diff --git a/sdks/go/cmd/elydora/plugins/hooktemplate.go b/sdks/go/cmd/elydora/plugins/hooktemplate.go
index d7bf2f3..2118efc 100644
--- a/sdks/go/cmd/elydora/plugins/hooktemplate.go
+++ b/sdks/go/cmd/elydora/plugins/hooktemplate.go
@@ -117,7 +117,7 @@ async function main() {
     if (age < CACHE_TTL_MS) {
       if (cache.status === 'frozen') {
         process.stderr.write('Agent "' + AGENT_NAME + '" is frozen by Elydora. Tool execution blocked.\n');
-        process.exitCode = 1;
+        process.exitCode = 2;
       }
       return; // Cache is fresh — use cached result
     }
@@ -161,7 +161,7 @@ async function main() {
 
       if (agentStatus === 'frozen') {
         process.stderr.write('Agent "' + AGENT_NAME + '" is frozen by Elydora. Tool execution blocked.\n');
-        process.exitCode = 1;
+        process.exitCode = 2;
       }
     }
   } catch {
diff --git a/sdks/go/cmd/elydora/plugins/hooktemplate_test.go b/sdks/go/cmd/elydora/plugins/hooktemplate_test.go
new file mode 100644
index 0000000..cb6bf94
--- /dev/null
+++ b/sdks/go/cmd/elydora/plugins/hooktemplate_test.go
@@ -0,0 +1,118 @@
+package plugins
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+const guardTestAgentID = "agent 1"
+
+func writeGuardFixture(t *testing.T, status string) (string, string, *httptest.Server) {
+	t.Helper()
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.EscapedPath() != "/v1/agents/agent%201" {
+			t.Errorf("request path = %q, want encoded agent path", r.URL.EscapedPath())
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(map[string]any{
+			"agent": map[string]string{"status": status},
+		})
+	}))
+	homeDir := t.TempDir()
+	agentDir := filepath.Join(homeDir, ".elydora", guardTestAgentID)
+	if err := os.MkdirAll(agentDir, 0755); err != nil {
+		t.Fatalf("create agent directory: %v", err)
+	}
+	config, err := json.Marshal(map[string]string{
+		"agent_id": guardTestAgentID,
+		"base_url": server.URL,
+	})
+	if err != nil {
+		t.Fatalf("marshal config: %v", err)
+	}
+	if err := os.WriteFile(filepath.Join(agentDir, "config.json"), config, 0600); err != nil {
+		t.Fatalf("write config: %v", err)
+	}
+	scriptPath := filepath.Join(homeDir, "guard.js")
+	if err := os.WriteFile(scriptPath, []byte(GenerateGuardScript("claudecode", guardTestAgentID)), 0755); err != nil {
+		t.Fatalf("write guard script: %v", err)
+	}
+	return scriptPath, homeDir, server
+}
+
+func runGuard(t *testing.T, scriptPath string, homeDir string) (int, string) {
+	t.Helper()
+	nodeBinary, err := exec.LookPath("node")
+	if err != nil {
+		t.Skip("Node.js is required to execute generated hook scripts")
+	}
+	cmd := exec.Command(nodeBinary, scriptPath)
+	cmd.Env = append(os.Environ(), "HOME="+homeDir, "USERPROFILE="+homeDir)
+	var stderr bytes.Buffer
+	cmd.Stderr = &stderr
+	err = cmd.Run()
+	if err == nil {
+		return 0, stderr.String()
+	}
+	exitError, ok := err.(*exec.ExitError)
+	if !ok {
+		t.Fatalf("run guard: %v", err)
+	}
+	return exitError.ExitCode(), stderr.String()
+}
+
+func TestGuardBlocksRemoteFrozenAgent(t *testing.T) {
+	scriptPath, homeDir, server := writeGuardFixture(t, "frozen")
+	defer server.Close()
+	exitCode, stderr := runGuard(t, scriptPath, homeDir)
+	if exitCode != 2 {
+		t.Fatalf("exit code = %d, want 2; stderr = %q", exitCode, stderr)
+	}
+	if !strings.Contains(stderr, "Tool execution blocked") {
+		t.Fatalf("stderr = %q, want blocking message", stderr)
+	}
+}
+
+func TestGuardAllowsActiveAgent(t *testing.T) {
+	scriptPath, homeDir, server := writeGuardFixture(t, "active")
+	defer server.Close()
+	exitCode, stderr := runGuard(t, scriptPath, homeDir)
+	if exitCode != 0 {
+		t.Fatalf("exit code = %d, want 0; stderr = %q", exitCode, stderr)
+	}
+	if stderr != "" {
+		t.Fatalf("stderr = %q, want empty output", stderr)
+	}
+}
+
+func TestGuardBlocksCachedFrozenAgent(t *testing.T) {
+	scriptPath, homeDir, server := writeGuardFixture(t, "active")
+	defer server.Close()
+	cache := map[string]any{
+		"status":    "frozen",
+		"cached_at": time.Now().Add(time.Minute).UnixMilli(),
+	}
+	cacheJSON, err := json.Marshal(cache)
+	if err != nil {
+		t.Fatalf("marshal cache: %v", err)
+	}
+	cachePath := filepath.Join(homeDir, ".elydora", guardTestAgentID, "status-cache.json")
+	if err := os.WriteFile(cachePath, cacheJSON, 0600); err != nil {
+		t.Fatalf("write cache: %v", err)
+	}
+	exitCode, stderr := runGuard(t, scriptPath, homeDir)
+	if exitCode != 2 {
+		t.Fatalf("exit code = %d, want 2; stderr = %q", exitCode, stderr)
+	}
+	if !strings.Contains(stderr, "Tool execution blocked") {
+		t.Fatalf("stderr = %q, want blocking message", stderr)
+	}
+}
diff --git a/sdks/node/package.json b/sdks/node/package.json
index 789a6e2..deb4070 100644
--- a/sdks/node/package.json
+++ b/sdks/node/package.json
@@ -13,6 +13,7 @@
   ],
   "scripts": {
     "build": "tsc && node scripts/postbuild.mjs",
+    "test": "npm run build && node --test",
     "prepublishOnly": "npm run build"
   },
   "engines": {
diff --git a/sdks/node/src/plugins/hook-template.ts b/sdks/node/src/plugins/hook-template.ts
index 3d1de7d..880d0ce 100644
--- a/sdks/node/src/plugins/hook-template.ts
+++ b/sdks/node/src/plugins/hook-template.ts
@@ -301,7 +301,7 @@ main();
  *
  * - Caches the agent status locally (60s TTL) to avoid hitting the API on every tool call
  * - Fails open: if the API is unreachable, tool execution is allowed
- * - If frozen: exits with code 1 to block the tool
+ * - If frozen: exits with code 2, the blocking code shared by supported hook CLIs
  */
 export function generateGuardScript(agentName: string, agentId: string): string {
   return `#!/usr/bin/env node
diff --git a/sdks/node/src/plugins/opencode.ts b/sdks/node/src/plugins/opencode.ts
index 59ba42a..906db75 100644
--- a/sdks/node/src/plugins/opencode.ts
+++ b/sdks/node/src/plugins/opencode.ts
@@ -25,21 +25,20 @@ export const ElydoraAuditPlugin = async (ctx) => {
   return {
     "tool.execute.before": async (input, output) => {
       // Guard — blocks tool if agent is frozen
+      let result;
       try {
-        const result = spawnSync('node', ['__ELYDORA_GUARD_SCRIPT_PATH__'], {
+        result = spawnSync('node', ['__ELYDORA_GUARD_SCRIPT_PATH__'], {
           timeout: 5000,
           stdio: ['pipe', 'ignore', 'pipe'],
         });
-        if (result.status === 2) {
-          const msg = result.stderr ? result.stderr.toString().trim() : 'Agent is frozen by Elydora.';
-          // Signal denial by setting a blocked flag
-          if (output && typeof output === 'object') {
-            output.blocked = true;
-            output.reason = msg;
-          }
-        }
       } catch {
         // Fail-open — allow if guard can't run
+        return;
+      }
+
+      if (result.status === 2) {
+        const msg = result.stderr ? result.stderr.toString().trim() : 'Agent is frozen by Elydora.';
+        throw new Error(msg);
       }
     },
 
diff --git a/sdks/node/test/guard-template.test.mjs b/sdks/node/test/guard-template.test.mjs
new file mode 100644
index 0000000..b112b69
--- /dev/null
+++ b/sdks/node/test/guard-template.test.mjs
@@ -0,0 +1,95 @@
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import { mkdtemp, mkdir, rm, writeFile } from 'node:fs/promises';
+import http from 'node:http';
+import os from 'node:os';
+import path from 'node:path';
+import test from 'node:test';
+
+import { generateGuardScript } from '../dist/plugins/hook-template.js';
+
+const AGENT_ID = 'agent-1';
+
+async function createFixture(status) {
+  const homeDir = await mkdtemp(path.join(os.tmpdir(), 'elydora-guard-'));
+  const agentDir = path.join(homeDir, '.elydora', AGENT_ID);
+  await mkdir(agentDir, { recursive: true });
+  const server = http.createServer((_request, response) => {
+    response.writeHead(200, { 'Content-Type': 'application/json' });
+    response.end(JSON.stringify({ agent: { status } }));
+  });
+  await new Promise((resolve) => server.listen(0, '127.0.0.1', resolve));
+  const address = server.address();
+  assert(address && typeof address === 'object');
+  await writeFile(
+    path.join(agentDir, 'config.json'),
+    JSON.stringify({ agent_id: AGENT_ID, base_url: `http://127.0.0.1:${address.port}` }),
+  );
+  const scriptPath = path.join(homeDir, 'guard.cjs');
+  await writeFile(scriptPath, generateGuardScript('claudecode', AGENT_ID));
+  return {
+    homeDir,
+    scriptPath,
+    async close() {
+      await new Promise((resolve, reject) => {
+        server.close((error) => (error ? reject(error) : resolve()));
+      });
+      await rm(homeDir, { recursive: true, force: true });
+    },
+  };
+}
+
+function runGuard(scriptPath, homeDir) {
+  return new Promise((resolve, reject) => {
+    const child = spawn(process.execPath, [scriptPath], {
+      env: { ...process.env, HOME: homeDir, USERPROFILE: homeDir },
+      stdio: ['ignore', 'pipe', 'pipe'],
+    });
+    let stdout = '';
+    let stderr = '';
+    child.stdout.on('data', (chunk) => { stdout += chunk; });
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('error', reject);
+    child.once('close', (code) => resolve({ code, stdout, stderr }));
+  });
+}
+
+test('frozen agents use the blocking exit code required by hook CLIs', async () => {
+  const fixture = await createFixture('frozen');
+  try {
+    const result = await runGuard(fixture.scriptPath, fixture.homeDir);
+    assert.equal(result.code, 2);
+    assert.match(result.stderr, /Tool execution blocked/);
+    assert.equal(result.stdout, '');
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('active agents allow tool execution', async () => {
+  const fixture = await createFixture('active');
+  try {
+    const result = await runGuard(fixture.scriptPath, fixture.homeDir);
+    assert.equal(result.code, 0);
+    assert.equal(result.stderr, '');
+    assert.equal(result.stdout, '');
+  } finally {
+    await fixture.close();
+  }
+});
+
+test('cached frozen status keeps the blocking exit code', async () => {
+  const fixture = await createFixture('active');
+  try {
+    await writeFile(
+      path.join(fixture.homeDir, '.elydora', AGENT_ID, 'status-cache.json'),
+      JSON.stringify({ status: 'frozen', cached_at: Date.now() }),
+    );
+    const result = await runGuard(fixture.scriptPath, fixture.homeDir);
+    assert.equal(result.code, 2);
+    assert.match(result.stderr, /Tool execution blocked/);
+    assert.equal(result.stdout, '');
+  } finally {
+    await fixture.close();
+  }
+});
diff --git a/sdks/node/test/opencode-plugin.test.mjs b/sdks/node/test/opencode-plugin.test.mjs
new file mode 100644
index 0000000..7dde4cb
--- /dev/null
+++ b/sdks/node/test/opencode-plugin.test.mjs
@@ -0,0 +1,66 @@
+import assert from 'node:assert/strict';
+import { spawn } from 'node:child_process';
+import { mkdtemp, mkdir, rm, writeFile } from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import { pathToFileURL } from 'node:url';
+import test from 'node:test';
+
+function runNode(args, env) {
+  return new Promise((resolve, reject) => {
+    const child = spawn(process.execPath, args, {
+      env: { ...process.env, ...env },
+      stdio: ['ignore', 'pipe', 'pipe'],
+    });
+    let stdout = '';
+    let stderr = '';
+    child.stdout.on('data', (chunk) => { stdout += chunk; });
+    child.stderr.on('data', (chunk) => { stderr += chunk; });
+    child.once('error', reject);
+    child.once('close', (code) => resolve({ code, stdout, stderr }));
+  });
+}
+
+test('OpenCode rejects tool execution when the Elydora guard blocks', async () => {
+  const homeDir = await mkdtemp(path.join(os.tmpdir(), 'elydora-opencode-'));
+  try {
+    const agentDir = path.join(homeDir, '.elydora', 'agent-1');
+    await mkdir(agentDir, { recursive: true });
+    const guardScriptPath = path.join(agentDir, 'guard.cjs');
+    const hookScriptPath = path.join(agentDir, 'hook.cjs');
+    await writeFile(
+      guardScriptPath,
+      "process.stderr.write('Agent is frozen by Elydora.'); process.exit(2);\n",
+    );
+    await writeFile(hookScriptPath, 'process.exit(0);\n');
+    const pluginModuleUrl = pathToFileURL(path.resolve('dist/plugins/opencode.js')).href;
+    const installScript = `
+      import { opencodePlugin } from ${JSON.stringify(pluginModuleUrl)};
+      await opencodePlugin.install(JSON.parse(process.env.ELYDORA_TEST_CONFIG));
+    `;
+    const installResult = await runNode(
+      ['--input-type=module', '--eval', installScript],
+      {
+        HOME: homeDir,
+        USERPROFILE: homeDir,
+        ELYDORA_TEST_CONFIG: JSON.stringify({ guardScriptPath, hookScriptPath }),
+      },
+    );
+    assert.equal(installResult.code, 0, installResult.stderr);
+    const generatedPath = path.join(
+      homeDir,
+      '.config',
+      'opencode',
+      'plugins',
+      'elydora-audit.mjs',
+    );
+    const generatedPlugin = await import(`${pathToFileURL(generatedPath).href}?test=${Date.now()}`);
+    const hooks = await generatedPlugin.ElydoraAuditPlugin({ project: { name: 'test' } });
+    await assert.rejects(
+      hooks['tool.execute.before']({ tool: 'bash' }, { args: { command: 'echo test' } }),
+      /Agent is frozen by Elydora/,
+    );
+  } finally {
+    await rm(homeDir, { recursive: true, force: true });
+  }
+});
diff --git a/sdks/python/elydora/plugins/hook_template.py b/sdks/python/elydora/plugins/hook_template.py
index 09cdd15..9e59879 100644
--- a/sdks/python/elydora/plugins/hook_template.py
+++ b/sdks/python/elydora/plugins/hook_template.py
@@ -297,7 +297,7 @@ def generate_guard_script(agent_name: str, agent_id: str) -> str:
       1. Reads agent config from ~/.elydora/{agent_id}/config.json
       2. Checks cached status from ~/.elydora/{agent_id}/status-cache.json (60s TTL)
       3. If cache is stale, fetches agent status from GET {base_url}/v1/agents/{agent_id}
-      4. If status is "frozen", writes error to stderr and exits with code 1 (blocks tool)
+      4. If status is "frozen", writes error to stderr and exits with blocking code 2
       5. Fail-open: if API unreachable or config missing, exits 0 (allow)
       6. Uses only stdlib — no external deps
     """
@@ -343,7 +343,7 @@ def main():
                 sys.stderr.write(
                     'Agent "' + AGENT_NAME + '" is frozen by Elydora. Tool execution blocked.\\n'
                 )
-                sys.exit(1)
+                sys.exit(2)
             return  # Cache is fresh — use cached result
     except Exception:
         pass  # No cache or invalid — need to check API
@@ -381,7 +381,7 @@ def main():
             sys.stderr.write(
                 'Agent "' + AGENT_NAME + '" is frozen by Elydora. Tool execution blocked.\\n'
             )
-            sys.exit(1)
+            sys.exit(2)
     except SystemExit:
         raise  # Re-raise sys.exit
     except Exception:
diff --git a/sdks/python/tests/test_guard_template.py b/sdks/python/tests/test_guard_template.py
new file mode 100644
index 0000000..a8383e4
--- /dev/null
+++ b/sdks/python/tests/test_guard_template.py
@@ -0,0 +1,106 @@
+from __future__ import annotations
+
+import json
+import os
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from pathlib import Path
+import subprocess
+import sys
+from threading import Thread
+
+from elydora.plugins.hook_template import generate_guard_script
+
+
+AGENT_ID = "agent 1"
+
+
+class StatusHandler(BaseHTTPRequestHandler):
+    status = "active"
+    request_path = ""
+
+    def do_GET(self) -> None:
+        type(self).request_path = self.path
+        body = json.dumps({"agent": {"status": type(self).status}}).encode()
+        self.send_response(200)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+    def log_message(self, _format: str, *_args: object) -> None:
+        return
+
+
+def create_guard(tmp_path: Path, status: str) -> tuple[Path, ThreadingHTTPServer]:
+    StatusHandler.status = status
+    StatusHandler.request_path = ""
+    server = ThreadingHTTPServer(("127.0.0.1", 0), StatusHandler)
+    Thread(target=server.serve_forever, daemon=True).start()
+    agent_dir = tmp_path / ".elydora" / AGENT_ID
+    agent_dir.mkdir(parents=True)
+    config = {
+        "agent_id": AGENT_ID,
+        "base_url": f"http://127.0.0.1:{server.server_port}",
+    }
+    (agent_dir / "config.json").write_text(json.dumps(config), encoding="utf-8")
+    script_path = tmp_path / "guard.py"
+    script_path.write_text(
+        generate_guard_script("claudecode", AGENT_ID),
+        encoding="utf-8",
+    )
+    return script_path, server
+
+
+def run_guard(script_path: Path, home_dir: Path) -> subprocess.CompletedProcess[str]:
+    env = {
+        **os.environ,
+        "HOME": str(home_dir),
+        "USERPROFILE": str(home_dir),
+    }
+    return subprocess.run(
+        [sys.executable, str(script_path)],
+        capture_output=True,
+        check=False,
+        env=env,
+        input="",
+        text=True,
+    )
+
+
+def test_remote_frozen_status_blocks_tool_execution(tmp_path: Path) -> None:
+    script_path, server = create_guard(tmp_path, "frozen")
+    try:
+        result = run_guard(script_path, tmp_path)
+    finally:
+        server.shutdown()
+        server.server_close()
+    assert result.returncode == 2
+    assert "Tool execution blocked" in result.stderr
+    assert StatusHandler.request_path == "/v1/agents/agent%201"
+
+
+def test_active_status_allows_tool_execution(tmp_path: Path) -> None:
+    script_path, server = create_guard(tmp_path, "active")
+    try:
+        result = run_guard(script_path, tmp_path)
+    finally:
+        server.shutdown()
+        server.server_close()
+    assert result.returncode == 0
+    assert result.stderr == ""
+
+
+def test_cached_frozen_status_uses_blocking_exit_code(tmp_path: Path) -> None:
+    script_path, server = create_guard(tmp_path, "active")
+    cache_path = tmp_path / ".elydora" / AGENT_ID / "status-cache.json"
+    cache_path.write_text(
+        json.dumps({"status": "frozen", "cached_at": 4_102_444_800}),
+        encoding="utf-8",
+    )
+    try:
+        result = run_guard(script_path, tmp_path)
+    finally:
+        server.shutdown()
+        server.server_close()
+    assert result.returncode == 2
+    assert "Tool execution blocked" in result.stderr