diff --git a/src/app/models/assistant.ts b/src/app/models/assistant.ts
index 1622875..234d024 100644
--- a/src/app/models/assistant.ts
+++ b/src/app/models/assistant.ts
@@ -57,9 +57,34 @@ export type AssistantPhaseModels = {
 export type AssistantLlmSelection = {
   provider: string;
   model: string;
+  credentialId?: string;
   phaseModels?: AssistantPhaseModels;
 };
 
+export type VaultSecret = {
+  id: string;
+  label: string;
+  provider: string;
+  description?: string;
+  active: boolean;
+  lastUsedAt?: string;
+  maskedPreview?: string;
+};
+
+export type VaultSecretCreateRequest = {
+  label: string;
+  provider: string;
+  description?: string;
+  value: string;
+};
+
+export type VaultSecretUpdateRequest = {
+  label?: string;
+  description?: string;
+  active?: boolean;
+  value?: string;
+};
+
 export type AssistantSessionRequest = {
   llmSelection?: AssistantLlmSelection;
 };
diff --git a/src/app/models/llm-provider.ts b/src/app/models/llm-provider.ts
new file mode 100644
index 0000000..67eeebf
--- /dev/null
+++ b/src/app/models/llm-provider.ts
@@ -0,0 +1,11 @@
+export type LlmProviderCapability = {
+  name: string;
+  requiresCredential: boolean;
+};
+
+export type ExecutionVaultCredential = {
+  id: string;
+  label: string;
+  description?: string;
+  provider: string;
+};
diff --git a/src/app/services/llm-provider/execution-vault-credentials-call.base.ts b/src/app/services/llm-provider/execution-vault-credentials-call.base.ts
new file mode 100644
index 0000000..f93f106
--- /dev/null
+++ b/src/app/services/llm-provider/execution-vault-credentials-call.base.ts
@@ -0,0 +1,6 @@
+import { ExecutionVaultCredential } from '@models/llm-provider';
+import { Observable } from 'rxjs';
+
+export abstract class ExecutionVaultCredentialsCallServiceBase {
+  abstract listForProvider(provider: string): Observable<ExecutionVaultCredential[]>;
+}
diff --git a/src/app/services/llm-provider/execution-vault-credentials-call.fake.ts b/src/app/services/llm-provider/execution-vault-credentials-call.fake.ts
new file mode 100644
index 0000000..7f7717f
--- /dev/null
+++ b/src/app/services/llm-provider/execution-vault-credentials-call.fake.ts
@@ -0,0 +1,15 @@
+import { ExecutionVaultCredential } from '@models/llm-provider';
+import { Observable, of } from 'rxjs';
+import { vaultFakeStore } from '@services/vault/vault-fake-store';
+import { ExecutionVaultCredentialsCallServiceBase } from './execution-vault-credentials-call.base';
+
+export class ExecutionVaultCredentialsCallServiceFake extends ExecutionVaultCredentialsCallServiceBase {
+  override listForProvider(provider: string): Observable<ExecutionVaultCredential[]> {
+    return of(vaultFakeStore.listActiveByProvider(provider).map((secret) => ({
+      id: secret.id,
+      label: secret.label,
+      description: secret.description,
+      provider: secret.provider
+    })));
+  }
+}
diff --git a/src/app/services/llm-provider/execution-vault-credentials-call.spec.ts b/src/app/services/llm-provider/execution-vault-credentials-call.spec.ts
new file mode 100644
index 0000000..5b2c04d
--- /dev/null
+++ b/src/app/services/llm-provider/execution-vault-credentials-call.spec.ts
@@ -0,0 +1,49 @@
+import { provideHttpClient } from '@angular/common/http';
+import { HttpTestingController, provideHttpClientTesting } from '@angular/common/http/testing';
+import { TestBed } from '@angular/core/testing';
+import { environment } from '@environment';
+import { firstValueFrom } from 'rxjs';
+import { ExecutionVaultCredentialsCallService } from './execution-vault-credentials-call';
+
+describe('ExecutionVaultCredentialsCallService', () => {
+  let service: ExecutionVaultCredentialsCallService;
+  let httpMock: HttpTestingController;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [ExecutionVaultCredentialsCallService, provideHttpClient(), provideHttpClientTesting()]
+    });
+    service = TestBed.inject(ExecutionVaultCredentialsCallService);
+    httpMock = TestBed.inject(HttpTestingController);
+  });
+
+  afterEach(() => httpMock.verify());
+
+  it('requests the credentials of a single provider and maps the vault secret id', async () => {
+    const result = firstValueFrom(service.listForProvider('OpenAI'));
+    const request = httpMock.expectOne(
+      (candidate) => candidate.url === `${environment.apiUrl}/secure-retriever/UserSecrets/forProvider/items`
+    );
+
+    expect(request.request.params.get('provider')).toBe('OpenAI');
+    request.flush({
+      items: [
+        {
+          data: 'vault-secret-1',
+          descriptor: { label: 'OpenAI key', description: 'shared', meta: { provider: 'OpenAI' } }
+        },
+        {
+          data: '',
+          descriptor: { label: 'Broken entry', meta: { provider: 'OpenAI' } }
+        }
+      ]
+    });
+
+    await expect(result).resolves.toEqual([{
+      id: 'vault-secret-1',
+      label: 'OpenAI key',
+      description: 'shared',
+      provider: 'OpenAI'
+    }]);
+  });
+});
diff --git a/src/app/services/llm-provider/execution-vault-credentials-call.ts b/src/app/services/llm-provider/execution-vault-credentials-call.ts
new file mode 100644
index 0000000..ea60b78
--- /dev/null
+++ b/src/app/services/llm-provider/execution-vault-credentials-call.ts
@@ -0,0 +1,43 @@
+import { HttpClient, HttpParams } from '@angular/common/http';
+import { inject } from '@angular/core';
+import { environment } from '@environment';
+import { ExecutionVaultCredential } from '@models/llm-provider';
+import { map, Observable } from 'rxjs';
+import { ExecutionVaultCredentialsCallServiceBase } from './execution-vault-credentials-call.base';
+
+export class ExecutionVaultCredentialsCallService extends ExecutionVaultCredentialsCallServiceBase {
+  private readonly http = inject(HttpClient);
+
+  override listForProvider(provider: string): Observable<ExecutionVaultCredential[]> {
+    const params = new HttpParams().set('provider', provider);
+    return this.http.get<unknown>(
+      `${environment.apiUrl}/secure-retriever/UserSecrets/forProvider/items`,
+      { params }
+    ).pipe(map((raw) => normalizeCredentials(raw)));
+  }
+}
+
+function normalizeCredentials(raw: unknown): ExecutionVaultCredential[] {
+  const items = Array.isArray(raw)
+    ? raw
+    : raw && typeof raw === 'object'
+      ? ((raw as Record<string, unknown>)['items'] ?? (raw as Record<string, unknown>)['values'] ?? [])
+      : [];
+  if (!Array.isArray(items)) return [];
+
+  return items.map((item) => {
+    const value = item && typeof item === 'object' ? item as Record<string, unknown> : {};
+    const descriptor = value['descriptor'] && typeof value['descriptor'] === 'object'
+      ? value['descriptor'] as Record<string, unknown>
+      : {};
+    const meta = descriptor['meta'] && typeof descriptor['meta'] === 'object'
+      ? descriptor['meta'] as Record<string, unknown>
+      : {};
+    return {
+      id: String(value['data'] ?? ''),
+      label: String(descriptor['label'] ?? 'Credential'),
+      description: typeof descriptor['description'] === 'string' ? descriptor['description'] : undefined,
+      provider: String(meta['provider'] ?? '')
+    };
+  }).filter((item) => item.id.length > 0);
+}
diff --git a/src/app/services/llm-provider/execution-vault-credentials.ts b/src/app/services/llm-provider/execution-vault-credentials.ts
new file mode 100644
index 0000000..8ced4a1
--- /dev/null
+++ b/src/app/services/llm-provider/execution-vault-credentials.ts
@@ -0,0 +1,15 @@
+import { Injectable } from '@angular/core';
+import { environment } from '@environment';
+import { ExecutionVaultCredential } from '@models/llm-provider';
+import { Observable } from 'rxjs';
+import { ExecutionVaultCredentialsCallServiceBase } from './execution-vault-credentials-call.base';
+
+@Injectable({ providedIn: 'root' })
+export class ExecutionVaultCredentialsService {
+  executionVaultCredentialsCallService: ExecutionVaultCredentialsCallServiceBase =
+    new environment.executionVaultCredentialsCallService();
+
+  listForProvider(provider: string): Observable<ExecutionVaultCredential[]> {
+    return this.executionVaultCredentialsCallService.listForProvider(provider);
+  }
+}
diff --git a/src/app/services/llm-provider/llm-provider-call.base.ts b/src/app/services/llm-provider/llm-provider-call.base.ts
new file mode 100644
index 0000000..3142acc
--- /dev/null
+++ b/src/app/services/llm-provider/llm-provider-call.base.ts
@@ -0,0 +1,6 @@
+import { LlmProviderCapability } from '@models/llm-provider';
+import { Observable } from 'rxjs';
+
+export abstract class LlmProviderCallServiceBase {
+  abstract listCapabilities(): Observable<LlmProviderCapability[]>;
+}
diff --git a/src/app/services/llm-provider/llm-provider-call.fake.ts b/src/app/services/llm-provider/llm-provider-call.fake.ts
new file mode 100644
index 0000000..3e3fff0
--- /dev/null
+++ b/src/app/services/llm-provider/llm-provider-call.fake.ts
@@ -0,0 +1,13 @@
+import { LlmProviderCapability } from '@models/llm-provider';
+import { Observable, of } from 'rxjs';
+import { LlmProviderCallServiceBase } from './llm-provider-call.base';
+
+export class LlmProviderCallServiceFake extends LlmProviderCallServiceBase {
+  override listCapabilities(): Observable<LlmProviderCapability[]> {
+    return of([
+      { name: 'InternalOllama', requiresCredential: false },
+      { name: 'testProvider', requiresCredential: true },
+      { name: 'Gemini', requiresCredential: true }
+    ]);
+  }
+}
diff --git a/src/app/services/llm-provider/llm-provider-call.spec.ts b/src/app/services/llm-provider/llm-provider-call.spec.ts
new file mode 100644
index 0000000..da7519b
--- /dev/null
+++ b/src/app/services/llm-provider/llm-provider-call.spec.ts
@@ -0,0 +1,33 @@
+import { provideHttpClient } from '@angular/common/http';
+import { HttpTestingController, provideHttpClientTesting } from '@angular/common/http/testing';
+import { TestBed } from '@angular/core/testing';
+import { environment } from '@environment';
+import { firstValueFrom } from 'rxjs';
+import { LlmProviderCallService } from './llm-provider-call';
+
+describe('LlmProviderCallService', () => {
+  let service: LlmProviderCallService;
+  let httpMock: HttpTestingController;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [LlmProviderCallService, provideHttpClient(), provideHttpClientTesting()]
+    });
+    service = TestBed.inject(LlmProviderCallService);
+    httpMock = TestBed.inject(HttpTestingController);
+  });
+
+  afterEach(() => httpMock.verify());
+
+  it('maps provider capabilities from the backend', async () => {
+    const result = firstValueFrom(service.listCapabilities());
+    httpMock.expectOne(`${environment.apiUrl}/llm/providers`).flush([
+      { name: 'InternalOllama', requiresCredential: false },
+      { name: 'OpenAI', requiresCredential: true }
+    ]);
+    await expect(result).resolves.toEqual([
+      { name: 'InternalOllama', requiresCredential: false },
+      { name: 'OpenAI', requiresCredential: true }
+    ]);
+  });
+});
diff --git a/src/app/services/llm-provider/llm-provider-call.ts b/src/app/services/llm-provider/llm-provider-call.ts
new file mode 100644
index 0000000..7968774
--- /dev/null
+++ b/src/app/services/llm-provider/llm-provider-call.ts
@@ -0,0 +1,25 @@
+import { HttpClient } from '@angular/common/http';
+import { inject } from '@angular/core';
+import { environment } from '@environment';
+import { LlmProviderCapability } from '@models/llm-provider';
+import { map, Observable } from 'rxjs';
+import { LlmProviderCallServiceBase } from './llm-provider-call.base';
+
+export class LlmProviderCallService extends LlmProviderCallServiceBase {
+  private readonly http = inject(HttpClient);
+
+  override listCapabilities(): Observable<LlmProviderCapability[]> {
+    return this.http.get<unknown>(`${environment.apiUrl}/llm/providers`).pipe(
+      map((raw) => {
+        if (!Array.isArray(raw)) return [];
+        return raw
+          .filter((item): item is Record<string, unknown> => !!item && typeof item === 'object')
+          .map((item) => ({
+            name: String(item['name'] ?? '').trim(),
+            requiresCredential: item['requiresCredential'] === true
+          }))
+          .filter((item) => item.name.length > 0);
+      })
+    );
+  }
+}
diff --git a/src/app/services/llm-provider/llm-provider.ts b/src/app/services/llm-provider/llm-provider.ts
new file mode 100644
index 0000000..1410b90
--- /dev/null
+++ b/src/app/services/llm-provider/llm-provider.ts
@@ -0,0 +1,14 @@
+import { Injectable } from '@angular/core';
+import { environment } from '@environment';
+import { LlmProviderCapability } from '@models/llm-provider';
+import { Observable } from 'rxjs';
+import { LlmProviderCallServiceBase } from './llm-provider-call.base';
+
+@Injectable({ providedIn: 'root' })
+export class LlmProviderService {
+  llmProviderCallService: LlmProviderCallServiceBase = new environment.llmProviderCallService();
+
+  listCapabilities(): Observable<LlmProviderCapability[]> {
+    return this.llmProviderCallService.listCapabilities();
+  }
+}
diff --git a/src/app/services/shared/http-error.util.spec.ts b/src/app/services/shared/http-error.util.spec.ts
index 048888b..85dcbb5 100644
--- a/src/app/services/shared/http-error.util.spec.ts
+++ b/src/app/services/shared/http-error.util.spec.ts
@@ -12,6 +12,7 @@ describe('extractHttpErrorMessage', () => {
     expect(extractHttpErrorMessage(new HttpErrorResponse({ error: { message: 'msg' }, status: 400 }))).toBe('msg');
     expect(extractHttpErrorMessage(new HttpErrorResponse({ error: { error: 'err' }, status: 400 }))).toBe('err');
     expect(extractHttpErrorMessage(new HttpErrorResponse({ error: { details: 'det' }, status: 400 }))).toBe('det');
+    expect(extractHttpErrorMessage(new HttpErrorResponse({ error: { detail: 'problem detail' }, status: 400 }))).toBe('problem detail');
   });
 
   it('returns null when nothing usable is present', () => {
diff --git a/src/app/services/shared/http-error.util.ts b/src/app/services/shared/http-error.util.ts
index 0030ea2..0d6017e 100644
--- a/src/app/services/shared/http-error.util.ts
+++ b/src/app/services/shared/http-error.util.ts
@@ -3,7 +3,7 @@ import { Observable, throwError } from 'rxjs';
 
 /**
  * Reads a human-readable message out of a backend error body, trying the
- * conventional `message`/`error`/`details` string fields in that order.
+ * conventional `message`/`error`/`details`/`detail` string fields in that order.
  */
 export function extractHttpErrorMessage(error: HttpErrorResponse): string | null {
   const payload = error.error;
@@ -24,6 +24,11 @@ export function extractHttpErrorMessage(error: HttpErrorResponse): string | null
     if (typeof details === 'string' && details.trim().length > 0) {
       return details.trim();
     }
+    // RFC 7807 ProblemDetail, which the execution endpoints answer with.
+    const detail = record['detail'];
+    if (typeof detail === 'string' && detail.trim().length > 0) {
+      return detail.trim();
+    }
   }
   return null;
 }
diff --git a/src/app/services/vault/credential-error-messages.ts b/src/app/services/vault/credential-error-messages.ts
new file mode 100644
index 0000000..559eeb0
--- /dev/null
+++ b/src/app/services/vault/credential-error-messages.ts
@@ -0,0 +1,9 @@
+/**
+ * Copy shared by every caller that talks to a credential endpoint, so the vault
+ * and the assistant report the same statuses the same way.
+ */
+export const CREDENTIAL_ERROR_MESSAGES: Record<number, string> = {
+  400: 'The credential is invalid, inactive, or not compatible with the selected provider.',
+  401: 'You must sign in to use or manage credentials.',
+  409: 'This provider does not support user credentials.'
+};
diff --git a/src/app/services/vault/vault-call.base.ts b/src/app/services/vault/vault-call.base.ts
new file mode 100644
index 0000000..a613e92
--- /dev/null
+++ b/src/app/services/vault/vault-call.base.ts
@@ -0,0 +1,31 @@
+import { VaultSecret, VaultSecretCreateRequest, VaultSecretUpdateRequest } from '@models/assistant';
+import { Observable } from 'rxjs';
+
+export abstract class VaultCallServiceBase {
+  abstract listSecrets(): Observable<VaultSecret[]>;
+  abstract createSecret(request: VaultSecretCreateRequest): Observable<VaultSecret>;
+  abstract updateSecret(id: string, request: VaultSecretUpdateRequest): Observable<VaultSecret>;
+  abstract deleteSecret(id: string): Observable<void>;
+}
+
+export function mapVaultSecrets(raw: unknown): VaultSecret[] {
+  const items = Array.isArray(raw)
+    ? raw
+    : raw && typeof raw === 'object'
+      ? ((raw as Record<string, unknown>)['items'] ?? (raw as Record<string, unknown>)['values'] ?? [])
+      : [];
+  return Array.isArray(items) ? items.map(mapVaultSecret).filter((item) => !!item.id) : [];
+}
+
+export function mapVaultSecret(raw: unknown): VaultSecret {
+  const value = (raw && typeof raw === 'object' ? raw : {}) as Record<string, unknown>;
+  return {
+    id: String(value['id'] ?? value['secretId'] ?? ''),
+    label: String(value['label'] ?? ''),
+    provider: String(value['provider'] ?? ''),
+    description: typeof value['description'] === 'string' ? value['description'] : undefined,
+    active: value['active'] !== false && value['enabled'] !== false,
+    lastUsedAt: typeof value['lastUsedAt'] === 'string' ? value['lastUsedAt'] : undefined,
+    maskedPreview: typeof value['maskedPreview'] === 'string' ? value['maskedPreview'] : undefined
+  };
+}
diff --git a/src/app/services/vault/vault-call.fake.ts b/src/app/services/vault/vault-call.fake.ts
new file mode 100644
index 0000000..7b8f386
--- /dev/null
+++ b/src/app/services/vault/vault-call.fake.ts
@@ -0,0 +1,28 @@
+import { VaultSecret, VaultSecretCreateRequest, VaultSecretUpdateRequest } from '@models/assistant';
+import { Observable, of, throwError } from 'rxjs';
+import { VaultCallServiceBase } from './vault-call.base';
+import { vaultFakeStore } from './vault-fake-store';
+
+export class VaultCallServiceFake extends VaultCallServiceBase {
+  override listSecrets(): Observable<VaultSecret[]> {
+    return of(vaultFakeStore.list());
+  }
+
+  override createSecret(request: VaultSecretCreateRequest): Observable<VaultSecret> {
+    if (!request.value.trim()) return throwError(() => new Error('The credential value is required.'));
+    return of(vaultFakeStore.create(request));
+  }
+
+  override updateSecret(id: string, request: VaultSecretUpdateRequest): Observable<VaultSecret> {
+    try {
+      return of(vaultFakeStore.update(id, request));
+    } catch (error) {
+      return throwError(() => error);
+    }
+  }
+
+  override deleteSecret(id: string): Observable<void> {
+    vaultFakeStore.remove(id);
+    return of(void 0);
+  }
+}
diff --git a/src/app/services/vault/vault-call.spec.ts b/src/app/services/vault/vault-call.spec.ts
new file mode 100644
index 0000000..8c62c87
--- /dev/null
+++ b/src/app/services/vault/vault-call.spec.ts
@@ -0,0 +1,66 @@
+import { provideHttpClient } from '@angular/common/http';
+import { HttpTestingController, provideHttpClientTesting } from '@angular/common/http/testing';
+import { TestBed } from '@angular/core/testing';
+import { environment } from '@environment';
+import { firstValueFrom } from 'rxjs';
+import { CREDENTIAL_ERROR_MESSAGES } from './credential-error-messages';
+import { VaultCallService } from './vault-call';
+
+describe('VaultCallService', () => {
+  let service: VaultCallService;
+  let httpMock: HttpTestingController;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [VaultCallService, provideHttpClient(), provideHttpClientTesting()]
+    });
+    service = TestBed.inject(VaultCallService);
+    httpMock = TestBed.inject(HttpTestingController);
+  });
+
+  afterEach(() => httpMock.verify());
+
+  it('maps secret metadata without exposing a value', async () => {
+    const result = firstValueFrom(service.listSecrets());
+    httpMock.expectOne(`${environment.apiUrl}/vault/secrets`).flush([{
+      id: 'credential-1',
+      label: 'OpenAI key',
+      provider: 'OpenAI',
+      active: true,
+      maskedPreview: '***',
+      value: 'must-not-reach-the-ui'
+    }]);
+
+    await expect(result).resolves.toEqual([{
+      id: 'credential-1',
+      label: 'OpenAI key',
+      provider: 'OpenAI',
+      active: true,
+      maskedPreview: '***'
+    }]);
+  });
+
+  it('sends a value only on explicit create or rotation requests', async () => {
+    const create = firstValueFrom(service.createSecret({
+      label: 'OpenAI key', provider: 'OpenAI', value: 'secret-value'
+    }));
+    const createRequest = httpMock.expectOne(`${environment.apiUrl}/vault/secrets`);
+    expect(createRequest.request.body).toEqual({ label: 'OpenAI key', provider: 'OpenAI', value: 'secret-value' });
+    createRequest.flush({ id: 'credential-1', label: 'OpenAI key', provider: 'OpenAI', active: true });
+    await create;
+
+    const update = firstValueFrom(service.updateSecret('credential-1', { value: 'rotated-value' }));
+    const updateRequest = httpMock.expectOne(`${environment.apiUrl}/vault/secrets/credential-1`);
+    expect(updateRequest.request.body).toEqual({ value: 'rotated-value' });
+    updateRequest.flush({ id: 'credential-1', label: 'OpenAI key', provider: 'OpenAI', active: true });
+    await update;
+  });
+
+  it('falls back to the shared credential message when the backend sends no body', async () => {
+    const result = firstValueFrom(service.deleteSecret('credential-1'));
+    httpMock.expectOne(`${environment.apiUrl}/vault/secrets/credential-1`)
+      .flush(null, { status: 409, statusText: 'Conflict' });
+
+    await expect(result).rejects.toThrow(CREDENTIAL_ERROR_MESSAGES[409]);
+  });
+});
diff --git a/src/app/services/vault/vault-call.ts b/src/app/services/vault/vault-call.ts
new file mode 100644
index 0000000..f08d743
--- /dev/null
+++ b/src/app/services/vault/vault-call.ts
@@ -0,0 +1,47 @@
+import { HttpClient } from '@angular/common/http';
+import { inject } from '@angular/core';
+import { environment } from '@environment';
+import { VaultSecret, VaultSecretCreateRequest, VaultSecretUpdateRequest } from '@models/assistant';
+import { extractHttpErrorMessage } from '@services/shared/http-error.util';
+import { catchError, map, Observable, throwError } from 'rxjs';
+import { CREDENTIAL_ERROR_MESSAGES } from './credential-error-messages';
+import { mapVaultSecret, mapVaultSecrets, VaultCallServiceBase } from './vault-call.base';
+
+export class VaultCallService extends VaultCallServiceBase {
+  private readonly http = inject(HttpClient);
+
+  override listSecrets(): Observable<VaultSecret[]> {
+    return this.http.get<unknown>(`${environment.apiUrl}/vault/secrets`).pipe(
+      map((raw) => mapVaultSecrets(raw)),
+      catchError((error: unknown) => this.vaultError(error))
+    );
+  }
+
+  override createSecret(request: VaultSecretCreateRequest): Observable<VaultSecret> {
+    return this.http.post<unknown>(`${environment.apiUrl}/vault/secrets`, request).pipe(
+      map((raw) => mapVaultSecret(raw)),
+      catchError((error: unknown) => this.vaultError(error))
+    );
+  }
+
+  override updateSecret(id: string, request: VaultSecretUpdateRequest): Observable<VaultSecret> {
+    return this.http.put<unknown>(`${environment.apiUrl}/vault/secrets/${encodeURIComponent(id)}`, request).pipe(
+      map((raw) => mapVaultSecret(raw)),
+      catchError((error: unknown) => this.vaultError(error))
+    );
+  }
+
+  override deleteSecret(id: string): Observable<void> {
+    return this.http.delete<void>(`${environment.apiUrl}/vault/secrets/${encodeURIComponent(id)}`).pipe(
+      catchError((error: unknown) => this.vaultError(error))
+    );
+  }
+
+  private vaultError(error: unknown): Observable<never> {
+    const response = error as { status?: unknown; error?: unknown };
+    const message = extractHttpErrorMessage(response as any)
+      ?? CREDENTIAL_ERROR_MESSAGES[Number(response?.status)]
+      ?? 'Unable to update provider credentials.';
+    return throwError(() => new Error(message));
+  }
+}
diff --git a/src/app/services/vault/vault-fake-store.spec.ts b/src/app/services/vault/vault-fake-store.spec.ts
new file mode 100644
index 0000000..ac1c738
--- /dev/null
+++ b/src/app/services/vault/vault-fake-store.spec.ts
@@ -0,0 +1,32 @@
+import { ExecutionVaultCredentialsCallServiceFake } from '@services/llm-provider/execution-vault-credentials-call.fake';
+import { firstValueFrom } from 'rxjs';
+import { VaultCallServiceFake } from './vault-call.fake';
+import { vaultFakeStore } from './vault-fake-store';
+
+describe('vault fake store', () => {
+  const vault = new VaultCallServiceFake();
+  const credentials = new ExecutionVaultCredentialsCallServiceFake();
+
+  it('offers only active credentials of the requested provider to an execution', async () => {
+    const listed = await firstValueFrom(credentials.listForProvider('testProvider'));
+
+    expect(listed.map((item) => item.id)).toEqual([
+      'vault-secret-testprovider-1',
+      'vault-secret-testprovider-2'
+    ]);
+    expect(vaultFakeStore.list().some((secret) => !secret.active)).toBe(true);
+  });
+
+  it('shows a credential created through the vault in the execution picker', async () => {
+    const created = await firstValueFrom(vault.createSecret({
+      label: 'testProvider - fresh key', provider: 'testProvider', value: 'sk-brand-new'
+    }));
+    const listed = await firstValueFrom(credentials.listForProvider('testProvider'));
+
+    expect(listed.map((item) => item.id)).toContain(created.id);
+
+    await firstValueFrom(vault.deleteSecret(created.id));
+    const afterDelete = await firstValueFrom(credentials.listForProvider('testProvider'));
+    expect(afterDelete.map((item) => item.id)).not.toContain(created.id);
+  });
+});
diff --git a/src/app/services/vault/vault-fake-store.ts b/src/app/services/vault/vault-fake-store.ts
new file mode 100644
index 0000000..1afbd57
--- /dev/null
+++ b/src/app/services/vault/vault-fake-store.ts
@@ -0,0 +1,85 @@
+import { VaultSecret, VaultSecretCreateRequest, VaultSecretUpdateRequest } from '@models/assistant';
+
+/**
+ * In-memory vault shared by the fake call services, so a credential created from
+ * the assistant panel shows up in the execution credential picker, exactly as it
+ * does against the real backend.
+ */
+class VaultFakeStore {
+  private sequence = 0;
+  private readonly secrets: VaultSecret[] = [
+    {
+      id: 'vault-secret-testprovider-1',
+      label: 'testProvider - team key',
+      provider: 'testProvider',
+      description: 'Shared key for the demo workspace',
+      active: true,
+      maskedPreview: 'sk-...4f2a'
+    },
+    {
+      id: 'vault-secret-testprovider-2',
+      label: 'testProvider - personal key',
+      provider: 'testProvider',
+      active: true,
+      maskedPreview: 'sk-...91cd'
+    },
+    {
+      id: 'vault-secret-testprovider-3',
+      label: 'testProvider - revoked key',
+      provider: 'testProvider',
+      description: 'Disabled, never offered to an execution',
+      active: false,
+      maskedPreview: 'sk-...0007'
+    },
+    {
+      id: 'vault-secret-gemini-1',
+      label: 'Gemini - default key',
+      provider: 'Gemini',
+      active: true,
+      maskedPreview: 'AI...b31'
+    }
+  ];
+
+  list(): VaultSecret[] {
+    return this.secrets.map((secret) => ({ ...secret }));
+  }
+
+  /** Mirrors the server-side filter of the credential listing: owner, active, provider. */
+  listActiveByProvider(provider: string): VaultSecret[] {
+    const wanted = provider.trim().toLowerCase();
+    return this.secrets
+      .filter((secret) => secret.active && secret.provider.trim().toLowerCase() === wanted)
+      .map((secret) => ({ ...secret }));
+  }
+
+  create(request: VaultSecretCreateRequest): VaultSecret {
+    const created: VaultSecret = {
+      id: `vault-secret-created-${++this.sequence}`,
+      label: request.label,
+      provider: request.provider,
+      description: request.description,
+      active: true,
+      maskedPreview: `${request.value.slice(0, 2)}...${request.value.slice(-3)}`
+    };
+    this.secrets.push(created);
+    return { ...created };
+  }
+
+  update(id: string, request: VaultSecretUpdateRequest): VaultSecret {
+    const secret = this.secrets.find((item) => item.id === id);
+    if (!secret) throw new Error('The credential no longer exists.');
+    if (request.label !== undefined) secret.label = request.label;
+    if (request.description !== undefined) secret.description = request.description;
+    if (request.active !== undefined) secret.active = request.active;
+    if (request.value) secret.maskedPreview = `${request.value.slice(0, 2)}...${request.value.slice(-3)}`;
+    return { ...secret };
+  }
+
+  /** The backend soft-deletes, so the secret stays but stops being offered. */
+  remove(id: string): void {
+    const secret = this.secrets.find((item) => item.id === id);
+    if (secret) secret.active = false;
+  }
+}
+
+export const vaultFakeStore = new VaultFakeStore();
diff --git a/src/app/services/vault/vault.ts b/src/app/services/vault/vault.ts
new file mode 100644
index 0000000..52fdbc5
--- /dev/null
+++ b/src/app/services/vault/vault.ts
@@ -0,0 +1,28 @@
+import { Injectable } from '@angular/core';
+import { environment } from '@environment';
+import { VaultSecret, VaultSecretCreateRequest, VaultSecretUpdateRequest } from '@models/assistant';
+import { Observable } from 'rxjs';
+import { VaultCallServiceBase } from './vault-call.base';
+
+export { CREDENTIAL_ERROR_MESSAGES } from './credential-error-messages';
+
+@Injectable({ providedIn: 'root' })
+export class VaultService {
+  vaultCallService: VaultCallServiceBase = new environment.vaultCallService();
+
+  listSecrets(): Observable<VaultSecret[]> {
+    return this.vaultCallService.listSecrets();
+  }
+
+  createSecret(request: VaultSecretCreateRequest): Observable<VaultSecret> {
+    return this.vaultCallService.createSecret(request);
+  }
+
+  updateSecret(id: string, request: VaultSecretUpdateRequest): Observable<VaultSecret> {
+    return this.vaultCallService.updateSecret(id, request);
+  }
+
+  deleteSecret(id: string): Observable<void> {
+    return this.vaultCallService.deleteSecret(id);
+  }
+}
diff --git a/src/environments/environment.development.ts b/src/environments/environment.development.ts
index 551bbc5..e6c44e9 100644
--- a/src/environments/environment.development.ts
+++ b/src/environments/environment.development.ts
@@ -3,6 +3,9 @@ import { AssistantCallServiceFake } from "@services/assistant/assistant-call.fak
 import { AuthorizationCallFakeService } from "@services/authorization/authorization-call.fake";
 import { BlocksCallServiceFake } from "@services/blocks/blocks-call.fake";
 import { ContainersCallServiceFake } from "@services/containers/containers-call.fake";
+import { ExecutionVaultCredentialsCallServiceFake } from "@services/llm-provider/execution-vault-credentials-call.fake";
+import { LlmProviderCallServiceFake } from "@services/llm-provider/llm-provider-call.fake";
+import { VaultCallServiceFake } from "@services/vault/vault-call.fake";
 import { FlowsCallServiceFake } from "@services/flows/flows-call.fake";
 import { FieldRetrieverCallServiceFake } from "@services/retriever/field-retriever-call.fake";
 import { TaskExecutionsCallServiceFake } from "@services/task-executions/task-executions-call.fake";
@@ -20,5 +23,8 @@ export const environment = {
     blocksCallService: BlocksCallServiceFake,
     containersCallService: ContainersCallServiceFake,
     fieldRetrieverCallService: FieldRetrieverCallServiceFake,
-    taskExecutionsCallService: TaskExecutionsCallServiceFake
+    taskExecutionsCallService: TaskExecutionsCallServiceFake,
+    llmProviderCallService: LlmProviderCallServiceFake,
+    executionVaultCredentialsCallService: ExecutionVaultCredentialsCallServiceFake,
+    vaultCallService: VaultCallServiceFake
 };
diff --git a/src/environments/environment.staging.ts b/src/environments/environment.staging.ts
index ebefc40..fe1775a 100644
--- a/src/environments/environment.staging.ts
+++ b/src/environments/environment.staging.ts
@@ -3,6 +3,9 @@ import { AssistantCallService } from "@services/assistant/assistant-call";
 import { AuthorizationCallService } from "@services/authorization/authorization-call";
 import { BlocksCallService } from "@services/blocks/blocks-call";
 import { ContainersCallService } from "@services/containers/containers-call";
+import { ExecutionVaultCredentialsCallService } from "@services/llm-provider/execution-vault-credentials-call";
+import { LlmProviderCallService } from "@services/llm-provider/llm-provider-call";
+import { VaultCallService } from "@services/vault/vault-call";
 import { FlowsCallService } from "@services/flows/flows-call";
 import { FieldRetrieverCallService } from "@services/retriever/field-retriever-call";
 import { TaskExecutionsCallService } from "@services/task-executions/task-executions-call";
@@ -20,5 +23,8 @@ export const environment = {
     blocksCallService: BlocksCallService,
     containersCallService: ContainersCallService,
     fieldRetrieverCallService: FieldRetrieverCallService,
-    taskExecutionsCallService: TaskExecutionsCallService
+    taskExecutionsCallService: TaskExecutionsCallService,
+    llmProviderCallService: LlmProviderCallService,
+    executionVaultCredentialsCallService: ExecutionVaultCredentialsCallService,
+    vaultCallService: VaultCallService
 };
diff --git a/src/environments/environment.ts b/src/environments/environment.ts
index 1af1474..bfd98a8 100644
--- a/src/environments/environment.ts
+++ b/src/environments/environment.ts
@@ -3,6 +3,9 @@ import { AssistantCallService } from "@services/assistant/assistant-call";
 import { AuthorizationCallService } from "@services/authorization/authorization-call";
 import { BlocksCallService } from "@services/blocks/blocks-call";
 import { ContainersCallService } from "@services/containers/containers-call";
+import { ExecutionVaultCredentialsCallService } from "@services/llm-provider/execution-vault-credentials-call";
+import { LlmProviderCallService } from "@services/llm-provider/llm-provider-call";
+import { VaultCallService } from "@services/vault/vault-call";
 import { FlowsCallService } from "@services/flows/flows-call";
 import { FieldRetrieverCallService } from "@services/retriever/field-retriever-call";
 import { TaskExecutionsCallService } from "@services/task-executions/task-executions-call";
@@ -20,5 +23,8 @@ export const environment = {
         blocksCallService: BlocksCallService,
         containersCallService: ContainersCallService,
         fieldRetrieverCallService: FieldRetrieverCallService,
-        taskExecutionsCallService: TaskExecutionsCallService
+        taskExecutionsCallService: TaskExecutionsCallService,
+        llmProviderCallService: LlmProviderCallService,
+        executionVaultCredentialsCallService: ExecutionVaultCredentialsCallService,
+        vaultCallService: VaultCallService
 };