diff --git a/client/src/App.tsx b/client/src/App.tsx
index da9d2a0..7a5e208 100644
--- a/client/src/App.tsx
+++ b/client/src/App.tsx
@@ -1,6 +1,6 @@
 import { NavLink, Navigate, Route, Routes } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
-import { Globe, KeyRound, Monitor, ClipboardList, Activity } from 'lucide-react';
+import { Globe, KeyRound, Monitor, ClipboardList, Activity, KeySquare } from 'lucide-react';
 import type { LucideIcon } from 'lucide-react';
 import styles from './App.module.css';
 import { SidePanel, ThemeSwitcher } from './ui';
@@ -21,9 +21,14 @@ import { EditStepPage } from './pages/scenario/EditStepPage';
 import { RunsPage } from './pages/run/RunsPage';
 import { RunDetailPage } from './pages/run/RunDetailPage';
 import { AllRunsPage } from './pages/run/AllRunsPage';
+import { CredentialsPage } from './pages/credential/CredentialsPage';
+import { CreateCredentialPage } from './pages/credential/CreateCredentialPage';
+import { EditCredentialPage } from './pages/credential/EditCredentialPage';
+import { CredentialDetailPage } from './pages/credential/CredentialDetailPage';
 
 const NAV: { path: string; labelKey: string; Icon: LucideIcon }[] = [
   { path: '/environments', labelKey: 'nav.environments', Icon: Globe },
+  { path: '/credentials', labelKey: 'nav.credentials', Icon: KeySquare },
   { path: '/keys', labelKey: 'nav.keys', Icon: KeyRound },
   { path: '/sessions', labelKey: 'nav.sessions', Icon: Monitor },
   { path: '/scenarios', labelKey: 'nav.scenarios', Icon: ClipboardList },
@@ -78,6 +83,10 @@ export default function App() {
           <Route path="/scenarios/:id/runs" element={<RunsPage />} />
           <Route path="/scenarios/:id/runs/:runId" element={<RunDetailPage />} />
           <Route path="/scenarios/:id" element={<ScenarioDetailPage />} />
+          <Route path="/credentials" element={<CredentialsPage />} />
+          <Route path="/credentials/new" element={<CreateCredentialPage />} />
+          <Route path="/credentials/:id/edit" element={<EditCredentialPage />} />
+          <Route path="/credentials/:id" element={<CredentialDetailPage />} />
           <Route path="/runs" element={<AllRunsPage />} />
           <Route path="*" element={<Navigate to="/scenarios" replace />} />
         </Routes>
diff --git a/client/src/api/client.ts b/client/src/api/client.ts
index 4051308..ce08573 100644
--- a/client/src/api/client.ts
+++ b/client/src/api/client.ts
@@ -1,7 +1,9 @@
 import type {
   PaginatedResponse,
+  Credential,
   Environment,
   KeysResponse,
+  ScenarioCredential,
   Session,
   Scenario,
   ScenarioRun,
@@ -30,6 +32,32 @@ async function request<T>(path: string, init?: RequestInit): Promise<T> {
   return JSON.parse(text) as T;
 }
 
+// ── Credentials ───────────────────────────────────────────────────────────────
+
+export const credentials = {
+  list(page = 1, limit = 50): Promise<PaginatedResponse<Credential>> {
+    return request(`/credentials?page=${page}&limit=${limit}`);
+  },
+  get(id: number): Promise<Credential> {
+    return request(`/credentials/${id}`);
+  },
+  create(name: string, data?: string): Promise<Credential> {
+    return request('/credentials', {
+      method: 'POST',
+      body: JSON.stringify({ name, data }),
+    });
+  },
+  update(id: number, patch: Partial<Pick<Credential, 'name' | 'data'>>): Promise<Credential> {
+    return request(`/credentials/${id}`, {
+      method: 'PATCH',
+      body: JSON.stringify(patch),
+    });
+  },
+  remove(id: number): Promise<void> {
+    return request(`/credentials/${id}`, { method: 'DELETE' });
+  },
+};
+
 // ── Environments ──────────────────────────────────────────────────────────────
 
 export const environments = {
@@ -132,9 +160,28 @@ export const runs = {
   },
 };
 
-// ── Scenario Steps ────────────────────────────────────────────────────────────
+// ── Scenario Credentials ──────────────────────────────────────────────────────
 
+export const scenarioCredentials = {
+  list(scenarioId: number): Promise<ScenarioCredential[]> {
+    return request(`/scenarios/${scenarioId}/credentials`);
+  },
+  add(scenarioId: number, credentialId: number, alias: string): Promise<ScenarioCredential> {
+    return request(`/scenarios/${scenarioId}/credentials`, {
+      method: 'POST',
+      body: JSON.stringify({ credentialId, alias }),
+    });
+  },
+  remove(scenarioId: number, scCredId: number): Promise<void> {
+    return request(`/scenarios/${scenarioId}/credentials/${scCredId}`, {
+      method: 'DELETE',
+    });
+  },
+};
+
+// ── Scenario Steps ────────────────────────────────────────────────────────────
 export interface CreateStepPayload {
+  title?: string;
   order: number;
   type: 'login' | 'exec' | 'sign';
   sessionName: string;
@@ -143,6 +190,7 @@ export interface CreateStepPayload {
 }
 
 export interface UpdateStepPayload {
+  title?: string;
   order?: number;
   type?: 'login' | 'exec' | 'sign';
   sessionName?: string;
diff --git a/client/src/api/types.ts b/client/src/api/types.ts
index 565f833..c247e1d 100644
--- a/client/src/api/types.ts
+++ b/client/src/api/types.ts
@@ -24,6 +24,17 @@ export interface Environment {
   updatedAt: string;
 }
 
+// ── Credentials ───────────────────────────────────────────────────────────────
+
+export interface Credential {
+  id: number;
+  name: string;
+  data: string | null;
+  lastUsedAt: string | null;
+  createdAt: string;
+  updatedAt: string;
+}
+
 // ── Keys ──────────────────────────────────────────────────────────────────────
 
 export interface KeysResponse {
@@ -53,6 +64,7 @@ export interface ScenarioStep {
   scenarioId: number;
   order: number;
   type: StepType;
+  title: string | null;
   sessionName: string;
   execCode: string | null;
   validateCode: string | null;
@@ -60,10 +72,20 @@ export interface ScenarioStep {
   updatedAt: string;
 }
 
+export interface ScenarioCredential {
+  id: number;
+  scenarioId: number;
+  credentialId: number;
+  alias: string;
+  credential: Credential;
+  createdAt: string;
+}
+
 export interface Scenario {
   id: number;
   name: string;
   steps?: ScenarioStep[];
+  scenarioCredentials?: ScenarioCredential[];
   createdAt: string;
   updatedAt: string;
 }
diff --git a/client/src/i18n/locales/en.json b/client/src/i18n/locales/en.json
index 1532c02..39e03db 100644
--- a/client/src/i18n/locales/en.json
+++ b/client/src/i18n/locales/en.json
@@ -3,11 +3,13 @@
     "not_found": "Not found",
     "not_found_session": "Session {{id}} does not exist or has been deleted.",
     "not_found_environment": "Environment {{id}} does not exist or has been deleted.",
+    "not_found_credential": "Credential {{id}} does not exist or has been deleted.",
     "not_found_scenario": "Scenario {{id}} does not exist or has been deleted.",
     "generic": "Something went wrong. Please try again."
   },
   "nav": {
     "environments": "Environments",
+    "credentials": "Credentials",
     "keys": "Keys",
     "sessions": "Sessions",
     "scenarios": "Scenarios",
@@ -44,8 +46,32 @@
     "field_updated": "Updated",
     "section_urls": "URLs"
   },
+  "credentials": {
+    "title": "Credentials",
+    "empty": "No credentials yet.",
+    "loading": "Loading…",
+    "menu_label": "Credential options",
+    "action_edit": "Edit",
+    "action_delete": "Delete",
+    "action_add": "Add credential",
+    "action_save": "Create",
+    "action_update": "Save changes",
+    "action_cancel": "Cancel",
+    "create_title": "New Credential",
+    "edit_title": "Edit Credential",
+    "form_name": "Name",
+    "form_name_placeholder": "e.g. staging-api-key",
+    "form_name_required": "Name is required",
+    "form_data": "Data (JSON)",
+    "form_data_placeholder": "{\"token\": \"…\"}",
+    "form_data_invalid_json": "Must be valid JSON",
+    "field_id": "ID",
+    "field_last_used": "Last Used",
+    "field_created": "Created",
+    "field_updated": "Updated",
+    "section_data": "Data"
+  },
   "keys": {
-    "title": "Keys",
     "col_name": "Key name",
     "empty": "No key files found."
   },
@@ -81,6 +107,7 @@
     "field_updated": "Updated",
     "steps_heading": "Steps",
     "step_order": "#",
+    "step_title": "Title",
     "step_type": "Type",
     "step_session": "Session",
     "step_updated": "Updated",
@@ -94,7 +121,22 @@
     "edit_title": "Edit Scenario",
     "form_name": "Name",
     "form_name_placeholder": "e.g. Login flow",
-    "form_name_required": "Name is required"
+    "form_name_required": "Name is required",
+    "credentials_heading": "Credentials",
+    "cred_empty": "No credentials assigned.",
+    "cred_col_alias": "Alias",
+    "cred_col_name": "Credential",
+    "cred_col_added": "Added",
+    "cred_action_add": "Add credential",
+    "cred_action_remove": "Remove",
+    "cred_action_save": "Add",
+    "cred_action_cancel": "Cancel",
+    "cred_form_cred": "Credential",
+    "cred_form_cred_placeholder": "Select credential…",
+    "cred_form_cred_required": "Select a credential",
+    "cred_form_alias": "Alias",
+    "cred_form_alias_placeholder": "e.g. api_key",
+    "cred_form_alias_required": "Alias is required"
   },
   "theme": {
     "switch_to_light": "Switch to light theme",
@@ -121,6 +163,8 @@
     "action_cancel": "Cancel",
     "form_order": "Order",
     "form_order_invalid": "Order must be a non-negative integer",
+    "form_title": "Title",
+    "form_title_placeholder": "e.g. Check login page",
     "form_type": "Type",
     "form_session": "Session name",
     "form_session_placeholder": "e.g. my-session",
diff --git a/client/src/pages/Page.module.css b/client/src/pages/Page.module.css
index d0519a8..742003c 100644
--- a/client/src/pages/Page.module.css
+++ b/client/src/pages/Page.module.css
@@ -6,14 +6,15 @@
 }
 
 .sectionHeading {
-  margin: var(--space-6) 0 var(--space-3);
+  margin: 0;
+  line-height: 1;
   font-size: var(--font-size-md);
   font-weight: 600;
   color: var(--color-text);
 }
 
 .stepsSection {
-  margin-top: var(--space-2);
+  margin-top: var(--space-6);
 }
 
 .breadcrumbs {
@@ -311,3 +312,15 @@
 .envDetailUrlVal a:hover {
   text-decoration: underline;
 }
+
+/* ── Code block ────────────────────────────────────────────────────────── */
+
+.codeBlock {
+  margin: 0;
+  font-family: var(--font-mono, ui-monospace, monospace);
+  font-size: var(--font-size-sm);
+  color: var(--color-text);
+  white-space: pre-wrap;
+  word-break: break-all;
+  overflow-x: auto;
+}
diff --git a/client/src/pages/credential/CreateCredentialPage.tsx b/client/src/pages/credential/CreateCredentialPage.tsx
new file mode 100644
index 0000000..2e56606
--- /dev/null
+++ b/client/src/pages/credential/CreateCredentialPage.tsx
@@ -0,0 +1,100 @@
+import { useState } from 'react';
+import { useNavigate } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import { credentials } from '../../api';
+import { Breadcrumbs, Button, Card, Input, Textarea } from '../../ui';
+import styles from '../Page.module.css';
+
+export function CreateCredentialPage() {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+
+  const [name, setName] = useState('');
+  const [data, setData] = useState('');
+  const [nameError, setNameError] = useState('');
+  const [dataError, setDataError] = useState('');
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const handleSubmit = async (e: React.FormEvent) => {
+    e.preventDefault();
+    let valid = true;
+    if (!name.trim()) {
+      setNameError(t('credentials.form_name_required'));
+      valid = false;
+    }
+    if (data.trim()) {
+      try {
+        JSON.parse(data.trim());
+      } catch {
+        setDataError(t('credentials.form_data_invalid_json'));
+        valid = false;
+      }
+    }
+    if (!valid) return;
+    setSaving(true);
+    setError(null);
+    try {
+      const credential = await credentials.create(name.trim(), data.trim() || undefined);
+      navigate(`/credentials/${credential.id}`);
+    } catch (err) {
+      setError((err as Error).message);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  return (
+    <div>
+      <div className={styles.pageToolbar}>
+        <Breadcrumbs
+          items={[
+            { label: t('credentials.title'), onClick: () => navigate('/credentials') },
+            { label: t('credentials.create_title') },
+          ]}
+        />
+      </div>
+
+      {error && <p className={styles.error}>{error}</p>}
+
+      <form onSubmit={handleSubmit} noValidate>
+        <Card className={styles.formCard}>
+          <div className={styles.formFields}>
+            <Input
+              label={t('credentials.form_name')}
+              placeholder={t('credentials.form_name_placeholder')}
+              value={name}
+              onChange={(e) => {
+                setName(e.target.value);
+                setNameError('');
+              }}
+              error={nameError || undefined}
+              required
+              autoFocus
+            />
+            <Textarea
+              label={t('credentials.form_data')}
+              placeholder={t('credentials.form_data_placeholder')}
+              value={data}
+              onChange={(e) => {
+                setData(e.target.value);
+                setDataError('');
+              }}
+              error={dataError || undefined}
+              rows={6}
+            />
+          </div>
+
+          <div className={styles.formActions}>
+            <Button type="button" variant="secondary" onClick={() => navigate('/credentials')}>
+              {t('credentials.action_cancel')}
+            </Button>
+            <Button type="submit" loading={saving}>
+              {t('credentials.action_save')}
+            </Button>
+          </div>
+        </Card>
+      </form>
+    </div>
+  );
+}
diff --git a/client/src/pages/credential/CredentialDetailPage.tsx b/client/src/pages/credential/CredentialDetailPage.tsx
new file mode 100644
index 0000000..41fe258
--- /dev/null
+++ b/client/src/pages/credential/CredentialDetailPage.tsx
@@ -0,0 +1,118 @@
+import { useEffect, useState } from 'react';
+import { useNavigate, useParams } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import { Pencil, Trash2 } from 'lucide-react';
+import { credentials } from '../../api';
+import type { Credential } from '../../api';
+import { Breadcrumbs, Button, Card, DescriptionList, Notification, Timestamp } from '../../ui';
+import styles from '../Page.module.css';
+
+export function CredentialDetailPage() {
+  const { t } = useTranslation();
+  const { id } = useParams<{ id: string }>();
+  const navigate = useNavigate();
+  const [credential, setCredential] = useState<Credential | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    if (!id) return;
+    credentials
+      .get(Number(id))
+      .then(setCredential)
+      .catch((err: Error) => setError(err.message))
+      .finally(() => setLoading(false));
+  }, [id]);
+
+  const handleDelete = async () => {
+    if (!credential) return;
+    await credentials.remove(credential.id);
+    navigate('/credentials');
+  };
+
+  return (
+    <div>
+      <div className={styles.pageToolbar}>
+        <Breadcrumbs
+          items={[
+            { label: t('credentials.title'), onClick: () => navigate('/credentials') },
+            { label: credential?.name ?? `#${id}` },
+          ]}
+        />
+        {credential && (
+          <div className={styles.toolbarActions}>
+            <Button
+              variant="secondary"
+              size="sm"
+              onClick={() => navigate(`/credentials/${credential.id}/edit`)}
+            >
+              <Pencil size={14} />
+              {t('credentials.action_edit')}
+            </Button>
+            <Button variant="danger" size="sm" onClick={handleDelete}>
+              <Trash2 size={14} />
+              {t('credentials.action_delete')}
+            </Button>
+          </div>
+        )}
+      </div>
+
+      {error && (
+        <Notification
+          variant="error"
+          title={error.startsWith('404') ? t('errors.not_found') : undefined}
+        >
+          {error.startsWith('404') ? t('errors.not_found_credential', { id }) : error}
+        </Notification>
+      )}
+
+      {loading && <p className={styles.muted}>{t('credentials.loading')}</p>}
+
+      {credential && (
+        <>
+          <div className={styles.detailMeta}>
+            <DescriptionList
+              layout="comfortable"
+              items={[
+                { term: t('credentials.field_id'), detail: credential.id },
+                {
+                  term: t('credentials.field_last_used'),
+                  detail: credential.lastUsedAt ? (
+                    <Timestamp value={credential.lastUsedAt} />
+                  ) : (
+                    '—'
+                  ),
+                },
+                {
+                  term: t('credentials.field_created'),
+                  detail: <Timestamp value={credential.createdAt} />,
+                },
+                {
+                  term: t('credentials.field_updated'),
+                  detail: <Timestamp value={credential.updatedAt} />,
+                },
+              ]}
+            />
+          </div>
+
+          {credential.data && (
+            <>
+              <h2 className={styles.sectionHeading}>{t('credentials.section_data')}</h2>
+              <Card>
+                <pre className={styles.codeBlock}>
+                  {(() => {
+                    try {
+                      return JSON.stringify(JSON.parse(credential.data), null, 2);
+                    } catch {
+                      return credential.data;
+                    }
+                  })()}
+                </pre>
+              </Card>
+            </>
+          )}
+        </>
+      )}
+    </div>
+  );
+}
diff --git a/client/src/pages/credential/CredentialsPage.tsx b/client/src/pages/credential/CredentialsPage.tsx
new file mode 100644
index 0000000..2277012
--- /dev/null
+++ b/client/src/pages/credential/CredentialsPage.tsx
@@ -0,0 +1,130 @@
+import { useEffect, useState } from 'react';
+import { useNavigate } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import { Settings, Pencil, Trash2, Plus } from 'lucide-react';
+import { credentials } from '../../api';
+import type { Credential } from '../../api';
+import { Breadcrumbs, Button, Card, ContextMenu, DescriptionList, Timestamp } from '../../ui';
+import styles from '../Page.module.css';
+
+function CredentialCard({
+  credential,
+  onDelete,
+}: {
+  credential: Credential;
+  onDelete: (id: number) => void;
+}) {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+
+  const header = (
+    <div className={styles.envCardHeader}>
+      <span className={styles.envCardName}>{credential.name}</span>
+      <div onClick={(e) => e.stopPropagation()}>
+        <ContextMenu
+          align="right"
+          trigger={
+            <Button variant="ghost" size="sm" aria-label={t('credentials.menu_label')}>
+              <Settings size={14} />
+            </Button>
+          }
+          items={[
+            {
+              label: t('credentials.action_edit'),
+              icon: <Pencil size={14} />,
+              onClick: () => navigate(`/credentials/${credential.id}/edit`),
+            },
+            {
+              label: t('credentials.action_delete'),
+              icon: <Trash2 size={14} />,
+              variant: 'danger',
+              onClick: () => onDelete(credential.id),
+            },
+          ]}
+        />
+      </div>
+    </div>
+  );
+
+  const footer = (
+    <div className={styles.envCardFooter}>
+      <span className={styles.envCardId}>#{credential.id}</span>
+      <Timestamp value={credential.updatedAt} />
+    </div>
+  );
+
+  return (
+    <Card
+      className={styles.envCard}
+      header={header}
+      headerVariant="primary"
+      footer={footer}
+      onClick={() => navigate(`/credentials/${credential.id}`)}
+    >
+      <DescriptionList
+        layout="compact"
+        truncate
+        items={[
+          {
+            term: t('credentials.field_last_used'),
+            detail: credential.lastUsedAt ? <Timestamp value={credential.lastUsedAt} /> : '—',
+          },
+        ]}
+      />
+    </Card>
+  );
+}
+
+function AddCredentialCard() {
+  const { t } = useTranslation();
+  const navigate = useNavigate();
+  return (
+    <div className={styles.envCardAdd}>
+      <Button variant="ghost" onClick={() => navigate('/credentials/new')}>
+        <Plus size={16} />
+        {t('credentials.action_add')}
+      </Button>
+    </div>
+  );
+}
+
+export function CredentialsPage() {
+  const { t } = useTranslation();
+  const [items, setItems] = useState<Credential[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+
+  const load = () => {
+    credentials
+      .list()
+      .then((res) => setItems(res.data))
+      .catch((err: Error) => setError(err.message))
+      .finally(() => setLoading(false));
+  };
+
+  useEffect(() => {
+    load();
+  }, []);
+
+  const handleDelete = async (id: number) => {
+    await credentials.remove(id);
+    setItems((prev) => prev.filter((c) => c.id !== id));
+  };
+
+  return (
+    <div>
+      <Breadcrumbs items={[{ label: t('credentials.title') }]} className={styles.breadcrumbs} />
+      {error && <p className={styles.error}>{error}</p>}
+      {loading ? (
+        <p className={styles.muted}>{t('credentials.loading')}</p>
+      ) : (
+        <div className={styles.envGrid}>
+          {items.map((credential) => (
+            <CredentialCard key={credential.id} credential={credential} onDelete={handleDelete} />
+          ))}
+          <AddCredentialCard />
+        </div>
+      )}
+    </div>
+  );
+}
diff --git a/client/src/pages/credential/EditCredentialPage.tsx b/client/src/pages/credential/EditCredentialPage.tsx
new file mode 100644
index 0000000..0ccbffa
--- /dev/null
+++ b/client/src/pages/credential/EditCredentialPage.tsx
@@ -0,0 +1,131 @@
+import { useEffect, useState } from 'react';
+import { useNavigate, useParams } from 'react-router-dom';
+import { useTranslation } from 'react-i18next';
+import { credentials } from '../../api';
+import type { Credential } from '../../api';
+import { Breadcrumbs, Button, Card, Input, Textarea } from '../../ui';
+import styles from '../Page.module.css';
+
+export function EditCredentialPage() {
+  const { t } = useTranslation();
+  const { id } = useParams<{ id: string }>();
+  const navigate = useNavigate();
+
+  const [credential, setCredential] = useState<Credential | null>(null);
+  const [name, setName] = useState('');
+  const [data, setData] = useState('');
+  const [nameError, setNameError] = useState('');
+  const [dataError, setDataError] = useState('');
+  const [loading, setLoading] = useState(true);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    if (!id) return;
+    credentials
+      .get(Number(id))
+      .then((c) => {
+        setCredential(c);
+        setName(c.name);
+        setData(c.data ?? '');
+      })
+      .catch((err: Error) => setError(err.message))
+      .finally(() => setLoading(false));
+  }, [id]);
+
+  const handleSubmit = async (e: React.FormEvent) => {
+    e.preventDefault();
+    let valid = true;
+    if (!name.trim()) {
+      setNameError(t('credentials.form_name_required'));
+      valid = false;
+    }
+    if (data.trim()) {
+      try {
+        JSON.parse(data.trim());
+      } catch {
+        setDataError(t('credentials.form_data_invalid_json'));
+        valid = false;
+      }
+    }
+    if (!valid) return;
+    setSaving(true);
+    setError(null);
+    try {
+      await credentials.update(Number(id), {
+        name: name.trim(),
+        data: data.trim() || null,
+      });
+      navigate(`/credentials/${id}`);
+    } catch (err) {
+      setError((err as Error).message);
+    } finally {
+      setSaving(false);
+    }
+  };
+
+  return (
+    <div>
+      <div className={styles.pageToolbar}>
+        <Breadcrumbs
+          items={[
+            { label: t('credentials.title'), onClick: () => navigate('/credentials') },
+            {
+              label: credential?.name ?? `#${id}`,
+              onClick: () => navigate(`/credentials/${id}`),
+            },
+            { label: t('credentials.edit_title') },
+          ]}
+        />
+      </div>
+
+      {error && <p className={styles.error}>{error}</p>}
+      {loading && <p className={styles.muted}>{t('credentials.loading')}</p>}
+
+      {!loading && credential && (
+        <form onSubmit={handleSubmit} noValidate>
+          <Card className={styles.formCard}>
+            <div className={styles.formFields}>
+              <Input
+                label={t('credentials.form_name')}
+                placeholder={t('credentials.form_name_placeholder')}
+                value={name}
+                onChange={(e) => {
+                  setName(e.target.value);
+                  setNameError('');
+                }}
+                error={nameError || undefined}
+                required
+                autoFocus
+              />
+              <Textarea
+                label={t('credentials.form_data')}
+                placeholder={t('credentials.form_data_placeholder')}
+                value={data}
+                onChange={(e) => {
+                  setData(e.target.value);
+                  setDataError('');
+                }}
+                error={dataError || undefined}
+                rows={6}
+              />
+            </div>
+
+            <div className={styles.formActions}>
+              <Button
+                type="button"
+                variant="secondary"
+                onClick={() => navigate(`/credentials/${id}`)}
+              >
+                {t('credentials.action_cancel')}
+              </Button>
+              <Button type="submit" loading={saving}>
+                {t('credentials.action_update')}
+              </Button>
+            </div>
+          </Card>
+        </form>
+      )}
+    </div>
+  );
+}
diff --git a/client/src/pages/scenario/CreateStepPage.tsx b/client/src/pages/scenario/CreateStepPage.tsx
index 0272714..aebf8ce 100644
--- a/client/src/pages/scenario/CreateStepPage.tsx
+++ b/client/src/pages/scenario/CreateStepPage.tsx
@@ -16,6 +16,7 @@ export function CreateStepPage() {
 
   const [scenario, setScenario] = useState<Scenario | null>(null);
   const [order, setOrder] = useState('0');
+  const [title, setTitle] = useState('');
   const [type, setType] = useState<StepType>('exec');
   const [sessionName, setSessionName] = useState('');
   const [execCode, setExecCode] = useState('');
@@ -45,6 +46,7 @@ export function CreateStepPage() {
     try {
       await steps.create(Number(id), {
         order: Number(order),
+        title: title.trim() || undefined,
         type,
         sessionName: sessionName.trim(),
         execCode: execCode.trim() || undefined,
@@ -86,6 +88,12 @@ export function CreateStepPage() {
               onChange={(e) => setOrder(e.target.value)}
               error={errors.order}
             />
+            <Input
+              label={t('steps.form_title')}
+              placeholder={t('steps.form_title_placeholder')}
+              value={title}
+              onChange={(e) => setTitle(e.target.value)}
+            />
             <Select
               label={t('steps.form_type')}
               value={type}
diff --git a/client/src/pages/scenario/EditStepPage.tsx b/client/src/pages/scenario/EditStepPage.tsx
index c8cffd0..6013c4d 100644
--- a/client/src/pages/scenario/EditStepPage.tsx
+++ b/client/src/pages/scenario/EditStepPage.tsx
@@ -16,6 +16,7 @@ export function EditStepPage() {
   const [scenario, setScenario] = useState<Scenario | null>(null);
   const [step, setStep] = useState<ScenarioStep | null>(null);
   const [order, setOrder] = useState('');
+  const [title, setTitle] = useState('');
   const [type, setType] = useState<StepType>('exec');
   const [sessionName, setSessionName] = useState('');
   const [execCode, setExecCode] = useState('');
@@ -33,6 +34,7 @@ export function EditStepPage() {
         setScenario(sc);
         setStep(st);
         setOrder(String(st.order));
+        setTitle(st.title ?? '');
         setType(st.type);
         setSessionName(st.sessionName);
         setExecCode(st.execCode ?? '');
@@ -63,6 +65,7 @@ export function EditStepPage() {
     try {
       await steps.update(Number(id), Number(stepId), {
         order: Number(order),
+        title: title.trim() || undefined,
         type,
         sessionName: sessionName.trim(),
         execCode: execCode.trim() || undefined,
@@ -109,6 +112,12 @@ export function EditStepPage() {
                 }}
                 error={orderError || undefined}
               />
+              <Input
+                label={t('steps.form_title')}
+                placeholder={t('steps.form_title_placeholder')}
+                value={title}
+                onChange={(e) => setTitle(e.target.value)}
+              />
               <Select
                 label={t('steps.form_type')}
                 value={type}
diff --git a/client/src/pages/scenario/ScenarioDetailPage.tsx b/client/src/pages/scenario/ScenarioDetailPage.tsx
index 5941ad3..44dd277 100644
--- a/client/src/pages/scenario/ScenarioDetailPage.tsx
+++ b/client/src/pages/scenario/ScenarioDetailPage.tsx
@@ -2,15 +2,17 @@ import { useEffect, useState } from 'react';
 import { useNavigate, useParams } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
 import { Play, Pencil, Plus, History, Trash2 } from 'lucide-react';
-import { scenarios, steps } from '../../api';
-import type { Scenario, ScenarioStep } from '../../api';
+import { scenarios, steps, scenarioCredentials, credentials as credentialsApi } from '../../api';
+import type { Scenario, ScenarioStep, ScenarioCredential, Credential } from '../../api';
 import {
   Badge,
   Breadcrumbs,
   Button,
   Card,
   DescriptionList,
+  Input,
   Notification,
+  Select,
   Table,
   Timestamp,
   type TableColumn,
@@ -31,13 +33,30 @@ export function ScenarioDetailPage() {
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
 
+  // Credentials state
+  const [scenarioCreds, setScenarioCreds] = useState<ScenarioCredential[]>([]);
+  const [allCredentials, setAllCredentials] = useState<Credential[]>([]);
+  const [addCredOpen, setAddCredOpen] = useState(false);
+  const [addCredId, setAddCredId] = useState('');
+  const [addAlias, setAddAlias] = useState('');
+  const [addCredError, setAddCredError] = useState('');
+  const [addAliasError, setAddAliasError] = useState('');
+  const [addCredSaving, setAddCredSaving] = useState(false);
+
   useEffect(() => {
     if (!id) return;
     scenarios
       .get(Number(id))
-      .then(setScenario)
+      .then((s) => {
+        setScenario(s);
+        setScenarioCreds(s.scenarioCredentials ?? []);
+      })
       .catch((err: Error) => setError(err.message))
       .finally(() => setLoading(false));
+    credentialsApi
+      .list(1, 200)
+      .then((r) => setAllCredentials(r.data))
+      .catch(() => {});
   }, [id]);
 
   const handleRun = async () => {
@@ -59,6 +78,34 @@ export function ScenarioDetailPage() {
     );
   };
 
+  const handleAddCredential = async (e: React.FormEvent) => {
+    e.preventDefault();
+    let valid = true;
+    if (!addCredId) { setAddCredError(t('scenarios.cred_form_cred_required')); valid = false; }
+    if (!addAlias.trim()) { setAddAliasError(t('scenarios.cred_form_alias_required')); valid = false; }
+    if (!valid) return;
+    setAddCredSaving(true);
+    try {
+      const sc = await scenarioCredentials.add(Number(id), Number(addCredId), addAlias.trim());
+      // Re-fetch the credential object since the response may not include it
+      const full = await scenarioCredentials.list(Number(id));
+      setScenarioCreds(full);
+      void sc;
+      setAddCredOpen(false);
+      setAddCredId('');
+      setAddAlias('');
+    } catch (err) {
+      setAddCredError((err as Error).message);
+    } finally {
+      setAddCredSaving(false);
+    }
+  };
+
+  const handleRemoveCredential = async (scCredId: number) => {
+    await scenarioCredentials.remove(Number(id), scCredId);
+    setScenarioCreds((prev) => prev.filter((sc) => sc.id !== scCredId));
+  };
+
   const stepColumns: TableColumn<ScenarioStep>[] = [
     { key: 'order', header: t('scenarios.step_order'), render: (s) => s.order, width: 60 },
     {
@@ -67,7 +114,11 @@ export function ScenarioDetailPage() {
       width: 90,
       render: (s) => <Badge variant={STEP_TYPE_VARIANT[s.type] ?? 'neutral'}>{s.type}</Badge>,
     },
-    { key: 'session', header: t('scenarios.step_session'), render: (s) => s.sessionName },
+    {
+      key: 'title',
+      header: t('scenarios.step_title'),
+      render: (s) => s.title ?? <span style={{ color: 'var(--color-text-muted)', fontStyle: 'italic' }}>{s.sessionName}</span>,
+    },
     {
       key: 'updated',
       header: t('scenarios.step_updated'),
@@ -108,6 +159,40 @@ export function ScenarioDetailPage() {
     },
   ];
 
+  const credColumns: TableColumn<ScenarioCredential>[] = [
+    { key: 'alias', header: t('scenarios.cred_col_alias'), render: (sc) => sc.alias },
+    {
+      key: 'name',
+      header: t('scenarios.cred_col_name'),
+      render: (sc) => sc.credential?.name ?? `#${sc.credentialId}`,
+    },
+    {
+      key: 'added',
+      header: t('scenarios.cred_col_added'),
+      width: 140,
+      render: (sc) => <Timestamp value={sc.createdAt} />,
+    },
+    {
+      key: 'actions',
+      header: '',
+      width: 60,
+      align: 'right',
+      render: (sc) => (
+        <Button
+          size="sm"
+          variant="danger"
+          title={t('scenarios.cred_action_remove')}
+          onClick={(e) => {
+            e.stopPropagation();
+            handleRemoveCredential(sc.id);
+          }}
+        >
+          <Trash2 size={14} />
+        </Button>
+      ),
+    },
+  ];
+
   return (
     <div>
       <div className={styles.pageToolbar}>
@@ -199,6 +284,68 @@ export function ScenarioDetailPage() {
               </div>
             </div>
           )}
+
+          {/* ── Credentials section ──────────────────────────────────── */}
+          <div className={styles.stepsSection}>
+            <div className={styles.sectionToolbar}>
+              <h2 className={styles.sectionHeading}>{t('scenarios.credentials_heading')}</h2>
+              <Button size="sm" onClick={() => setAddCredOpen((v) => !v)}>
+                <Plus size={14} />
+                {t('scenarios.cred_action_add')}
+              </Button>
+            </div>
+
+            {addCredOpen && (
+              <Card className={styles.formCard} style={{ marginBottom: 'var(--space-4)' }}>
+                <form onSubmit={handleAddCredential} noValidate>
+                  <div className={styles.formFields}>
+                    <Select
+                      label={t('scenarios.cred_form_cred')}
+                      value={addCredId}
+                      onChange={(e) => { setAddCredId(e.target.value); setAddCredError(''); }}
+                      error={addCredError || undefined}
+                      options={[
+                        { value: '', label: t('scenarios.cred_form_cred_placeholder') },
+                        ...allCredentials.map((c) => ({ value: String(c.id), label: c.name })),
+                      ]}
+                    />
+                    <Input
+                      label={t('scenarios.cred_form_alias')}
+                      placeholder={t('scenarios.cred_form_alias_placeholder')}
+                      value={addAlias}
+                      onChange={(e) => { setAddAlias(e.target.value); setAddAliasError(''); }}
+                      error={addAliasError || undefined}
+                    />
+                  </div>
+                  <div className={styles.formActions}>
+                    <Button
+                      type="button"
+                      variant="secondary"
+                      size="sm"
+                      onClick={() => { setAddCredOpen(false); setAddCredId(''); setAddAlias(''); }}
+                    >
+                      {t('scenarios.cred_action_cancel')}
+                    </Button>
+                    <Button type="submit" size="sm" loading={addCredSaving}>
+                      {t('scenarios.cred_action_save')}
+                    </Button>
+                  </div>
+                </form>
+              </Card>
+            )}
+
+            {scenarioCreds.length > 0 ? (
+              <Table
+                columns={credColumns}
+                data={scenarioCreds}
+                rowKey={(sc) => sc.id}
+                loading={false}
+                emptyMessage=""
+              />
+            ) : (
+              <p className={styles.muted}>{t('scenarios.cred_empty')}</p>
+            )}
+          </div>
         </>
       )}
     </div>
diff --git a/client/src/ui/Textarea/Textarea.module.css b/client/src/ui/Textarea/Textarea.module.css
new file mode 100644
index 0000000..992926d
--- /dev/null
+++ b/client/src/ui/Textarea/Textarea.module.css
@@ -0,0 +1,60 @@
+.wrapper {
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-1);
+  font-family: var(--font-family);
+  width: 100%;
+}
+
+.label {
+  font-size: var(--font-size-sm);
+  font-weight: 500;
+  color: var(--color-text);
+}
+
+.textarea {
+  font-family: var(--font-family-mono, monospace);
+  font-size: var(--font-size-sm);
+  color: var(--color-text);
+  background: var(--color-bg);
+  border: var(--border-width) solid var(--color-border);
+  border-radius: var(--radius-md);
+  padding: var(--space-2) var(--space-3);
+  width: 100%;
+  outline: none;
+  resize: vertical;
+  transition: border-color var(--transition), box-shadow var(--transition);
+}
+
+.textarea::placeholder {
+  color: var(--color-text-muted);
+}
+
+.textarea:focus {
+  border-color: var(--color-primary);
+  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
+}
+
+.textarea:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+  background: var(--color-bg-subtle);
+}
+
+.hasError {
+  border-color: var(--color-error-fg);
+}
+.hasError:focus {
+  border-color: var(--color-error-fg);
+  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2);
+}
+
+.hint {
+  font-size: var(--font-size-xs);
+  color: var(--color-text-muted);
+}
+
+.error {
+  font-size: var(--font-size-xs);
+  color: var(--color-error-fg);
+}
diff --git a/client/src/ui/Textarea/Textarea.tsx b/client/src/ui/Textarea/Textarea.tsx
new file mode 100644
index 0000000..8f17343
--- /dev/null
+++ b/client/src/ui/Textarea/Textarea.tsx
@@ -0,0 +1,40 @@
+import React, { useId } from 'react';
+import styles from './Textarea.module.css';
+
+export interface TextareaProps
+  extends Omit<React.TextareaHTMLAttributes<HTMLTextAreaElement>, 'id'> {
+  label?: string;
+  hint?: string;
+  error?: string;
+}
+
+export function Textarea({ label, hint, error, className, ...props }: TextareaProps) {
+  const id = useId();
+  return (
+    <div className={styles.wrapper}>
+      {label && (
+        <label htmlFor={id} className={styles.label}>
+          {label}
+        </label>
+      )}
+      <textarea
+        id={id}
+        className={[styles.textarea, error ? styles.hasError : '', className]
+          .filter(Boolean)
+          .join(' ')}
+        aria-describedby={error ? `${id}-error` : hint ? `${id}-hint` : undefined}
+        aria-invalid={error ? true : undefined}
+        {...props}
+      />
+      {error ? (
+        <span id={`${id}-error`} className={styles.error} role="alert">
+          {error}
+        </span>
+      ) : hint ? (
+        <span id={`${id}-hint`} className={styles.hint}>
+          {hint}
+        </span>
+      ) : null}
+    </div>
+  );
+}
diff --git a/client/src/ui/index.ts b/client/src/ui/index.ts
index 7388532..4a4a33f 100644
--- a/client/src/ui/index.ts
+++ b/client/src/ui/index.ts
@@ -10,6 +10,9 @@ export type { BadgeProps, BadgeVariant } from './Badge/Badge';
 export { Input } from './Input/Input';
 export type { InputProps } from './Input/Input';
 
+export { Textarea } from './Textarea/Textarea';
+export type { TextareaProps } from './Textarea/Textarea';
+
 export { Select } from './Select/Select';
 export type { SelectProps, SelectOption } from './Select/Select';
 
diff --git a/client/vite.config.ts b/client/vite.config.ts
index 8c57bb9..5ab7eae 100644
--- a/client/vite.config.ts
+++ b/client/vite.config.ts
@@ -13,6 +13,7 @@ export default defineConfig({
   server: {
     proxy: {
       '/environments': 'http://localhost:13000',
+      '/credentials': 'http://localhost:13000',
       '/sessions': 'http://localhost:13000',
       '/scenarios': 'http://localhost:13000',
       '/keys': 'http://localhost:13000',
diff --git a/server/src/app.module.ts b/server/src/app.module.ts
index bcb5568..1caee78 100644
--- a/server/src/app.module.ts
+++ b/server/src/app.module.ts
@@ -9,12 +9,15 @@ import { BrowserModule } from "./browser/browser.module";
 import { SessionEntity } from "./session/session.entity";
 import { EnvironmentEntity } from "./environment/environment.entity";
 import { EnvironmentModule } from "./environment/environment.module";
+import { CredentialEntity } from "./credential/credential.entity";
+import { CredentialModule } from "./credential/credential.module";
 import { McpModule } from "./mcp/mcp.module";
 import { ScenarioEntity } from "./scenario/scenario.entity";
 import { ScenarioStepEntity } from "./scenario/scenario-step.entity";
 import { ScenarioRunEntity } from "./scenario/scenario-run.entity";
 import { ScenarioRunStepEntity } from "./scenario/scenario-run-step.entity";
 import { ScenarioRunLogEntity } from "./scenario/scenario-run-log.entity";
+import { ScenarioCredentialEntity } from "./scenario/scenario-credential.entity";
 import { ScenarioModule } from "./scenario/scenario.module";
 
 @Module({
@@ -33,11 +36,13 @@ import { ScenarioModule } from "./scenario/scenario.module";
         entities: [
           SessionEntity,
           EnvironmentEntity,
+          CredentialEntity,
           ScenarioEntity,
           ScenarioStepEntity,
           ScenarioRunEntity,
           ScenarioRunStepEntity,
           ScenarioRunLogEntity,
+          ScenarioCredentialEntity,
         ],
         synchronize: true,
       }),
@@ -45,6 +50,7 @@ import { ScenarioModule } from "./scenario/scenario.module";
     AuthModule,
     BrowserModule,
     EnvironmentModule,
+    CredentialModule,
     ScenarioModule,
     McpModule,
     HealthModule,
diff --git a/server/src/code-executor/code-executor.service.ts b/server/src/code-executor/code-executor.service.ts
index e35fe75..e6e8940 100644
--- a/server/src/code-executor/code-executor.service.ts
+++ b/server/src/code-executor/code-executor.service.ts
@@ -7,6 +7,7 @@ import { TraceLogger } from "../common/trace-logger";
 import { parse } from "acorn";
 import type { Page, BrowserContext } from "playwright";
 import { dumpDom } from "./dom-helpers";
+import type { EnvironmentUrls } from "../environment/environment.entity";
 
 export interface ExecResult {
   result: unknown;
@@ -47,6 +48,8 @@ export class CodeExecutorService {
     code: string,
     log?: ScriptLogger,
     getStepOutput?: (order: number) => Promise<unknown>,
+    credentials?: Record<string, unknown>,
+    environment?: EnvironmentUrls | null,
   ): Promise<ExecResult> {
     const scriptLog: ScriptLogger =
       log ?? ((level, msg) => this.logger[level](msg));
@@ -55,6 +58,9 @@ export class CodeExecutorService {
         .map((a) => (typeof a === "object" ? JSON.stringify(a) : String(a)))
         .join(" ");
 
+    const credMap: Record<string, unknown> = credentials ?? {};
+    const envUrls: EnvironmentUrls = environment ?? {};
+
     try {
       const pageHelpers = {
         dumpDom: (selector?: string) => dumpDom(page, selector),
@@ -62,6 +68,26 @@ export class CodeExecutorService {
         warn: (...args: unknown[]) => scriptLog("warn", toStr(args)),
         error: (...args: unknown[]) => scriptLog("error", toStr(args)),
         getStepOutput: getStepOutput ?? (() => Promise.resolve(null)),
+        getCredential: (alias: string): unknown => {
+          if (!(alias in credMap)) {
+            throw new Error(
+              `Credential alias "${alias}" not found in this scenario`,
+            );
+          }
+          return credMap[alias];
+        },
+        /** All URLs defined for the current environment (may be empty if no environment is set). */
+        env: { ...envUrls },
+        /** Returns the URL for the given key, or throws if it is not defined. */
+        getEnvUrl: (key: string): string => {
+          const value = envUrls[key];
+          if (value == null) {
+            throw new Error(
+              `Environment URL "${key}" is not defined for this environment`,
+            );
+          }
+          return value;
+        },
       };
 
       const fakeConsole = {
diff --git a/server/src/credential/credential.controller.ts b/server/src/credential/credential.controller.ts
new file mode 100644
index 0000000..ad54568
--- /dev/null
+++ b/server/src/credential/credential.controller.ts
@@ -0,0 +1,66 @@
+import {
+  Body,
+  Controller,
+  Delete,
+  Get,
+  HttpCode,
+  Param,
+  ParseIntPipe,
+  Patch,
+  Post,
+  Query,
+} from "@nestjs/common";
+import { ApiOperation, ApiResponse, ApiTags } from "@nestjs/swagger";
+import { CredentialService } from "./credential.service";
+import { CreateCredentialDto } from "./dto/create-credential.dto";
+import { UpdateCredentialDto } from "./dto/update-credential.dto";
+import { PaginationQueryDto } from "../common/dto/pagination.dto";
+import { CredentialOrderBy } from "./credential.service";
+
+@ApiTags("credentials")
+@Controller("credentials")
+export class CredentialController {
+  constructor(private readonly credentialService: CredentialService) {}
+
+  @Post()
+  @ApiOperation({ summary: "Create a new credential" })
+  @ApiResponse({ status: 201, description: "Credential created" })
+  create(@Body() dto: CreateCredentialDto) {
+    return this.credentialService.create(dto);
+  }
+
+  @Get()
+  @ApiOperation({ summary: "List all credentials (paginated)" })
+  @ApiResponse({ status: 200, description: "Paginated credentials" })
+  findAll(@Query() query: PaginationQueryDto<CredentialOrderBy>) {
+    return this.credentialService.findAll(query);
+  }
+
+  @Get(":id")
+  @ApiOperation({ summary: "Get credential by ID" })
+  @ApiResponse({ status: 200, description: "Credential record" })
+  @ApiResponse({ status: 404, description: "Credential not found" })
+  findOne(@Param("id", ParseIntPipe) id: number) {
+    return this.credentialService.findOne(id);
+  }
+
+  @Patch(":id")
+  @ApiOperation({ summary: "Update a credential" })
+  @ApiResponse({ status: 200, description: "Credential updated" })
+  @ApiResponse({ status: 404, description: "Credential not found" })
+  update(
+    @Param("id", ParseIntPipe) id: number,
+    @Body() dto: UpdateCredentialDto,
+  ) {
+    return this.credentialService.update(id, dto);
+  }
+
+  @Delete(":id")
+  @HttpCode(204)
+  @ApiOperation({ summary: "Delete a credential" })
+  @ApiResponse({ status: 204, description: "Credential deleted" })
+  @ApiResponse({ status: 404, description: "Credential not found" })
+  remove(@Param("id", ParseIntPipe) id: number) {
+    return this.credentialService.remove(id);
+  }
+}
diff --git a/server/src/credential/credential.entity.ts b/server/src/credential/credential.entity.ts
new file mode 100644
index 0000000..669200f
--- /dev/null
+++ b/server/src/credential/credential.entity.ts
@@ -0,0 +1,28 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+} from "typeorm";
+
+@Entity("credentials")
+export class CredentialEntity {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column()
+  name: string;
+
+  @Column("text", { nullable: true })
+  data: string | null;
+
+  @Column({ type: "datetime", nullable: true })
+  lastUsedAt: Date | null;
+
+  @CreateDateColumn()
+  createdAt: Date;
+
+  @UpdateDateColumn()
+  updatedAt: Date;
+}
diff --git a/server/src/credential/credential.module.ts b/server/src/credential/credential.module.ts
new file mode 100644
index 0000000..9c8f1cb
--- /dev/null
+++ b/server/src/credential/credential.module.ts
@@ -0,0 +1,13 @@
+import { Module } from "@nestjs/common";
+import { TypeOrmModule } from "@nestjs/typeorm";
+import { CredentialEntity } from "./credential.entity";
+import { CredentialService } from "./credential.service";
+import { CredentialController } from "./credential.controller";
+
+@Module({
+  imports: [TypeOrmModule.forFeature([CredentialEntity])],
+  controllers: [CredentialController],
+  providers: [CredentialService],
+  exports: [CredentialService],
+})
+export class CredentialModule {}
diff --git a/server/src/credential/credential.service.ts b/server/src/credential/credential.service.ts
new file mode 100644
index 0000000..7a6c31f
--- /dev/null
+++ b/server/src/credential/credential.service.ts
@@ -0,0 +1,56 @@
+import { Injectable, NotFoundException } from "@nestjs/common";
+import { InjectRepository } from "@nestjs/typeorm";
+import { Repository } from "typeorm";
+import { CredentialEntity } from "./credential.entity";
+import { CreateCredentialDto } from "./dto/create-credential.dto";
+import { UpdateCredentialDto } from "./dto/update-credential.dto";
+import {
+  PaginationQueryDto,
+  PaginatedResult,
+} from "../common/dto/pagination.dto";
+
+export type CredentialOrderBy = "id" | "name" | "lastUsedAt" | "createdAt" | "updatedAt";
+
+@Injectable()
+export class CredentialService {
+  constructor(
+    @InjectRepository(CredentialEntity)
+    private readonly repo: Repository<CredentialEntity>,
+  ) {}
+
+  async create(dto: CreateCredentialDto): Promise<CredentialEntity> {
+    return this.repo.save(this.repo.create({ ...dto, data: dto.data ?? null }));
+  }
+
+  async findAll(
+    query: PaginationQueryDto<CredentialOrderBy> = {},
+  ): Promise<PaginatedResult<CredentialEntity>> {
+    const page = query.page ?? 1;
+    const limit = query.limit ?? 20;
+    const orderBy = query.orderBy ?? "id";
+    const orderDir = query.orderDir ?? "ASC";
+    const [data, total] = await this.repo.findAndCount({
+      order: { [orderBy]: orderDir },
+      skip: (page - 1) * limit,
+      take: limit,
+    });
+    return { data, total, page, limit };
+  }
+
+  async findOne(id: number): Promise<CredentialEntity> {
+    const credential = await this.repo.findOneBy({ id });
+    if (!credential) throw new NotFoundException(`Credential ${id} not found`);
+    return credential;
+  }
+
+  async update(id: number, dto: UpdateCredentialDto): Promise<CredentialEntity> {
+    const credential = await this.findOne(id);
+    Object.assign(credential, dto);
+    return this.repo.save(credential);
+  }
+
+  async remove(id: number): Promise<void> {
+    await this.findOne(id);
+    await this.repo.delete(id);
+  }
+}
diff --git a/server/src/credential/dto/create-credential.dto.ts b/server/src/credential/dto/create-credential.dto.ts
new file mode 100644
index 0000000..908c64d
--- /dev/null
+++ b/server/src/credential/dto/create-credential.dto.ts
@@ -0,0 +1,17 @@
+import { ApiProperty, ApiPropertyOptional } from "@nestjs/swagger";
+import { IsNotEmpty, IsOptional, IsString } from "class-validator";
+
+export class CreateCredentialDto {
+  @ApiProperty({ example: "my-api-key" })
+  @IsString()
+  @IsNotEmpty()
+  name: string;
+
+  @ApiPropertyOptional({
+    description: "JSON-encoded credential payload",
+    example: '{"token":"abc123","secret":"xyz"}',
+  })
+  @IsOptional()
+  @IsString()
+  data?: string;
+}
diff --git a/server/src/credential/dto/update-credential.dto.ts b/server/src/credential/dto/update-credential.dto.ts
new file mode 100644
index 0000000..76e3f2b
--- /dev/null
+++ b/server/src/credential/dto/update-credential.dto.ts
@@ -0,0 +1,4 @@
+import { PartialType } from "@nestjs/swagger";
+import { CreateCredentialDto } from "./create-credential.dto";
+
+export class UpdateCredentialDto extends PartialType(CreateCredentialDto) {}
diff --git a/server/src/scenario/dto/add-scenario-credential.dto.ts b/server/src/scenario/dto/add-scenario-credential.dto.ts
new file mode 100644
index 0000000..0b42ffe
--- /dev/null
+++ b/server/src/scenario/dto/add-scenario-credential.dto.ts
@@ -0,0 +1,14 @@
+import { ApiProperty } from "@nestjs/swagger";
+import { IsInt, IsNotEmpty, IsPositive, IsString } from "class-validator";
+
+export class AddScenarioCredentialDto {
+  @ApiProperty({ example: 1 })
+  @IsInt()
+  @IsPositive()
+  credentialId: number;
+
+  @ApiProperty({ example: "api_key" })
+  @IsString()
+  @IsNotEmpty()
+  alias: string;
+}
diff --git a/server/src/scenario/dto/create-scenario-step.dto.ts b/server/src/scenario/dto/create-scenario-step.dto.ts
index b8afa1b..55d7489 100644
--- a/server/src/scenario/dto/create-scenario-step.dto.ts
+++ b/server/src/scenario/dto/create-scenario-step.dto.ts
@@ -10,6 +10,11 @@ import {
 import { StepType } from "../scenario-step.entity";
 
 export class CreateScenarioStepDto {
+  @ApiPropertyOptional({ example: "Check login page title" })
+  @IsOptional()
+  @IsString()
+  title?: string;
+
   @ApiProperty({ example: 0, description: "Execution order (ascending)" })
   @IsInt()
   @Min(0)
diff --git a/server/src/scenario/dto/update-scenario-step.dto.ts b/server/src/scenario/dto/update-scenario-step.dto.ts
index f9e81c5..a8ad1d4 100644
--- a/server/src/scenario/dto/update-scenario-step.dto.ts
+++ b/server/src/scenario/dto/update-scenario-step.dto.ts
@@ -10,6 +10,11 @@ import {
 import { StepType } from "../scenario-step.entity";
 
 export class UpdateScenarioStepDto {
+  @ApiPropertyOptional({ example: "Check login page title" })
+  @IsOptional()
+  @IsString()
+  title?: string;
+
   @ApiPropertyOptional({ example: 0 })
   @IsOptional()
   @IsInt()
diff --git a/server/src/scenario/scenario-credential.entity.ts b/server/src/scenario/scenario-credential.entity.ts
new file mode 100644
index 0000000..bc0464a
--- /dev/null
+++ b/server/src/scenario/scenario-credential.entity.ts
@@ -0,0 +1,38 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  ManyToOne,
+  JoinColumn,
+  CreateDateColumn,
+  Unique,
+} from "typeorm";
+import { ScenarioEntity } from "./scenario.entity";
+import { CredentialEntity } from "../credential/credential.entity";
+
+@Entity("scenario_credentials")
+@Unique(["scenarioId", "alias"])
+export class ScenarioCredentialEntity {
+  @PrimaryGeneratedColumn()
+  id: number;
+
+  @Column()
+  scenarioId: number;
+
+  @Column()
+  credentialId: number;
+
+  @Column()
+  alias: string;
+
+  @ManyToOne(() => ScenarioEntity, { onDelete: "CASCADE" })
+  @JoinColumn({ name: "scenarioId" })
+  scenario: ScenarioEntity;
+
+  @ManyToOne(() => CredentialEntity, { onDelete: "CASCADE", eager: true })
+  @JoinColumn({ name: "credentialId" })
+  credential: CredentialEntity;
+
+  @CreateDateColumn()
+  createdAt: Date;
+}
diff --git a/server/src/scenario/scenario-scheduler.service.ts b/server/src/scenario/scenario-scheduler.service.ts
index 64285af..5a3a19e 100644
--- a/server/src/scenario/scenario-scheduler.service.ts
+++ b/server/src/scenario/scenario-scheduler.service.ts
@@ -15,6 +15,9 @@ import type { ScriptLogger } from "../code-executor/code-executor.service";
 import { AuthService } from "../auth/auth.service";
 import { CodeExecutorService } from "../code-executor/code-executor.service";
 import { SessionService } from "../session/session.service";
+import { ScenarioService } from "./scenario.service";
+import { EnvironmentService } from "../environment/environment.service";
+import type { EnvironmentUrls } from "../environment/environment.entity";
 
 interface ValidateResult {
   success: boolean;
@@ -32,6 +35,10 @@ export class ScenarioSchedulerService {
   private readonly logger = new TraceLogger(ScenarioSchedulerService.name);
   private readonly activeRuns = new Set<number>();
   private readonly runBrowsers = new Map<number, BrowserHandle>();
+  // Cache credential maps per run (built once when a run starts)
+  private readonly runCredentials = new Map<number, Record<string, unknown>>();
+  // Cache environment URLs per run (resolved from the first login step)
+  private readonly runEnvironments = new Map<number, EnvironmentUrls>();
 
   constructor(
     @InjectRepository(ScenarioRunEntity)
@@ -43,6 +50,8 @@ export class ScenarioSchedulerService {
     private readonly authService: AuthService,
     private readonly codeExecutor: CodeExecutorService,
     private readonly sessionService: SessionService,
+    private readonly scenarioService: ScenarioService,
+    private readonly environmentService: EnvironmentService,
   ) {}
 
   private persistLog(
@@ -81,6 +90,30 @@ export class ScenarioSchedulerService {
     };
   }
 
+  /**
+   * Finds the first login step for a scenario and returns the environment URLs
+   * for the environment named in that step's execCode. Returns null if there is
+   * no login step or the environment cannot be found.
+   */
+  private async resolveRunEnvironment(
+    scenarioId: number,
+  ): Promise<EnvironmentUrls | null> {
+    try {
+      const scenario = await this.scenarioService.findOne(scenarioId);
+      const loginStep = scenario.steps.find((s) => s.type === "login");
+      if (!loginStep?.execCode) return null;
+      const params = JSON.parse(loginStep.execCode) as {
+        environmentName?: string;
+      };
+      if (!params.environmentName) return null;
+      const { data } = await this.environmentService.findAll({});
+      const env = data.find((e) => e.name === params.environmentName);
+      return env?.urls ?? null;
+    } catch {
+      return null;
+    }
+  }
+
   // ── Job: pick up pending runs and process each to completion ─────────────
 
   @Interval(1000)
@@ -92,6 +125,14 @@ export class ScenarioSchedulerService {
       run.status = "in_progress";
       await this.runRepo.save(run);
       this.logger.log(`Run #${run.id} → in_progress`);
+      // Pre-load credential map for the scenario
+      const credMap = await this.scenarioService
+        .buildCredentialMap(run.scenarioId)
+        .catch(() => ({} as Record<string, unknown>));
+      this.runCredentials.set(run.id, credMap);
+      // Resolve environment from the first login step (best-effort)
+      const envUrls = await this.resolveRunEnvironment(run.scenarioId);
+      if (envUrls) this.runEnvironments.set(run.id, envUrls);
       const traceId = crypto.randomUUID();
       void traceStorage.run({ traceId }, () =>
         this.processRunToCompletion(run.id),
@@ -114,8 +155,6 @@ export class ScenarioSchedulerService {
           order: { order: "ASC" },
         });
       }
-      // Guard: if there were no steps (or all steps already resolved via passStepRun),
-      // ensure the run is not left in in_progress.
       await this.runRepo
         .createQueryBuilder()
         .update()
@@ -129,6 +168,8 @@ export class ScenarioSchedulerService {
       await this.runRepo.update(runId, { status: "fail" });
     } finally {
       this.activeRuns.delete(runId);
+      this.runCredentials.delete(runId);
+      this.runEnvironments.delete(runId);
     }
   }
 
@@ -250,6 +291,8 @@ export class ScenarioSchedulerService {
         step.validateCode,
         this.stepLogger(stepRun.id, stepRun.runId),
         this.makeGetStepOutput(stepRun),
+        this.runCredentials.get(stepRun.runId),
+        this.runEnvironments.get(stepRun.runId),
       );
       const vr = this.parseValidateResult(result);
       if (!vr.success) throw new Error(vr.description ?? "Validation failed");
@@ -272,12 +315,16 @@ export class ScenarioSchedulerService {
       step.sessionName,
     );
     const getStepOutput = this.makeGetStepOutput(stepRun);
+    const creds = this.runCredentials.get(stepRun.runId);
+    const env = this.runEnvironments.get(stepRun.runId);
     const { result: execOutput } = await this.codeExecutor.execute(
       page,
       context,
       step.execCode,
       this.stepLogger(stepRun.id, stepRun.runId),
       getStepOutput,
+      creds,
+      env,
     );
     this.logger.log(`StepRun #${stepRun.id}: exec OK`);
 
@@ -289,6 +336,8 @@ export class ScenarioSchedulerService {
         step.validateCode,
         this.stepLogger(stepRun.id, stepRun.runId),
         getStepOutput,
+        creds,
+        env,
       );
       const vr = this.parseValidateResult(result);
       if (!vr.success) throw new Error(vr.description ?? "Validation failed");
@@ -327,6 +376,8 @@ export class ScenarioSchedulerService {
         step.validateCode,
         this.stepLogger(stepRun.id, stepRun.runId),
         this.makeGetStepOutput(stepRun),
+        this.runCredentials.get(stepRun.runId),
+        this.runEnvironments.get(stepRun.runId),
       );
       const vr = this.parseValidateResult(result);
       if (!vr.success) throw new Error(vr.description ?? "Validation failed");
diff --git a/server/src/scenario/scenario-step.entity.ts b/server/src/scenario/scenario-step.entity.ts
index 736369c..0f0344c 100644
--- a/server/src/scenario/scenario-step.entity.ts
+++ b/server/src/scenario/scenario-step.entity.ts
@@ -31,6 +31,9 @@ export class ScenarioStepEntity {
   @Column({ type: "text" })
   type: StepType;
 
+  @Column({ type: "text", nullable: true })
+  title: string | null;
+
   @Column({ type: "text" })
   sessionName: string;
 
diff --git a/server/src/scenario/scenario.controller.ts b/server/src/scenario/scenario.controller.ts
index cef3df2..e0715ed 100644
--- a/server/src/scenario/scenario.controller.ts
+++ b/server/src/scenario/scenario.controller.ts
@@ -16,6 +16,7 @@ import { CreateScenarioDto } from "./dto/create-scenario.dto";
 import { UpdateScenarioDto } from "./dto/update-scenario.dto";
 import { CreateScenarioStepDto } from "./dto/create-scenario-step.dto";
 import { UpdateScenarioStepDto } from "./dto/update-scenario-step.dto";
+import { AddScenarioCredentialDto } from "./dto/add-scenario-credential.dto";
 import { PaginationQueryDto } from "./dto/pagination-query.dto";
 import { ScenarioOrderBy } from "./scenario.service";
 import { RunsQueryDto } from "./dto/runs-query.dto";
@@ -140,6 +141,40 @@ export class ScenarioController {
     return this.scenarioService.removeStep(id, stepId);
   }
 
+  // ── Credentials ───────────────────────────────────────────────────────────
+
+  @Get(":id/credentials")
+  @ApiOperation({ summary: "List credentials assigned to a scenario" })
+  @ApiResponse({ status: 200 })
+  @ApiResponse({ status: 404, description: "Scenario not found" })
+  findScenarioCredentials(@Param("id", ParseIntPipe) id: number) {
+    return this.scenarioService.findScenarioCredentials(id);
+  }
+
+  @Post(":id/credentials")
+  @ApiOperation({ summary: "Add a credential to a scenario with an alias" })
+  @ApiResponse({ status: 201, description: "Credential added" })
+  @ApiResponse({ status: 404, description: "Scenario or credential not found" })
+  @ApiResponse({ status: 409, description: "Alias already used in this scenario" })
+  addScenarioCredential(
+    @Param("id", ParseIntPipe) id: number,
+    @Body() dto: AddScenarioCredentialDto,
+  ) {
+    return this.scenarioService.addScenarioCredential(id, dto);
+  }
+
+  @Delete(":id/credentials/:scCredId")
+  @HttpCode(204)
+  @ApiOperation({ summary: "Remove a credential from a scenario" })
+  @ApiResponse({ status: 204 })
+  @ApiResponse({ status: 404, description: "Scenario or credential assignment not found" })
+  removeScenarioCredential(
+    @Param("id", ParseIntPipe) id: number,
+    @Param("scCredId", ParseIntPipe) scCredId: number,
+  ) {
+    return this.scenarioService.removeScenarioCredential(id, scCredId);
+  }
+
   // ── Runs ──────────────────────────────────────────────────────────────────
 
   @Get(":id/runs")
diff --git a/server/src/scenario/scenario.entity.ts b/server/src/scenario/scenario.entity.ts
index deb9e90..e7c0ccb 100644
--- a/server/src/scenario/scenario.entity.ts
+++ b/server/src/scenario/scenario.entity.ts
@@ -7,6 +7,7 @@ import {
   OneToMany,
 } from "typeorm";
 import { ScenarioStepEntity } from "./scenario-step.entity";
+import { ScenarioCredentialEntity } from "./scenario-credential.entity";
 
 @Entity("scenarios")
 export class ScenarioEntity {
@@ -22,6 +23,12 @@ export class ScenarioEntity {
   })
   steps: ScenarioStepEntity[];
 
+  @OneToMany(() => ScenarioCredentialEntity, (sc) => sc.scenario, {
+    cascade: true,
+    eager: false,
+  })
+  scenarioCredentials: ScenarioCredentialEntity[];
+
   @CreateDateColumn()
   createdAt: Date;
 
diff --git a/server/src/scenario/scenario.module.ts b/server/src/scenario/scenario.module.ts
index 353f56d..9397d60 100644
--- a/server/src/scenario/scenario.module.ts
+++ b/server/src/scenario/scenario.module.ts
@@ -5,12 +5,15 @@ import { ScenarioStepEntity } from "./scenario-step.entity";
 import { ScenarioRunEntity } from "./scenario-run.entity";
 import { ScenarioRunStepEntity } from "./scenario-run-step.entity";
 import { ScenarioRunLogEntity } from "./scenario-run-log.entity";
+import { ScenarioCredentialEntity } from "./scenario-credential.entity";
+import { CredentialEntity } from "../credential/credential.entity";
 import { ScenarioService } from "./scenario.service";
 import { ScenarioController } from "./scenario.controller";
 import { ScenarioSchedulerService } from "./scenario-scheduler.service";
 import { AuthModule } from "../auth/auth.module";
 import { CodeExecutorModule } from "../code-executor/code-executor.module";
 import { SessionModule } from "../session/session.module";
+import { EnvironmentModule } from "../environment/environment.module";
 
 @Module({
   imports: [
@@ -20,10 +23,13 @@ import { SessionModule } from "../session/session.module";
       ScenarioRunEntity,
       ScenarioRunStepEntity,
       ScenarioRunLogEntity,
+      ScenarioCredentialEntity,
+      CredentialEntity,
     ]),
     AuthModule,
     CodeExecutorModule,
     SessionModule,
+    EnvironmentModule,
   ],
   controllers: [ScenarioController],
   providers: [ScenarioService, ScenarioSchedulerService],
diff --git a/server/src/scenario/scenario.service.ts b/server/src/scenario/scenario.service.ts
index 08aeb84..5cc94a7 100644
--- a/server/src/scenario/scenario.service.ts
+++ b/server/src/scenario/scenario.service.ts
@@ -1,4 +1,4 @@
-import { Injectable, NotFoundException } from "@nestjs/common";
+import { ConflictException, Injectable, NotFoundException } from "@nestjs/common";
 import { InjectRepository } from "@nestjs/typeorm";
 import { Repository } from "typeorm";
 import { ScenarioEntity } from "./scenario.entity";
@@ -6,10 +6,13 @@ import { ScenarioStepEntity } from "./scenario-step.entity";
 import { ScenarioRunEntity } from "./scenario-run.entity";
 import { ScenarioRunStepEntity } from "./scenario-run-step.entity";
 import { ScenarioRunLogEntity } from "./scenario-run-log.entity";
+import { ScenarioCredentialEntity } from "./scenario-credential.entity";
+import { CredentialEntity } from "../credential/credential.entity";
 import { CreateScenarioDto } from "./dto/create-scenario.dto";
 import { UpdateScenarioDto } from "./dto/update-scenario.dto";
 import { CreateScenarioStepDto } from "./dto/create-scenario-step.dto";
 import { UpdateScenarioStepDto } from "./dto/update-scenario-step.dto";
+import { AddScenarioCredentialDto } from "./dto/add-scenario-credential.dto";
 import {
   PaginationQueryDto,
   PaginatedResult,
@@ -33,6 +36,10 @@ export class ScenarioService {
     private readonly runStepRepo: Repository<ScenarioRunStepEntity>,
     @InjectRepository(ScenarioRunLogEntity)
     private readonly runLogRepo: Repository<ScenarioRunLogEntity>,
+    @InjectRepository(ScenarioCredentialEntity)
+    private readonly scenarioCredRepo: Repository<ScenarioCredentialEntity>,
+    @InjectRepository(CredentialEntity)
+    private readonly credentialRepo: Repository<CredentialEntity>,
   ) {}
 
   // ── Scenarios ─────────────────────────────────────────────────────────────
@@ -59,7 +66,7 @@ export class ScenarioService {
   async findOne(id: number): Promise<ScenarioEntity> {
     const scenario = await this.scenarioRepo.findOne({
       where: { id },
-      relations: ["steps"],
+      relations: ["steps", "scenarioCredentials", "scenarioCredentials.credential"],
       order: { steps: { order: "ASC" } },
     });
     if (!scenario) throw new NotFoundException(`Scenario ${id} not found`);
@@ -121,6 +128,84 @@ export class ScenarioService {
     await this.stepRepo.delete(stepId);
   }
 
+  // ── Scenario Credentials ──────────────────────────────────────────────────
+
+  async findScenarioCredentials(
+    scenarioId: number,
+  ): Promise<ScenarioCredentialEntity[]> {
+    await this.findOne(scenarioId); // 404 guard
+    return this.scenarioCredRepo.find({
+      where: { scenarioId },
+      relations: ["credential"],
+      order: { alias: "ASC" },
+    });
+  }
+
+  async addScenarioCredential(
+    scenarioId: number,
+    dto: AddScenarioCredentialDto,
+  ): Promise<ScenarioCredentialEntity> {
+    await this.findOne(scenarioId); // 404 guard
+    const credential = await this.credentialRepo.findOneBy({
+      id: dto.credentialId,
+    });
+    if (!credential)
+      throw new NotFoundException(`Credential ${dto.credentialId} not found`);
+    const existing = await this.scenarioCredRepo.findOneBy({
+      scenarioId,
+      alias: dto.alias,
+    });
+    if (existing)
+      throw new ConflictException(
+        `Alias "${dto.alias}" already used in this scenario`,
+      );
+    const sc = this.scenarioCredRepo.create({
+      scenarioId,
+      credentialId: dto.credentialId,
+      alias: dto.alias,
+    });
+    return this.scenarioCredRepo.save(sc);
+  }
+
+  async removeScenarioCredential(
+    scenarioId: number,
+    scCredId: number,
+  ): Promise<void> {
+    await this.findOne(scenarioId); // 404 guard
+    const sc = await this.scenarioCredRepo.findOneBy({
+      id: scCredId,
+      scenarioId,
+    });
+    if (!sc)
+      throw new NotFoundException(
+        `Scenario credential ${scCredId} not found in scenario ${scenarioId}`,
+      );
+    await this.scenarioCredRepo.delete(scCredId);
+  }
+
+  /**
+   * Builds a map of alias → parsed credential data for use in code execution.
+   * Returns null values for credentials with no data.
+   */
+  async buildCredentialMap(scenarioId: number): Promise<Record<string, unknown>> {
+    const scs = await this.findScenarioCredentials(scenarioId);
+    const map: Record<string, unknown> = {};
+    for (const sc of scs) {
+      let parsed: unknown = null;
+      if (sc.credential.data) {
+        try {
+          parsed = JSON.parse(sc.credential.data);
+        } catch {
+          parsed = sc.credential.data;
+        }
+      }
+      map[sc.alias] = parsed;
+    }
+    return map;
+  }
+
+  // ── Runs ──────────────────────────────────────────────────────────────────
+
   async findRuns(
     scenarioId: number,
     query: RunsQueryDto,