diff --git a/hooks/hooks.json b/hooks/hooks.json
index cdd2584d..22799c08 100644
--- a/hooks/hooks.json
+++ b/hooks/hooks.json
@@ -126,6 +126,30 @@
         ],
         "description": "Check MCP server health before MCP tool execution and block unhealthy MCP calls",
         "id": "pre:mcp-health-check"
+      },
+      {
+        "matcher": "Edit|Write|MultiEdit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/hooks/run-with-flags.js\" \"pre:edit-write:gateguard-fact-force\" \"scripts/hooks/gateguard-fact-force.js\" \"standard,strict\"",
+            "timeout": 5
+          }
+        ],
+        "description": "Fact-forcing gate: block first Edit/Write/MultiEdit per file and demand investigation (importers, data schemas, user instruction) before allowing",
+        "id": "pre:edit-write:gateguard-fact-force"
+      },
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/hooks/run-with-flags.js\" \"pre:bash:gateguard-fact-force\" \"scripts/hooks/gateguard-fact-force.js\" \"standard,strict\"",
+            "timeout": 5
+          }
+        ],
+        "description": "Fact-forcing gate: block destructive Bash commands and demand rollback plan; quote user instruction on first Bash per session",
+        "id": "pre:bash:gateguard-fact-force"
       }
     ],
     "PreCompact": [
diff --git a/scripts/hooks/gateguard-fact-force.js b/scripts/hooks/gateguard-fact-force.js
new file mode 100644
index 00000000..b8a0fcc8
--- /dev/null
+++ b/scripts/hooks/gateguard-fact-force.js
@@ -0,0 +1,265 @@
+#!/usr/bin/env node
+/**
+ * PreToolUse Hook: GateGuard Fact-Forcing Gate
+ *
+ * Forces Claude to investigate before editing files or running commands.
+ * Instead of asking "are you sure?" (which LLMs always answer "yes"),
+ * this hook demands concrete facts: importers, public API, data schemas.
+ *
+ * The act of investigation creates awareness that self-evaluation never did.
+ *
+ * Gates:
+ *   - Edit/Write: list importers, affected API, verify data schemas, quote instruction
+ *   - Bash (destructive): list targets, rollback plan, quote instruction
+ *   - Bash (routine): quote current instruction (once per session)
+ *
+ * Compatible with run-with-flags.js via module.exports.run().
+ * Cross-platform (Windows, macOS, Linux).
+ *
+ * Full package with config support: pip install gateguard-ai
+ * Repo: https://github.com/zunoworks/gateguard
+ */
+
+'use strict';
+
+const crypto = require('crypto');
+const fs = require('fs');
+const path = require('path');
+
+// Session state — scoped per session to avoid cross-session races.
+// Uses CLAUDE_SESSION_ID (set by Claude Code) or falls back to PID-based isolation.
+const STATE_DIR = process.env.GATEGUARD_STATE_DIR || path.join(process.env.HOME || process.env.USERPROFILE || '/tmp', '.gateguard');
+const SESSION_ID = process.env.CLAUDE_SESSION_ID || process.env.ECC_SESSION_ID || `pid-${process.ppid || process.pid}`;
+const STATE_FILE = path.join(STATE_DIR, `state-${SESSION_ID.replace(/[^a-zA-Z0-9_-]/g, '_')}.json`);
+
+// State expires after 30 minutes of inactivity
+const SESSION_TIMEOUT_MS = 30 * 60 * 1000;
+
+// Maximum checked entries to prevent unbounded growth
+const MAX_CHECKED_ENTRIES = 500;
+const MAX_SESSION_KEYS = 50;
+const ROUTINE_BASH_SESSION_KEY = '__bash_session__';
+
+const DESTRUCTIVE_BASH = /\b(rm\s+-rf|git\s+reset\s+--hard|git\s+checkout\s+--|git\s+clean\s+-f|drop\s+table|delete\s+from|truncate|git\s+push\s+--force|dd\s+if=)\b/i;
+
+// --- State management (per-session, atomic writes, bounded) ---
+
+function loadState() {
+  try {
+    if (fs.existsSync(STATE_FILE)) {
+      const state = JSON.parse(fs.readFileSync(STATE_FILE, 'utf8'));
+      const lastActive = state.last_active || 0;
+      if (Date.now() - lastActive > SESSION_TIMEOUT_MS) {
+        try { fs.unlinkSync(STATE_FILE); } catch (_) { /* ignore */ }
+        return { checked: [], last_active: Date.now() };
+      }
+      return state;
+    }
+  } catch (_) { /* ignore */ }
+  return { checked: [], last_active: Date.now() };
+}
+
+function pruneCheckedEntries(checked) {
+  if (checked.length <= MAX_CHECKED_ENTRIES) {
+    return checked;
+  }
+
+  const preserved = checked.includes(ROUTINE_BASH_SESSION_KEY) ? [ROUTINE_BASH_SESSION_KEY] : [];
+  const sessionKeys = checked.filter(k => k.startsWith('__') && k !== ROUTINE_BASH_SESSION_KEY);
+  const fileKeys = checked.filter(k => !k.startsWith('__'));
+  const remainingSessionSlots = Math.max(MAX_SESSION_KEYS - preserved.length, 0);
+  const cappedSession = sessionKeys.slice(-remainingSessionSlots);
+  const remainingFileSlots = Math.max(MAX_CHECKED_ENTRIES - preserved.length - cappedSession.length, 0);
+  const cappedFiles = fileKeys.slice(-remainingFileSlots);
+  return [...preserved, ...cappedSession, ...cappedFiles];
+}
+
+function saveState(state) {
+  try {
+    state.last_active = Date.now();
+    state.checked = pruneCheckedEntries(state.checked);
+    fs.mkdirSync(STATE_DIR, { recursive: true });
+    // Atomic write: temp file + rename prevents partial reads
+    const tmpFile = STATE_FILE + '.tmp.' + process.pid;
+    fs.writeFileSync(tmpFile, JSON.stringify(state, null, 2), 'utf8');
+    fs.renameSync(tmpFile, STATE_FILE);
+  } catch (_) { /* ignore */ }
+}
+
+function markChecked(key) {
+  const state = loadState();
+  if (!state.checked.includes(key)) {
+    state.checked.push(key);
+    saveState(state);
+  }
+}
+
+function isChecked(key) {
+  const state = loadState();
+  const found = state.checked.includes(key);
+  saveState(state);
+  return found;
+}
+
+// Prune stale session files older than 1 hour
+(function pruneStaleFiles() {
+  try {
+    const files = fs.readdirSync(STATE_DIR);
+    const now = Date.now();
+    for (const f of files) {
+      if (!f.startsWith('state-') || !f.endsWith('.json')) continue;
+      const fp = path.join(STATE_DIR, f);
+      const stat = fs.statSync(fp);
+      if (now - stat.mtimeMs > SESSION_TIMEOUT_MS * 2) {
+        fs.unlinkSync(fp);
+      }
+    }
+  } catch (_) { /* ignore */ }
+})();
+
+// --- Sanitize file path against injection ---
+
+function sanitizePath(filePath) {
+  // Strip control chars (including null), bidi overrides, and newlines
+  return filePath.replace(/[\x00-\x1f\x7f\u200e\u200f\u202a-\u202e\u2066-\u2069]/g, ' ').trim().slice(0, 500);
+}
+
+// --- Gate messages ---
+
+function editGateMsg(filePath) {
+  const safe = sanitizePath(filePath);
+  return [
+    '[Fact-Forcing Gate]',
+    '',
+    `Before editing ${safe}, present these facts:`,
+    '',
+    '1. List ALL files that import/require this file (use Grep)',
+    '2. List the public functions/classes affected by this change',
+    '3. If this file reads/writes data files, show field names, structure, and date format (use redacted or synthetic values, not raw production data)',
+    '4. Quote the user\'s current instruction verbatim',
+    '',
+    'Present the facts, then retry the same operation.'
+  ].join('\n');
+}
+
+function writeGateMsg(filePath) {
+  const safe = sanitizePath(filePath);
+  return [
+    '[Fact-Forcing Gate]',
+    '',
+    `Before creating ${safe}, present these facts:`,
+    '',
+    '1. Name the file(s) and line(s) that will call this new file',
+    '2. Confirm no existing file serves the same purpose (use Glob)',
+    '3. If this file reads/writes data files, show field names, structure, and date format (use redacted or synthetic values, not raw production data)',
+    '4. Quote the user\'s current instruction verbatim',
+    '',
+    'Present the facts, then retry the same operation.'
+  ].join('\n');
+}
+
+function destructiveBashMsg() {
+  return [
+    '[Fact-Forcing Gate]',
+    '',
+    'Destructive command detected. Before running, present:',
+    '',
+    '1. List all files/data this command will modify or delete',
+    '2. Write a one-line rollback procedure',
+    '3. Quote the user\'s current instruction verbatim',
+    '',
+    'Present the facts, then retry the same operation.'
+  ].join('\n');
+}
+
+function routineBashMsg() {
+  return [
+    '[Fact-Forcing Gate]',
+    '',
+    'Quote the user\'s current instruction verbatim.',
+    'Then retry the same operation.'
+  ].join('\n');
+}
+
+// --- Deny helper ---
+
+function denyResult(reason) {
+  return {
+    stdout: JSON.stringify({
+      hookSpecificOutput: {
+        hookEventName: 'PreToolUse',
+        permissionDecision: 'deny',
+        permissionDecisionReason: reason
+      }
+    }),
+    exitCode: 0
+  };
+}
+
+// --- Core logic (exported for run-with-flags.js) ---
+
+function run(rawInput) {
+  let data;
+  try {
+    data = typeof rawInput === 'string' ? JSON.parse(rawInput) : rawInput;
+  } catch (_) {
+    return rawInput; // allow on parse error
+  }
+
+  const rawToolName = data.tool_name || '';
+  const toolInput = data.tool_input || {};
+  // Normalize: case-insensitive matching via lookup map
+  const TOOL_MAP = { 'edit': 'Edit', 'write': 'Write', 'multiedit': 'MultiEdit', 'bash': 'Bash' };
+  const toolName = TOOL_MAP[rawToolName.toLowerCase()] || rawToolName;
+
+  if (toolName === 'Edit' || toolName === 'Write') {
+    const filePath = toolInput.file_path || '';
+    if (!filePath) {
+      return rawInput; // allow
+    }
+
+    if (!isChecked(filePath)) {
+      markChecked(filePath);
+      return denyResult(toolName === 'Edit' ? editGateMsg(filePath) : writeGateMsg(filePath));
+    }
+
+    return rawInput; // allow
+  }
+
+  if (toolName === 'MultiEdit') {
+    const edits = toolInput.edits || [];
+    for (const edit of edits) {
+      const filePath = edit.file_path || '';
+      if (filePath && !isChecked(filePath)) {
+        markChecked(filePath);
+        return denyResult(editGateMsg(filePath));
+      }
+    }
+    return rawInput; // allow
+  }
+
+  if (toolName === 'Bash') {
+    const command = toolInput.command || '';
+
+    if (DESTRUCTIVE_BASH.test(command)) {
+      // Gate destructive commands on first attempt; allow retry after facts presented
+      const key = '__destructive__' + crypto.createHash('sha256').update(command).digest('hex').slice(0, 16);
+      if (!isChecked(key)) {
+        markChecked(key);
+        return denyResult(destructiveBashMsg());
+      }
+      return rawInput; // allow retry after facts presented
+    }
+
+    if (!isChecked(ROUTINE_BASH_SESSION_KEY)) {
+      markChecked(ROUTINE_BASH_SESSION_KEY);
+      return denyResult(routineBashMsg());
+    }
+
+    return rawInput; // allow
+  }
+
+  return rawInput; // allow
+}
+
+module.exports = { run };
diff --git a/skills/gateguard/SKILL.md b/skills/gateguard/SKILL.md
new file mode 100644
index 00000000..e6c69a4f
--- /dev/null
+++ b/skills/gateguard/SKILL.md
@@ -0,0 +1,120 @@
+---
+name: gateguard
+description: Fact-forcing gate that blocks Edit/Write/Bash (including MultiEdit) and demands concrete investigation (importers, data schemas, user instruction) before allowing the action. Measurably improves output quality by +2.25 points vs ungated agents.
+origin: community
+---
+
+# GateGuard — Fact-Forcing Pre-Action Gate
+
+A PreToolUse hook that forces Claude to investigate before editing. Instead of self-evaluation ("are you sure?"), it demands concrete facts. The act of investigation creates awareness that self-evaluation never did.
+
+## When to Activate
+
+- Working on any codebase where file edits affect multiple modules
+- Projects with data files that have specific schemas or date formats
+- Teams where AI-generated code must match existing patterns
+- Any workflow where Claude tends to guess instead of investigating
+
+## Core Concept
+
+LLM self-evaluation doesn't work. Ask "did you violate any policies?" and the answer is always "no." This is verified experimentally.
+
+But asking "list every file that imports this module" forces the LLM to run Grep and Read. The investigation itself creates context that changes the output.
+
+**Three-stage gate:**
+
+```
+1. DENY  — block the first Edit/Write/Bash attempt
+2. FORCE — tell the model exactly which facts to gather
+3. ALLOW — permit retry after facts are presented
+```
+
+No competitor does all three. Most stop at deny.
+
+## Evidence
+
+Two independent A/B tests, identical agents, same task:
+
+| Task | Gated | Ungated | Gap |
+| --- | --- | --- | --- |
+| Analytics module | 8.0/10 | 6.5/10 | +1.5 |
+| Webhook validator | 10.0/10 | 7.0/10 | +3.0 |
+| **Average** | **9.0** | **6.75** | **+2.25** |
+
+Both agents produce code that runs and passes tests. The difference is design depth.
+
+## Gate Types
+
+### Edit / MultiEdit Gate (first edit per file)
+
+MultiEdit is handled identically — each file in the batch is gated individually.
+
+```
+Before editing {file_path}, present these facts:
+
+1. List ALL files that import/require this file (use Grep)
+2. List the public functions/classes affected by this change
+3. If this file reads/writes data files, show field names, structure,
+   and date format (use redacted or synthetic values, not raw production data)
+4. Quote the user's current instruction verbatim
+```
+
+### Write Gate (first new file creation)
+
+```
+Before creating {file_path}, present these facts:
+
+1. Name the file(s) and line(s) that will call this new file
+2. Confirm no existing file serves the same purpose (use Glob)
+3. If this file reads/writes data files, show field names, structure,
+   and date format (use redacted or synthetic values, not raw production data)
+4. Quote the user's current instruction verbatim
+```
+
+### Destructive Bash Gate (every destructive command)
+
+Triggers on: `rm -rf`, `git reset --hard`, `git push --force`, `drop table`, etc.
+
+```
+1. List all files/data this command will modify or delete
+2. Write a one-line rollback procedure
+3. Quote the user's current instruction verbatim
+```
+
+### Routine Bash Gate (once per session)
+
+```
+Quote the user's current instruction verbatim.
+```
+
+## Quick Start
+
+### Option A: Use the ECC hook (zero install)
+
+The hook at `scripts/hooks/gateguard-fact-force.js` is included in this plugin. Enable it via hooks.json.
+
+### Option B: Full package with config
+
+```bash
+pip install gateguard-ai
+gateguard init
+```
+
+This adds `.gateguard.yml` for per-project configuration (custom messages, ignore paths, gate toggles).
+
+## Anti-Patterns
+
+- **Don't use self-evaluation instead.** "Are you sure?" always gets "yes." This is experimentally verified.
+- **Don't skip the data schema check.** Both A/B test agents assumed ISO-8601 dates when real data used `%Y/%m/%d %H:%M`. Checking data structure (with redacted values) prevents this entire class of bugs.
+- **Don't gate every single Bash command.** Routine bash gates once per session. Destructive bash gates every time. This balance avoids slowdown while catching real risks.
+
+## Best Practices
+
+- Let the gate fire naturally. Don't try to pre-answer the gate questions — the investigation itself is what improves quality.
+- Customize gate messages for your domain. If your project has specific conventions, add them to the gate prompts.
+- Use `.gateguard.yml` to ignore paths like `.venv/`, `node_modules/`, `.git/`.
+
+## Related Skills
+
+- `safety-guard` — Runtime safety checks (complementary, not overlapping)
+- `code-reviewer` — Post-edit review (GateGuard is pre-edit investigation)
diff --git a/tests/hooks/gateguard-fact-force.test.js b/tests/hooks/gateguard-fact-force.test.js
new file mode 100644
index 00000000..2f0837c3
--- /dev/null
+++ b/tests/hooks/gateguard-fact-force.test.js
@@ -0,0 +1,437 @@
+/**
+ * Tests for scripts/hooks/gateguard-fact-force.js via run-with-flags.js
+ */
+
+const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+const { spawnSync } = require('child_process');
+
+const runner = path.join(__dirname, '..', '..', 'scripts', 'hooks', 'run-with-flags.js');
+const externalStateDir = process.env.GATEGUARD_STATE_DIR;
+const tmpRoot = process.env.TMPDIR || process.env.TEMP || process.env.TMP || '/tmp';
+const stateDir = externalStateDir || fs.mkdtempSync(path.join(tmpRoot, 'gateguard-test-'));
+// Use a fixed session ID so test process and spawned hook process share the same state file
+const TEST_SESSION_ID = 'gateguard-test-session';
+const stateFile = path.join(stateDir, `state-${TEST_SESSION_ID}.json`);
+
+function test(name, fn) {
+  try {
+    fn();
+    console.log(`  ✓ ${name}`);
+    return true;
+  } catch (error) {
+    console.log(`  ✗ ${name}`);
+    console.log(`    Error: ${error.message}`);
+    return false;
+  }
+}
+
+function clearState() {
+  try {
+    if (fs.existsSync(stateFile)) {
+      fs.unlinkSync(stateFile);
+    }
+  } catch (err) {
+    console.error(`  [clearState] failed to remove ${stateFile}: ${err.message}`);
+  }
+}
+
+function writeExpiredState() {
+  try {
+    fs.mkdirSync(stateDir, { recursive: true });
+    const expired = {
+      checked: ['some_file.js', '__bash_session__'],
+      last_active: Date.now() - (31 * 60 * 1000) // 31 minutes ago
+    };
+    fs.writeFileSync(stateFile, JSON.stringify(expired), 'utf8');
+  } catch (_) { /* ignore */ }
+}
+
+function writeState(state) {
+  fs.mkdirSync(stateDir, { recursive: true });
+  fs.writeFileSync(stateFile, JSON.stringify(state), 'utf8');
+}
+
+function runHook(input, env = {}) {
+  const rawInput = typeof input === 'string' ? input : JSON.stringify(input);
+  const result = spawnSync('node', [
+    runner,
+    'pre:edit-write:gateguard-fact-force',
+    'scripts/hooks/gateguard-fact-force.js',
+    'standard,strict'
+  ], {
+    input: rawInput,
+    encoding: 'utf8',
+    env: {
+      ...process.env,
+      ECC_HOOK_PROFILE: 'standard',
+      GATEGUARD_STATE_DIR: stateDir,
+      CLAUDE_SESSION_ID: TEST_SESSION_ID,
+      ...env
+    },
+    timeout: 15000,
+    stdio: ['pipe', 'pipe', 'pipe']
+  });
+
+  return {
+    code: Number.isInteger(result.status) ? result.status : 1,
+    stdout: result.stdout || '',
+    stderr: result.stderr || ''
+  };
+}
+
+function runBashHook(input, env = {}) {
+  const rawInput = typeof input === 'string' ? input : JSON.stringify(input);
+  const result = spawnSync('node', [
+    runner,
+    'pre:bash:gateguard-fact-force',
+    'scripts/hooks/gateguard-fact-force.js',
+    'standard,strict'
+  ], {
+    input: rawInput,
+    encoding: 'utf8',
+    env: {
+      ...process.env,
+      ECC_HOOK_PROFILE: 'standard',
+      GATEGUARD_STATE_DIR: stateDir,
+      CLAUDE_SESSION_ID: TEST_SESSION_ID,
+      ...env
+    },
+    timeout: 15000,
+    stdio: ['pipe', 'pipe', 'pipe']
+  });
+
+  return {
+    code: Number.isInteger(result.status) ? result.status : 1,
+    stdout: result.stdout || '',
+    stderr: result.stderr || ''
+  };
+}
+
+function parseOutput(stdout) {
+  try {
+    return JSON.parse(stdout);
+  } catch (_) {
+    return null;
+  }
+}
+
+function runTests() {
+  console.log('\n=== Testing gateguard-fact-force ===\n');
+
+  let passed = 0;
+  let failed = 0;
+
+  // --- Test 1: denies first Edit per file ---
+  clearState();
+  if (test('denies first Edit per file with fact-forcing message', () => {
+    const input = {
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/app.js', old_string: 'foo', new_string: 'bar' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce JSON output');
+    assert.strictEqual(output.hookSpecificOutput.permissionDecision, 'deny');
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('Fact-Forcing Gate'));
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('import/require'));
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('/src/app.js'));
+  })) passed++; else failed++;
+
+  // --- Test 2: allows second Edit on same file ---
+  if (test('allows second Edit on same file (gate already passed)', () => {
+    const input = {
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/app.js', old_string: 'foo', new_string: 'bar' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce valid JSON output');
+    // When allowed, the hook passes through the raw input (no hookSpecificOutput)
+    // OR if hookSpecificOutput exists, it must not be deny
+    if (output.hookSpecificOutput) {
+      assert.notStrictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+        'should not deny second edit on same file');
+    } else {
+      // Pass-through: output matches original input (allow)
+      assert.strictEqual(output.tool_name, 'Edit', 'pass-through should preserve input');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 3: denies first Write per file ---
+  clearState();
+  if (test('denies first Write per file with fact-forcing message', () => {
+    const input = {
+      tool_name: 'Write',
+      tool_input: { file_path: '/src/new-file.js', content: 'console.log("hello")' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce JSON output');
+    assert.strictEqual(output.hookSpecificOutput.permissionDecision, 'deny');
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('creating'));
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('call this new file'));
+  })) passed++; else failed++;
+
+  // --- Test 4: denies destructive Bash, allows retry ---
+  clearState();
+  if (test('denies destructive Bash commands, allows retry after facts presented', () => {
+    const input = {
+      tool_name: 'Bash',
+      tool_input: { command: 'rm -rf /important/data' }
+    };
+
+    // First call: should deny
+    const result1 = runBashHook(input);
+    assert.strictEqual(result1.code, 0, 'first call exit code should be 0');
+    const output1 = parseOutput(result1.stdout);
+    assert.ok(output1, 'first call should produce JSON output');
+    assert.strictEqual(output1.hookSpecificOutput.permissionDecision, 'deny');
+    assert.ok(output1.hookSpecificOutput.permissionDecisionReason.includes('Destructive'));
+    assert.ok(output1.hookSpecificOutput.permissionDecisionReason.includes('rollback'));
+
+    // Second call (retry after facts presented): should allow
+    const result2 = runBashHook(input);
+    assert.strictEqual(result2.code, 0, 'second call exit code should be 0');
+    const output2 = parseOutput(result2.stdout);
+    assert.ok(output2, 'second call should produce valid JSON output');
+    if (output2.hookSpecificOutput) {
+      assert.notStrictEqual(output2.hookSpecificOutput.permissionDecision, 'deny',
+        'should not deny destructive bash retry after facts presented');
+    } else {
+      assert.strictEqual(output2.tool_name, 'Bash', 'pass-through should preserve input');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 5: denies first routine Bash, allows second ---
+  clearState();
+  if (test('denies first routine Bash, allows second', () => {
+    const input = {
+      tool_name: 'Bash',
+      tool_input: { command: 'ls -la' }
+    };
+
+    // First call: should deny
+    const result1 = runBashHook(input);
+    assert.strictEqual(result1.code, 0, 'first call exit code should be 0');
+    const output1 = parseOutput(result1.stdout);
+    assert.ok(output1, 'first call should produce JSON output');
+    assert.strictEqual(output1.hookSpecificOutput.permissionDecision, 'deny');
+
+    // Second call: should allow
+    const result2 = runBashHook(input);
+    assert.strictEqual(result2.code, 0, 'second call exit code should be 0');
+    const output2 = parseOutput(result2.stdout);
+    assert.ok(output2, 'second call should produce valid JSON output');
+    if (output2.hookSpecificOutput) {
+      assert.notStrictEqual(output2.hookSpecificOutput.permissionDecision, 'deny',
+        'should not deny second routine bash');
+    } else {
+      assert.strictEqual(output2.tool_name, 'Bash', 'pass-through should preserve input');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 6: session state resets after timeout ---
+  if (test('session state resets after 30-minute timeout', () => {
+    writeExpiredState();
+    const input = {
+      tool_name: 'Edit',
+      tool_input: { file_path: 'some_file.js', old_string: 'a', new_string: 'b' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce JSON output after expired state');
+    assert.strictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+      'should deny again after session timeout (state was reset)');
+  })) passed++; else failed++;
+
+  // --- Test 7: allows unknown tool names ---
+  clearState();
+  if (test('allows unknown tool names through', () => {
+    const input = {
+      tool_name: 'Read',
+      tool_input: { file_path: '/src/app.js' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce valid JSON output');
+    if (output.hookSpecificOutput) {
+      assert.notStrictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+        'should not deny unknown tool');
+    } else {
+      assert.strictEqual(output.tool_name, 'Read', 'pass-through should preserve input');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 8: sanitizes file paths with newlines ---
+  clearState();
+  if (test('sanitizes file paths containing newlines', () => {
+    const input = {
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/app.js\ninjected content', old_string: 'a', new_string: 'b' }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce JSON output');
+    assert.strictEqual(output.hookSpecificOutput.permissionDecision, 'deny');
+    const reason = output.hookSpecificOutput.permissionDecisionReason;
+    // The file path portion of the reason must not contain any raw newlines
+    // (sanitizePath replaces \n and \r with spaces)
+    const pathLine = reason.split('\n').find(l => l.includes('/src/app.js'));
+    assert.ok(pathLine, 'reason should mention the file path');
+    assert.ok(!pathLine.includes('\n'), 'file path line must not contain raw newlines');
+    assert.ok(!reason.includes('/src/app.js\n'), 'newline after file path should be sanitized');
+    assert.ok(!reason.includes('\ninjected'), 'injected content must not appear on its own line');
+  })) passed++; else failed++;
+
+  // --- Test 9: respects ECC_DISABLED_HOOKS ---
+  clearState();
+  if (test('respects ECC_DISABLED_HOOKS (skips when disabled)', () => {
+    const input = {
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/disabled.js', old_string: 'a', new_string: 'b' }
+    };
+    const result = runHook(input, {
+      ECC_DISABLED_HOOKS: 'pre:edit-write:gateguard-fact-force'
+    });
+
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce valid JSON output');
+    if (output.hookSpecificOutput) {
+      assert.notStrictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+        'should not deny when hook is disabled');
+    } else {
+      // When disabled, hook passes through raw input
+      assert.strictEqual(output.tool_name, 'Edit', 'pass-through should preserve input');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 10: MultiEdit gates first unchecked file ---
+  clearState();
+  if (test('denies first MultiEdit with unchecked file', () => {
+    const input = {
+      tool_name: 'MultiEdit',
+      tool_input: {
+        edits: [
+          { file_path: '/src/multi-a.js', old_string: 'a', new_string: 'b' },
+          { file_path: '/src/multi-b.js', old_string: 'c', new_string: 'd' }
+        ]
+      }
+    };
+    const result = runHook(input);
+    assert.strictEqual(result.code, 0, 'exit code should be 0');
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce JSON output');
+    assert.strictEqual(output.hookSpecificOutput.permissionDecision, 'deny');
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('Fact-Forcing Gate'));
+    assert.ok(output.hookSpecificOutput.permissionDecisionReason.includes('/src/multi-a.js'));
+  })) passed++; else failed++;
+
+  // --- Test 11: MultiEdit allows after all files gated ---
+  if (test('allows MultiEdit after all files gated', () => {
+    // multi-a.js was gated in test 10; gate multi-b.js
+    const input2 = {
+      tool_name: 'MultiEdit',
+      tool_input: { edits: [{ file_path: '/src/multi-b.js', old_string: 'c', new_string: 'd' }] }
+    };
+    runHook(input2); // gates multi-b.js
+
+    // Now both files are gated — retry should allow
+    const input3 = {
+      tool_name: 'MultiEdit',
+      tool_input: {
+        edits: [
+          { file_path: '/src/multi-a.js', old_string: 'a', new_string: 'b' },
+          { file_path: '/src/multi-b.js', old_string: 'c', new_string: 'd' }
+        ]
+      }
+    };
+    const result3 = runHook(input3);
+    const output3 = parseOutput(result3.stdout);
+    assert.ok(output3, 'should produce valid JSON');
+    if (output3.hookSpecificOutput) {
+      assert.notStrictEqual(output3.hookSpecificOutput.permissionDecision, 'deny',
+        'should allow MultiEdit after all files gated');
+    }
+  })) passed++; else failed++;
+
+  // --- Test 12: reads refresh active session state ---
+  clearState();
+  if (test('touches last_active on read so active sessions do not age out', () => {
+    const staleButActive = Date.now() - (29 * 60 * 1000);
+    writeState({
+      checked: ['/src/keep-alive.js'],
+      last_active: staleButActive
+    });
+
+    const before = JSON.parse(fs.readFileSync(stateFile, 'utf8'));
+    assert.strictEqual(before.last_active, staleButActive, 'seed state should use the expected timestamp');
+
+    const result = runHook({
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/keep-alive.js', old_string: 'a', new_string: 'b' }
+    });
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce valid JSON output');
+    if (output.hookSpecificOutput) {
+      assert.notStrictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+        'already-checked file should still be allowed');
+    }
+
+    const after = JSON.parse(fs.readFileSync(stateFile, 'utf8'));
+    assert.ok(after.last_active > staleButActive, 'successful reads should refresh last_active');
+  })) passed++; else failed++;
+
+  // --- Test 13: pruning preserves routine bash gate marker ---
+  clearState();
+  if (test('preserves __bash_session__ when pruning oversized state', () => {
+    const checked = ['__bash_session__'];
+    for (let i = 0; i < 80; i++) checked.push(`__destructive__${i}`);
+    for (let i = 0; i < 700; i++) checked.push(`/src/file-${i}.js`);
+    writeState({ checked, last_active: Date.now() });
+
+    runHook({
+      tool_name: 'Edit',
+      tool_input: { file_path: '/src/newly-gated.js', old_string: 'a', new_string: 'b' }
+    });
+
+    const result = runBashHook({
+      tool_name: 'Bash',
+      tool_input: { command: 'pwd' }
+    });
+    const output = parseOutput(result.stdout);
+    assert.ok(output, 'should produce valid JSON output');
+    if (output.hookSpecificOutput) {
+      assert.notStrictEqual(output.hookSpecificOutput.permissionDecision, 'deny',
+        'routine bash marker should survive pruning');
+    }
+
+    const persisted = JSON.parse(fs.readFileSync(stateFile, 'utf8'));
+    assert.ok(persisted.checked.includes('__bash_session__'), 'pruned state should retain __bash_session__');
+    assert.ok(persisted.checked.length <= 500, 'pruned state should still honor the checked-entry cap');
+  })) passed++; else failed++;
+
+  // Cleanup only the temp directory created by this test file.
+  if (!externalStateDir) {
+    try {
+      if (fs.existsSync(stateDir)) {
+        fs.rmSync(stateDir, { recursive: true, force: true });
+      }
+    } catch (err) {
+      console.error(`  [cleanup] failed to remove ${stateDir}: ${err.message}`);
+    }
+  }
+
+  console.log(`\n  ${passed} passed, ${failed} failed\n`);
+  process.exit(failed > 0 ? 1 : 0);
+}
+
+runTests();