"
 if [ -z "$SCOPE_FILE" ] || [ ! -f "$SCOPE_FILE" ]; then
diff --git a/hooks/self-learn.sh b/hooks/self-learn.sh
index 7e2b4c2..fa4cac8 100755
--- a/hooks/self-learn.sh
+++ b/hooks/self-learn.sh
@@ -5,6 +5,18 @@
 # v2: Cross-session pattern aggregation
 
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 
diff --git a/hooks/session-start.sh b/hooks/session-start.sh
index d5d0d72..155235f 100755
--- a/hooks/session-start.sh
+++ b/hooks/session-start.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS session start — init state, track session, detect project, show status
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
diff --git a/hooks/stop-eval-gate.sh b/hooks/stop-eval-gate.sh
index fc8b65c..1c6a548 100755
--- a/hooks/stop-eval-gate.sh
+++ b/hooks/stop-eval-gate.sh
@@ -3,6 +3,18 @@
 # Enforces 10/10 standard by writing warnings to handoff document.
 set -euo pipefail
 
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
+
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${HOME}/.productionos"
 
diff --git a/hooks/stop-extract-instincts.sh b/hooks/stop-extract-instincts.sh
index 9bd75e7..aaac3ef 100755
--- a/hooks/stop-extract-instincts.sh
+++ b/hooks/stop-extract-instincts.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS Stop hook — extract instincts from session analytics
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 # Resolve plugin root — works for both marketplace install and git clone
 PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "$0")/.." && pwd)}"
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
diff --git a/hooks/stop-session-handoff.sh b/hooks/stop-session-handoff.sh
index f9ba90b..ba8452a 100755
--- a/hooks/stop-session-handoff.sh
+++ b/hooks/stop-session-handoff.sh
@@ -1,6 +1,18 @@
 #!/usr/bin/env bash
 # ProductionOS Stop hook — session cleanup, project-scoped handoff, mini-retro, instinct extraction
 set -euo pipefail
+
+# === Binary availability (degrade gracefully if missing) ===
+_HAS_BUN=$(command -v bun >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_PYTHON=$(command -v python3 >/dev/null 2>&1 && echo "1" || echo "0")
+_HAS_JQ=$(command -v jq >/dev/null 2>&1 && echo "1" || echo "0")
+_LOG_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}/logs"
+mkdir -p "$_LOG_DIR" 2>/dev/null || true
+
+_log_error() {
+  local msg="$1"
+  echo "[$(date -u +%Y-%m-%dT%H:%M:%SZ)] ERROR $(basename "$0"): $msg" >> "$_LOG_DIR/hook-errors.log" 2>/dev/null || true
+}
 STATE_DIR="${PRODUCTIONOS_HOME:-$HOME/.productionos}"
 
 # Read active project before cleanup
diff --git a/skills/productionos/SKILL.md b/skills/productionos/SKILL.md
index 701e134..d8bf14d 100644
--- a/skills/productionos/SKILL.md
+++ b/skills/productionos/SKILL.md
@@ -6,7 +6,7 @@ argument-hint: "[goal, command name, or repo path]"
 
 # ProductionOS
 
-ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 17 hooks.
+ProductionOS is a dual-target AI engineering operating system with 80 agents, 41 commands, and 18 hooks.
 
 Use this skill to translate the Claude-oriented workflow specs in this repo into Codex-native execution.