feat: Added openrouter provider

package.json

@@ -47,6 +47,7 @@
   },
   "dependencies": {
     "@langchain/google-genai": "^2.2.0",
+    "@langchain/openrouter": "^0.4.3",
     "@types/node": "^20.19.43",
     "dotenv": "^17.4.2"
   }

packages/llm/src/config.ts

@@ -2,6 +2,7 @@ import { z } from "zod";
 
 const LLMConfigSchema = z.object({
   GOOGLE_API_KEY: z.string().optional(),
+  OPENROUTER_API_KEY: z.string().optional(),
 });
 
 export const llmConfig = LLMConfigSchema.parse(process.env);

packages/llm/src/index.ts

@@ -2,3 +2,4 @@ export * from "./llm.js";
 export * from "./config.js";
 export * from "./providers/google-genai.js";
 export * from "./providers/mock.js";
+export * from "./providers/openrouter.js";

packages/llm/src/providers/openrouter.ts

@@ -0,0 +1,31 @@
+import { z } from "zod";
+import { ChatOpenRouter } from "@langchain/openrouter";
+import { ILLMProvider, LLMRequest, LLMResponse } from "../llm.js";
+import { llmConfig } from "../config.js";
+
+export class OpenRouterProvider implements ILLMProvider {
+  providerName = "OpenRouter";
+  private model: ChatOpenRouter;
+
+  constructor(apiKey?: string, modelName: string = "google/gemini-2.5-flash") {
+    const key = apiKey || llmConfig.OPENROUTER_API_KEY;
+    if (!key) {
+      throw new Error("OPENROUTER_API_KEY is required to initialize OpenRouterProvider");
+    }
+    this.model = new ChatOpenRouter({
+      apiKey: key,
+      model: modelName,
+    });
+  }
+
+  async generateStructuredResponse<T extends z.ZodTypeAny>(
+    request: LLMRequest<T>,
+  ): Promise<LLMResponse<z.infer<T>>> {
+    const structuredModel = this.model.withStructuredOutput(request.schema);
+    const result = await structuredModel.invoke([
+      { role: "system", content: request.systemPrompt },
+      { role: "user", content: request.userContext },
+    ]);
+    return { success: true, data: result as z.infer<T> };
+  }
+}

packages/llm/tests/openrouter.test.ts

@@ -0,0 +1,81 @@
+import { describe, test, expect, vi } from "vitest";
+import { z } from "zod";
+import { OpenRouterProvider } from "../src/providers/openrouter.js";
+import { llmConfig } from "../src/config.js";
+
+// Mock the ChatOpenRouter class
+vi.mock("@langchain/openrouter", () => {
+  return {
+    ChatOpenRouter: class {
+      config: unknown;
+      constructor(config: unknown) {
+        this.config = config;
+      }
+      withStructuredOutput = vi.fn().mockImplementation(() => {
+        return {
+          invoke: vi.fn().mockImplementation(async () => {
+            // Return a mock output that matches a sample schema
+            return {
+              name: "mocked response",
+              success: true,
+            };
+          }),
+        };
+      });
+    },
+  };
+});
+
+describe("OpenRouterProvider Unit Tests (Tier 1)", () => {
+  test("initializes successfully with a provided apiKey", () => {
+    const provider = new OpenRouterProvider("dummy-key");
+    expect(provider.providerName).toBe("OpenRouter");
+  });
+
+  test("initializes successfully with apiKey from config", () => {
+    // Save current config
+    const originalKey = llmConfig.OPENROUTER_API_KEY;
+    llmConfig.OPENROUTER_API_KEY = "env-dummy-key";
+    
+    try {
+      const provider = new OpenRouterProvider();
+      expect(provider.providerName).toBe("OpenRouter");
+    } finally {
+      llmConfig.OPENROUTER_API_KEY = originalKey;
+    }
+  });
+
+  test("throws error if no API key is provided or in config", () => {
+    // Save current config
+    const originalKey = llmConfig.OPENROUTER_API_KEY;
+    llmConfig.OPENROUTER_API_KEY = undefined;
+
+    try {
+      expect(() => new OpenRouterProvider()).toThrow(
+        "OPENROUTER_API_KEY is required to initialize OpenRouterProvider"
+      );
+    } finally {
+      llmConfig.OPENROUTER_API_KEY = originalKey;
+    }
+  });
+
+  test("generateStructuredResponse invokes the model with structured output", async () => {
+    const provider = new OpenRouterProvider("dummy-key");
+    const TestSchema = z.object({
+      name: z.string(),
+      success: z.boolean(),
+    });
+
+    const response = await provider.generateStructuredResponse({
+      systemPrompt: "system prompt",
+      userContext: "user context",
+      schema: TestSchema,
+    });
+
+    expect(response.success).toBe(true);
+    expect(response.data).toEqual({
+      name: "mocked response",
+      success: true,
+    });
+  });
+});

pnpm-lock.yaml

@@ -209,7 +209,10 @@ importers:
     dependencies:
       '@langchain/google-genai':
         specifier: ^2.2.0
-        version: 2.2.0(@langchain/core@1.2.1)
+        version: 2.2.0(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))
+      '@langchain/openrouter':
+        specifier: ^0.4.3
+        version: 0.4.3(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))(zod@4.4.3)
       '@types/node':
         specifier: ^20.19.43
         version: 20.19.43
@@ -376,7 +379,7 @@ importers:
     dependencies:
       '@langchain/google-genai':
         specifier: ^2.2.0
-        version: 2.2.0(@langchain/core@1.2.1)
+        version: 2.2.0(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))
       '@types/node':
         specifier: ^26.1.0
         version: 26.1.0
@@ -1259,6 +1262,18 @@ packages:
     peerDependencies:
       '@langchain/core': ^1.2.0
 
+  '@langchain/openai@1.5.3':
+    resolution: {integrity: sha512-OStS2AUvy9oe/hEf/3ndBOFztUDOfuJYLNXh89m3iiJAI2Cp5Dp0n/pvpO27MO0b+VgENd+xSHVyQZ7fe+ulxg==}
+    engines: {node: '>=20'}
+    peerDependencies:
+      '@langchain/core': ^1.2.1
+
+  '@langchain/openrouter@0.4.3':
+    resolution: {integrity: sha512-LUul0i3VAlQBkhOg0EH1N20DUOxHGAZ1gqQtX1IRO/jYbDL3HZ7uHUupjMnerDaULiyAJZT3DxDw6Cr1QMT4ng==}
+    engines: {node: '>=20'}
+    peerDependencies:
+      '@langchain/core': ^1.0.0
+
   '@mdx-js/mdx@3.1.1':
     resolution: {integrity: sha512-f6ZO2ifpwAQIpzGWaBQT2TXxPv6z3RBzQKpVftEWN78Vl/YweF1uwussDx8ECAXVtr3Rs89fKyG9YlzUs9DyGQ==}
 
@@ -2584,6 +2599,10 @@ packages:
   eventemitter3@5.0.4:
     resolution: {integrity: sha512-mlsTRyGaPBjPedk6Bvw+aqbsXDtoAyAzm5MO7JgU+yVRyMQ5O8bD4Kcci7BS85f93veegeCPkL8R4GLClnjLFw==}
 
+  eventsource-parser@3.1.0:
+    resolution: {integrity: sha512-kJezFj9YFAMLeORyi7aCLxLbD5/qWMQnoMVlVPyHIll7lgRJCc3JVln9Vgl9nwQi0YkMnhdGTMNn7CkRRAptMg==}
+    engines: {node: '>=18.0.0'}
+
   expand-template@2.0.3:
     resolution: {integrity: sha512-XYfuKMvj4O35f/pOXLObndIRvyQ+/+6AhODh+OKWj9S9498pHHn/IMszH+gt0fBCRWMNfk1ZSp5x3AifmnI2vg==}
     engines: {node: '>=6'}
@@ -3561,6 +3580,26 @@ packages:
   oniguruma-to-es@4.3.6:
     resolution: {integrity: sha512-csuQ9x3Yr0cEIs/Zgx/OEt9iBw9vqIunAPQkx19R/fiMq2oGVTgcMqO/V3Ybqefr1TBvosI6jU539ksaBULJyA==}
 
+  openai@6.45.0:
+    resolution: {integrity: sha512-5DQVNErssk0afNpTTHUm/qZPU4iKR9OYdNid8Ib4puq4gHNNvGWZht2zY4h9a8JMF949Ik6m8gQutllVPbjdnw==}
+    peerDependencies:
+      '@aws-sdk/credential-provider-node': '>=3.972.0 <4'
+      '@smithy/hash-node': '>=4.3.0 <5'
+      '@smithy/signature-v4': '>=5.4.0 <6'
+      ws: ^8.18.0
+      zod: ^3.25 || ^4.0
+    peerDependenciesMeta:
+      '@aws-sdk/credential-provider-node':
+        optional: true
+      '@smithy/hash-node':
+        optional: true
+      '@smithy/signature-v4':
+        optional: true
+      ws:
+        optional: true
+      zod:
+        optional: true
+
   optionator@0.9.4:
     resolution: {integrity: sha512-6IpQ7mKUxRcZNLIObR0hz7lxsapSSIYNZJwXPGeF0mTVqGKFIXj1DQcMoT22S3ROcLyY/rz0PWaWZ9ayWmad9g==}
     engines: {node: '>= 0.8.0'}
@@ -5205,12 +5244,12 @@ snapshots:
       '@jridgewell/resolve-uri': 3.1.2
       '@jridgewell/sourcemap-codec': 1.5.5
 
-  '@langchain/core@1.2.1':
+  '@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3))':
     dependencies:
       '@cfworker/json-schema': 4.1.1
       '@standard-schema/spec': 1.1.0
       js-tiktoken: 1.0.21
-      langsmith: 0.7.15
+      langsmith: 0.7.15(openai@6.45.0(zod@4.4.3))
       mustache: 4.2.0
       p-queue: 6.6.2
       zod: 4.4.3
@@ -5221,10 +5260,35 @@ snapshots:
       - openai
       - ws
 
-  '@langchain/google-genai@2.2.0(@langchain/core@1.2.1)':
+  '@langchain/google-genai@2.2.0(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))':
     dependencies:
       '@google/generative-ai': 0.24.1
-      '@langchain/core': 1.2.1
+      '@langchain/core': 1.2.1(openai@6.45.0(zod@4.4.3))
+
+  '@langchain/openai@1.5.3(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))':
+    dependencies:
+      '@langchain/core': 1.2.1(openai@6.45.0(zod@4.4.3))
+      js-tiktoken: 1.0.21
+      openai: 6.45.0(zod@4.4.3)
+      zod: 4.4.3
+    transitivePeerDependencies:
+      - '@aws-sdk/credential-provider-node'
+      - '@smithy/hash-node'
+      - '@smithy/signature-v4'
+      - ws
+
+  '@langchain/openrouter@0.4.3(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))(zod@4.4.3)':
+    dependencies:
+      '@langchain/core': 1.2.1(openai@6.45.0(zod@4.4.3))
+      '@langchain/openai': 1.5.3(@langchain/core@1.2.1(openai@6.45.0(zod@4.4.3)))
+      eventsource-parser: 3.1.0
+      openai: 6.45.0(zod@4.4.3)
+    transitivePeerDependencies:
+      - '@aws-sdk/credential-provider-node'
+      - '@smithy/hash-node'
+      - '@smithy/signature-v4'
+      - ws
+      - zod
 
   '@mdx-js/mdx@3.1.1':
     dependencies:
@@ -6854,6 +6918,8 @@ snapshots:
 
   eventemitter3@5.0.4: {}
 
+  eventsource-parser@3.1.0: {}
+
   expand-template@2.0.3: {}
 
   expect-type@1.4.0: {}
@@ -7474,9 +7540,11 @@ snapshots:
 
   klona@2.0.6: {}
 
-  langsmith@0.7.15:
+  langsmith@0.7.15(openai@6.45.0(zod@4.4.3)):
     dependencies:
       p-queue: 6.6.2
+    optionalDependencies:
+      openai: 6.45.0(zod@4.4.3)
 
   language-subtag-registry@0.3.23: {}
 
@@ -8185,6 +8253,10 @@ snapshots:
       regex: 6.1.0
       regex-recursion: 6.0.2
 
+  openai@6.45.0(zod@4.4.3):
+    optionalDependencies:
+      zod: 4.4.3
+
   optionator@0.9.4:
     dependencies:
       deep-is: 0.1.4