diff --git a/packages/shared/src/providers/connection.ts b/packages/shared/src/providers/connection.ts
index 73e2dbe..add4958 100644
--- a/packages/shared/src/providers/connection.ts
+++ b/packages/shared/src/providers/connection.ts
@@ -1,6 +1,20 @@
 import type { FinancialProviderStatus, ProviderRoutingConfig } from '@finagent/core';
 import type { JsonFileStore } from '../storage/json-file-store.ts';
 
+/**
+ * Strip URL userinfo credentials (`scheme://user:pass@host`) from an
+ * endpoint before it reaches disk or the UI (issue #93). `ProviderConfig`
+ * is the non-secret settings channel — credentials belong in the OS-backed
+ * CredentialStore — and userinfo is a credential shape. Scheme, host and
+ * path are preserved so the endpoint stays readable; hosts without
+ * userinfo pass through untouched.
+ */
+const ENDPOINT_USERINFO = /(^[a-z][a-z0-9+.-]*:\/\/)[^/@\s]+@/i;
+
+export function sanitizeEndpoint(endpoint: string): string {
+  return endpoint.replace(ENDPOINT_USERINFO, '$1[REDACTED]@');
+}
+
 /**
  * Connection lifecycle state for ONE provider (spec §8). Provider-agnostic:
  * any financial-data or broker-account provider records the same shape.
@@ -69,7 +83,14 @@ export class ConnectionStore {
 
   async getConfig(providerId: string): Promise<ProviderConfig | undefined> {
     const file = await this.store.read<ConnectionsFile>(ConnectionStore.FILE, { connections: [] });
-    return file.configs?.[providerId];
+    const config = file.configs?.[providerId];
+    // Lazy sanitization: files written before issue #93 may still carry
+    // cleartext userinfo in endpoints — never surface it, even at rest.
+    if (!config) return config;
+    return {
+      ...config,
+      endpoint: config.endpoint !== undefined ? sanitizeEndpoint(config.endpoint) : undefined,
+    };
   }
 
   async setConfig(providerId: string, config: ProviderConfig): Promise<void> {
@@ -77,9 +98,10 @@ export class ConnectionStore {
     const configs = { ...(file.configs ?? {}) };
     // Copy only the allowlisted non-secret fields. This prevents accidental
     // credential persistence even when an untyped caller supplies apiKey.
+    // Endpoints additionally lose userinfo credentials (issue #93).
     configs[providerId] = {
       enabled: config.enabled,
-      endpoint: config.endpoint,
+      endpoint: config.endpoint !== undefined ? sanitizeEndpoint(config.endpoint) : undefined,
       region: config.region,
     };
     await this.store.write(ConnectionStore.FILE, { ...file, configs });
diff --git a/packages/shared/src/providers/providers.test.ts b/packages/shared/src/providers/providers.test.ts
index a08649d..be94432 100644
--- a/packages/shared/src/providers/providers.test.ts
+++ b/packages/shared/src/providers/providers.test.ts
@@ -453,6 +453,51 @@ describe('ConnectionStore', () => {
     const raw = await store.read<Record<string, unknown>>('connections.json', {});
     expect(JSON.stringify(raw)).not.toContain('canary-secret-123');
   });
+
+  it('persists endpoints without cleartext userinfo credentials (issue #93)', async () => {
+    const connections = new ConnectionStore(store);
+    await connections.setConfig('massive', {
+      enabled: true,
+      endpoint: 'https://folio_user:sup3rsecret@db.host.internal:5432/api',
+    });
+
+    // At-rest file must not carry the password.
+    const raw = await store.read<Record<string, unknown>>('connections.json', {});
+    expect(JSON.stringify(raw)).not.toContain('sup3rsecret');
+    expect(JSON.stringify(raw)).not.toContain('folio_user:');
+    // Host/path survive so the target stays readable.
+    expect(JSON.stringify(raw)).toContain('db.host.internal:5432/api');
+    expect(JSON.stringify(raw)).toContain('[REDACTED]');
+
+    // Read side never surfaces the credential either.
+    const config = await connections.getConfig('massive');
+    expect(config?.endpoint).toBe('https://[REDACTED]@db.host.internal:5432/api');
+  });
+
+  it('sanitizes legacy cleartext-userinfo configs on read (issue #93)', async () => {
+    // Simulate a file written before the fix.
+    await store.write('connections.json', {
+      connections: [],
+      configs: {
+        massive: { enabled: true, endpoint: 'https://user:legacy-pass@old.host/api' },
+      },
+    });
+    const connections = new ConnectionStore(store);
+    expect((await connections.getConfig('massive'))?.endpoint).toBe(
+      'https://[REDACTED]@old.host/api'
+    );
+  });
+
+  it('leaves endpoints without userinfo untouched (issue #93)', async () => {
+    const connections = new ConnectionStore(store);
+    await connections.setConfig('massive', {
+      enabled: true,
+      endpoint: 'https://api.example.com/v1?symbol=AAPL',
+    });
+    expect((await connections.getConfig('massive'))?.endpoint).toBe(
+      'https://api.example.com/v1?symbol=AAPL'
+    );
+  });
 });
 
 describe('createRouterFetchers', () => {