feat: add Tess runtime provider registry (#722)

packages/agent/src/runtime-provider-registry.test.ts

@@ -0,0 +1,95 @@
+import { describe, expect, it } from 'vitest';
+import type {
+  AgentRuntimeProvider,
+  RuntimeAttachHandle,
+  RuntimeAttachMode,
+  RuntimeCapabilitySet,
+  RuntimeHealth,
+  RuntimeMessage,
+  RuntimeScope,
+  RuntimeSession,
+  RuntimeSessionTree,
+  RuntimeStreamEvent,
+} from '@mosaicstack/types';
+import { AgentRuntimeProviderRegistry } from './runtime-provider-registry.js';
+
+class TestRuntimeProvider implements AgentRuntimeProvider {
+  readonly id = 'test-runtime';
+
+  async capabilities(_scope: RuntimeScope): Promise<RuntimeCapabilitySet> {
+    return { supported: ['session.list'] };
+  }
+
+  async health(_scope: RuntimeScope): Promise<RuntimeHealth> {
+    return { status: 'healthy', checkedAt: '2026-07-12T00:00:00.000Z' };
+  }
+
+  async listSessions(_scope: RuntimeScope): Promise<RuntimeSession[]> {
+    return [];
+  }
+
+  async getSessionTree(_scope: RuntimeScope): Promise<RuntimeSessionTree[]> {
+    return [];
+  }
+
+  async *streamSession(
+    _sessionId: string,
+    _cursor: string | undefined,
+    _scope: RuntimeScope,
+  ): AsyncIterable<RuntimeStreamEvent> {
+    return;
+  }
+
+  async sendMessage(
+    _sessionId: string,
+    _message: RuntimeMessage,
+    _scope: RuntimeScope,
+  ): Promise<void> {}
+
+  async attach(
+    _sessionId: string,
+    _mode: RuntimeAttachMode,
+    _scope: RuntimeScope,
+  ): Promise<RuntimeAttachHandle> {
+    return {
+      attachmentId: 'attachment-1',
+      sessionId: 'session-1',
+      mode: 'read',
+      expiresAt: '2026-07-12T00:00:00.000Z',
+    };
+  }
+
+  async detach(_attachmentId: string, _scope: RuntimeScope): Promise<void> {}
+
+  async terminate(_sessionId: string, _approvalRef: string, _scope: RuntimeScope): Promise<void> {}
+}
+
+describe('AgentRuntimeProviderRegistry', (): void => {
+  it('resolves only registered runtime providers', (): void => {
+    const registry = new AgentRuntimeProviderRegistry();
+    const provider = new TestRuntimeProvider();
+
+    registry.register(provider);
+
+    expect(registry.get(provider.id)).toBe(provider);
+    expect(registry.get('unknown-runtime')).toBeUndefined();
+    expect(registry.list()).toEqual([provider]);
+  });
+
+  it('rejects duplicate and blank provider identities rather than silently replacing a runtime', (): void => {
+    const registry = new AgentRuntimeProviderRegistry();
+    const provider = new TestRuntimeProvider();
+
+    registry.register(provider);
+
+    expect((): void => {
+      registry.register(provider);
+    }).toThrow(/already registered/);
+    expect((): void => {
+      registry.require('');
+    }).toThrow(/provider ID is required/);
+    expect((): void => {
+      registry.require('unknown-runtime');
+    }).toThrow(/not registered/);
+  });
+});