Add tests

__fixtures__/core.ts

@@ -5,6 +5,7 @@ export const debug = jest.fn<typeof core.debug>()
 export const error = jest.fn<typeof core.error>()
 export const info = jest.fn<typeof core.info>()
 export const getInput = jest.fn<typeof core.getInput>()
+export const getBooleanInput = jest.fn<typeof core.getBooleanInput>()
 export const setOutput = jest.fn<typeof core.setOutput>()
 export const setFailed = jest.fn<typeof core.setFailed>()
 export const warning = jest.fn<typeof core.warning>()

__tests__/helpers.test.ts

@@ -0,0 +1,147 @@
+/**
+ * Unit tests for the helpers module, src/helpers.ts
+ */
+import { jest } from '@jest/globals'
+import * as core from '../__fixtures__/core.js'
+
+// Mock fs module
+const mockExistsSync = jest.fn()
+const mockReadFileSync = jest.fn()
+
+jest.unstable_mockModule('fs', () => ({
+  existsSync: mockExistsSync,
+  readFileSync: mockReadFileSync
+}))
+
+jest.unstable_mockModule('@actions/core', () => core)
+
+// Import the module being tested
+const { loadContentFromFileOrInput } = await import('../src/helpers.js')
+
+describe('helpers.ts', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('loadContentFromFileOrInput', () => {
+    it('loads content from file when file path is provided', () => {
+      const filePath = '/path/to/file.txt'
+      const fileContent = 'File content here'
+
+      core.getInput.mockImplementation((name: string) => {
+        if (name === 'file-input') return filePath
+        if (name === 'content-input') return ''
+        return ''
+      })
+
+      mockExistsSync.mockReturnValue(true)
+      mockReadFileSync.mockReturnValue(fileContent)
+
+      const result = loadContentFromFileOrInput('file-input', 'content-input')
+
+      expect(core.getInput).toHaveBeenCalledWith('file-input')
+      expect(mockExistsSync).toHaveBeenCalledWith(filePath)
+      expect(mockReadFileSync).toHaveBeenCalledWith(filePath, 'utf-8')
+      expect(result).toBe(fileContent)
+    })
+
+    it('throws error when file path is provided but file does not exist', () => {
+      const filePath = '/path/to/nonexistent.txt'
+
+      core.getInput.mockImplementation((name: string) => {
+        if (name === 'file-input') return filePath
+        if (name === 'content-input') return ''
+        return ''
+      })
+
+      mockExistsSync.mockReturnValue(false)
+
+      expect(() => {
+        loadContentFromFileOrInput('file-input', 'content-input')
+      }).toThrow('File for file-input was not found: /path/to/nonexistent.txt')
+
+      expect(mockExistsSync).toHaveBeenCalledWith(filePath)
+      expect(mockReadFileSync).not.toHaveBeenCalled()
+    })
+
+    it('uses content input when file path is empty', () => {
+      const contentInput = 'Direct content input'
+
+      core.getInput.mockImplementation((name: string) => {
+        if (name === 'file-input') return ''
+        if (name === 'content-input') return contentInput
+        return ''
+      })
+
+      const result = loadContentFromFileOrInput('file-input', 'content-input')
+
+      expect(core.getInput).toHaveBeenCalledWith('file-input')
+      expect(core.getInput).toHaveBeenCalledWith('content-input')
+      expect(mockExistsSync).not.toHaveBeenCalled()
+      expect(mockReadFileSync).not.toHaveBeenCalled()
+      expect(result).toBe(contentInput)
+    })
+
+    it('prefers file path over content input when both are provided', () => {
+      const filePath = '/path/to/file.txt'
+      const fileContent = 'File content'
+      const contentInput = 'Direct content input'
+
+      core.getInput.mockImplementation((name: string) => {
+        if (name === 'file-input') return filePath
+        if (name === 'content-input') return contentInput
+        return ''
+      })
+
+      mockExistsSync.mockReturnValue(true)
+      mockReadFileSync.mockReturnValue(fileContent)
+
+      const result = loadContentFromFileOrInput('file-input', 'content-input')
+
+      expect(result).toBe(fileContent)
+      expect(mockExistsSync).toHaveBeenCalledWith(filePath)
+      expect(mockReadFileSync).toHaveBeenCalledWith(filePath, 'utf-8')
+    })
+
+    it('uses default value when neither file nor content is provided', () => {
+      const defaultValue = 'Default content'
+
+      core.getInput.mockImplementation(() => '')
+
+      const result = loadContentFromFileOrInput(
+        'file-input',
+        'content-input',
+        defaultValue
+      )
+
+      expect(result).toBe(defaultValue)
+      expect(mockExistsSync).not.toHaveBeenCalled()
+      expect(mockReadFileSync).not.toHaveBeenCalled()
+    })
+
+    it('throws error when neither file nor content is provided and no default', () => {
+      core.getInput.mockImplementation(() => '')
+
+      expect(() => {
+        loadContentFromFileOrInput('file-input', 'content-input')
+      }).toThrow('Neither file-input nor content-input was set')
+
+      expect(mockExistsSync).not.toHaveBeenCalled()
+      expect(mockReadFileSync).not.toHaveBeenCalled()
+    })
+
+    it('handles undefined inputs correctly', () => {
+      const defaultValue = 'Default content'
+
+      core.getInput.mockImplementation(() => undefined as any)
+
+      const result = loadContentFromFileOrInput(
+        'file-input',
+        'content-input',
+        defaultValue
+      )
+
+      expect(result).toBe(defaultValue)
+    })
+  })
+})

__tests__/inference.test.ts

@@ -0,0 +1,356 @@
+/**
+ * Unit tests for the inference module, src/inference.ts
+ */
+import { jest } from '@jest/globals'
+import * as core from '../__fixtures__/core.js'
+
+// Mock Azure AI Inference
+const mockPost = jest.fn() as jest.MockedFunction<any>
+const mockPath = jest.fn(() => ({ post: mockPost }))
+const mockClient = jest.fn(() => ({ path: mockPath }))
+
+jest.unstable_mockModule('@azure-rest/ai-inference', () => ({
+  default: mockClient,
+  isUnexpected: jest.fn(() => false)
+}))
+
+jest.unstable_mockModule('@azure/core-auth', () => ({
+  AzureKeyCredential: jest.fn()
+}))
+
+// Mock MCP functions
+const mockExecuteToolCalls = jest.fn() as jest.MockedFunction<any>
+jest.unstable_mockModule('../src/mcp.js', () => ({
+  executeToolCalls: mockExecuteToolCalls
+}))
+
+jest.unstable_mockModule('@actions/core', () => core)
+
+// Import the module being tested
+const { simpleInference, mcpInference } = await import('../src/inference.js')
+
+describe('inference.ts', () => {
+  const mockRequest = {
+    systemPrompt: 'You are a test assistant',
+    prompt: 'Hello, AI!',
+    modelName: 'gpt-4',
+    maxTokens: 100,
+    endpoint: 'https://api.test.com',
+    token: 'test-token'
+  }
+
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('simpleInference', () => {
+    it('performs simple inference without tools', async () => {
+      const mockResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Hello, user!'
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost.mockResolvedValue(mockResponse)
+
+      const result = await simpleInference(mockRequest)
+
+      expect(result).toBe('Hello, user!')
+      expect(core.info).toHaveBeenCalledWith(
+        'Running simple inference without tools'
+      )
+      expect(core.info).toHaveBeenCalledWith('Model response: Hello, user!')
+
+      // Verify the request structure
+      expect(mockPost).toHaveBeenCalledWith({
+        body: {
+          messages: [
+            {
+              role: 'system',
+              content: 'You are a test assistant'
+            },
+            {
+              role: 'user',
+              content: 'Hello, AI!'
+            }
+          ],
+          max_tokens: 100,
+          model: 'gpt-4'
+        }
+      })
+    })
+
+    it('handles null response content', async () => {
+      const mockResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: null
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost.mockResolvedValue(mockResponse)
+
+      const result = await simpleInference(mockRequest)
+
+      expect(result).toBeNull()
+      expect(core.info).toHaveBeenCalledWith(
+        'Model response: No response content'
+      )
+    })
+  })
+
+  describe('mcpInference', () => {
+    const mockMcpClient = {
+      client: {} as any,
+      tools: [
+        {
+          type: 'function',
+          function: {
+            name: 'test-tool',
+            description: 'A test tool',
+            parameters: { type: 'object' }
+          }
+        }
+      ]
+    }
+
+    it('performs inference without tool calls', async () => {
+      const mockResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Hello, user!',
+                tool_calls: null
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost.mockResolvedValue(mockResponse)
+
+      const result = await mcpInference(mockRequest, mockMcpClient)
+
+      expect(result).toBe('Hello, user!')
+      expect(core.info).toHaveBeenCalledWith('Running MCP inference with tools')
+      expect(core.info).toHaveBeenCalledWith('MCP inference iteration 1')
+      expect(core.info).toHaveBeenCalledWith(
+        'No tool calls requested, ending MCP inference loop'
+      )
+
+      // The MCP inference loop will always add the assistant message, even when there are no tool calls
+      // So we don't check the exact messages, just that tools were included
+      expect(mockPost).toHaveBeenCalledTimes(1)
+      const callArgs = mockPost.mock.calls[0][0] as any
+      expect(callArgs.body.tools).toEqual(mockMcpClient.tools)
+      expect(callArgs.body.model).toBe('gpt-4')
+      expect(callArgs.body.max_tokens).toBe(100)
+    })
+
+    it('executes tool calls and continues conversation', async () => {
+      const toolCalls = [
+        {
+          id: 'call-123',
+          function: {
+            name: 'test-tool',
+            arguments: '{"param": "value"}'
+          }
+        }
+      ]
+
+      const toolResults = [
+        {
+          tool_call_id: 'call-123',
+          role: 'tool',
+          name: 'test-tool',
+          content: 'Tool result'
+        }
+      ]
+
+      // First response with tool calls
+      const firstResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'I need to use a tool.',
+                tool_calls: toolCalls
+              }
+            }
+          ]
+        }
+      }
+
+      // Second response after tool execution
+      const secondResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Here is the final answer.',
+                tool_calls: null
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost
+        .mockResolvedValueOnce(firstResponse)
+        .mockResolvedValueOnce(secondResponse)
+
+      mockExecuteToolCalls.mockResolvedValue(toolResults)
+
+      const result = await mcpInference(mockRequest, mockMcpClient)
+
+      expect(result).toBe('Here is the final answer.')
+      expect(mockExecuteToolCalls).toHaveBeenCalledWith(
+        mockMcpClient.client,
+        toolCalls
+      )
+      expect(mockPost).toHaveBeenCalledTimes(2)
+
+      // Verify the second call includes the conversation history
+      const secondCall = mockPost.mock.calls[1][0] as any
+      expect(secondCall.body.messages).toHaveLength(5) // system, user, assistant, tool, assistant
+      expect(secondCall.body.messages[2].role).toBe('assistant')
+      expect(secondCall.body.messages[2].tool_calls).toEqual(toolCalls)
+      expect(secondCall.body.messages[3]).toEqual(toolResults[0])
+    })
+
+    it('handles maximum iteration limit', async () => {
+      const toolCalls = [
+        {
+          id: 'call-123',
+          function: {
+            name: 'test-tool',
+            arguments: '{}'
+          }
+        }
+      ]
+
+      const toolResults = [
+        {
+          tool_call_id: 'call-123',
+          role: 'tool',
+          name: 'test-tool',
+          content: 'Tool result'
+        }
+      ]
+
+      // Always respond with tool calls to trigger infinite loop
+      const responseWithToolCalls = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Using tool again.',
+                tool_calls: toolCalls
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost.mockResolvedValue(responseWithToolCalls)
+      mockExecuteToolCalls.mockResolvedValue(toolResults)
+
+      const result = await mcpInference(mockRequest, mockMcpClient)
+
+      expect(mockPost).toHaveBeenCalledTimes(5) // Max iterations reached
+      expect(core.warning).toHaveBeenCalledWith(
+        'MCP inference loop exceeded maximum iterations (5)'
+      )
+      expect(result).toBe('Using tool again.') // Last assistant message
+    })
+
+    it('handles empty tool calls array', async () => {
+      const mockResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Hello, user!',
+                tool_calls: []
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost.mockResolvedValue(mockResponse)
+
+      const result = await mcpInference(mockRequest, mockMcpClient)
+
+      expect(result).toBe('Hello, user!')
+      expect(core.info).toHaveBeenCalledWith(
+        'No tool calls requested, ending MCP inference loop'
+      )
+      expect(mockExecuteToolCalls).not.toHaveBeenCalled()
+    })
+
+    it('returns last assistant message when no content in final iteration', async () => {
+      const toolCalls = [
+        {
+          id: 'call-123',
+          function: { name: 'test-tool', arguments: '{}' }
+        }
+      ]
+
+      const firstResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'First message',
+                tool_calls: toolCalls
+              }
+            }
+          ]
+        }
+      }
+
+      const secondResponse = {
+        body: {
+          choices: [
+            {
+              message: {
+                content: 'Second message',
+                tool_calls: toolCalls
+              }
+            }
+          ]
+        }
+      }
+
+      mockPost
+        .mockResolvedValueOnce(firstResponse)
+        .mockResolvedValue(secondResponse)
+
+      mockExecuteToolCalls.mockResolvedValue([
+        {
+          tool_call_id: 'call-123',
+          role: 'tool',
+          name: 'test-tool',
+          content: 'result'
+        }
+      ])
+
+      const result = await mcpInference(mockRequest, mockMcpClient)
+
+      expect(result).toBe('Second message')
+    })
+  })
+})

__tests__/main.test.new.ts

@@ -0,0 +1,264 @@
+/**
+ * Unit tests for the action's main functionality, src/main.ts
+ */
+import { jest } from '@jest/globals'
+import * as core from '../__fixtures__/core.js'
+
+// Default to throwing errors to catch unexpected calls
+const mockExistsSync = jest.fn().mockImplementation(() => {
+  throw new Error(
+    'Unexpected call to existsSync - test should override this implementation'
+  )
+})
+const mockReadFileSync = jest.fn().mockImplementation(() => {
+  throw new Error(
+    'Unexpected call to readFileSync - test should override this implementation'
+  )
+})
+const mockWriteFileSync = jest.fn()
+
+/**
+ * Helper function to mock file system operations for one or more files
+ * @param fileContents - Object mapping file paths to their contents
+ * @param nonExistentFiles - Array of file paths that should be treated as non-existent
+ */
+function mockFileContent(
+  fileContents: Record<string, string> = {},
+  nonExistentFiles: string[] = []
+): void {
+  // Mock existsSync to return true for files that exist, false for those that don't
+  mockExistsSync.mockImplementation((...args: unknown[]): boolean => {
+    const [path] = args as [string]
+    if (nonExistentFiles.includes(path)) {
+      return false
+    }
+    return path in fileContents || true
+  })
+
+  // Mock readFileSync to return the content for known files
+  mockReadFileSync.mockImplementation((...args: unknown[]): string => {
+    const [path, options] = args as [string, BufferEncoding]
+    if (options === 'utf-8' && path in fileContents) {
+      return fileContents[path]
+    }
+    throw new Error(`Unexpected file read: ${path}`)
+  })
+}
+
+/**
+ * Helper function to mock action inputs
+ * @param inputs - Object mapping input names to their values
+ */
+function mockInputs(inputs: Record<string, string> = {}): void {
+  // Default values that are applied unless overridden
+  const defaultInputs: Record<string, string> = {
+    token: 'fake-token',
+    model: 'gpt-4',
+    'max-tokens': '100',
+    endpoint: 'https://api.test.com'
+  }
+
+  // Combine defaults with user-provided inputs
+  const allInputs: Record<string, string> = { ...defaultInputs, ...inputs }
+
+  core.getInput.mockImplementation((name: string) => {
+    return allInputs[name] || ''
+  })
+
+  core.getBooleanInput.mockImplementation((name: string) => {
+    const value = allInputs[name]
+    return value === 'true'
+  })
+}
+
+/**
+ * Helper function to verify common response assertions
+ */
+function verifyStandardResponse(): void {
+  expect(core.setOutput).toHaveBeenNthCalledWith(1, 'response', 'Hello, user!')
+  expect(core.setOutput).toHaveBeenNthCalledWith(
+    2,
+    'response-file',
+    expect.stringContaining('modelResponse.txt')
+  )
+}
+
+jest.unstable_mockModule('fs', () => ({
+  existsSync: mockExistsSync,
+  readFileSync: mockReadFileSync,
+  writeFileSync: mockWriteFileSync
+}))
+
+// Mock MCP and inference modules
+const mockConnectToMCP = jest.fn() as jest.MockedFunction<any>
+const mockSimpleInference = jest.fn() as jest.MockedFunction<any>
+const mockMcpInference = jest.fn() as jest.MockedFunction<any>
+
+jest.unstable_mockModule('../src/mcp.js', () => ({
+  connectToMCP: mockConnectToMCP
+}))
+
+jest.unstable_mockModule('../src/inference.js', () => ({
+  simpleInference: mockSimpleInference,
+  mcpInference: mockMcpInference
+}))
+
+jest.unstable_mockModule('@actions/core', () => core)
+
+// The module being tested should be imported dynamically. This ensures that the
+// mocks are used in place of any actual dependencies.
+const { run } = await import('../src/main.js')
+
+describe('main.ts', () => {
+  // Reset all mocks before each test
+  beforeEach(() => {
+    jest.clearAllMocks()
+
+    // Set up default mock responses
+    mockSimpleInference.mockResolvedValue('Hello, user!')
+    mockMcpInference.mockResolvedValue('Hello, user!')
+  })
+
+  it('Sets the response output', async () => {
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.'
+    })
+
+    await run()
+
+    expect(core.setOutput).toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('Sets a failed status when no prompt is set', async () => {
+    mockInputs({
+      prompt: '',
+      'prompt-file': ''
+    })
+
+    await run()
+
+    expect(core.setFailed).toHaveBeenNthCalledWith(
+      1,
+      'Neither prompt-file nor prompt was set'
+    )
+  })
+
+  it('uses simple inference when MCP is disabled', async () => {
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'false'
+    })
+
+    await run()
+
+    expect(mockSimpleInference).toHaveBeenCalledWith({
+      systemPrompt: 'You are a test assistant.',
+      prompt: 'Hello, AI!',
+      modelName: 'gpt-4',
+      maxTokens: 100,
+      endpoint: 'https://api.test.com',
+      token: 'fake-token'
+    })
+    expect(mockConnectToMCP).not.toHaveBeenCalled()
+    expect(mockMcpInference).not.toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('uses MCP inference when enabled and connection succeeds', async () => {
+    const mockMcpClient = {
+      client: {} as any,
+      tools: [{ type: 'function', function: { name: 'test-tool' } }]
+    }
+
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'true'
+    })
+
+    mockConnectToMCP.mockResolvedValue(mockMcpClient)
+
+    await run()
+
+    expect(mockConnectToMCP).toHaveBeenCalledWith('fake-token')
+    expect(mockMcpInference).toHaveBeenCalledWith(
+      expect.objectContaining({
+        systemPrompt: 'You are a test assistant.',
+        prompt: 'Hello, AI!',
+        token: 'fake-token'
+      }),
+      mockMcpClient
+    )
+    expect(mockSimpleInference).not.toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('falls back to simple inference when MCP connection fails', async () => {
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'true'
+    })
+
+    mockConnectToMCP.mockResolvedValue(null)
+
+    await run()
+
+    expect(mockConnectToMCP).toHaveBeenCalledWith('fake-token')
+    expect(mockSimpleInference).toHaveBeenCalled()
+    expect(mockMcpInference).not.toHaveBeenCalled()
+    expect(core.warning).toHaveBeenCalledWith(
+      'MCP connection failed, falling back to simple inference'
+    )
+    verifyStandardResponse()
+  })
+
+  it('properly integrates with loadContentFromFileOrInput', async () => {
+    const promptFile = 'prompt.txt'
+    const systemPromptFile = 'system-prompt.txt'
+    const promptContent = 'File-based prompt'
+    const systemPromptContent = 'File-based system prompt'
+
+    mockFileContent({
+      [promptFile]: promptContent,
+      [systemPromptFile]: systemPromptContent
+    })
+
+    mockInputs({
+      'prompt-file': promptFile,
+      'system-prompt-file': systemPromptFile,
+      'enable-mcp': 'false'
+    })
+
+    await run()
+
+    expect(mockSimpleInference).toHaveBeenCalledWith({
+      systemPrompt: systemPromptContent,
+      prompt: promptContent,
+      modelName: 'gpt-4',
+      maxTokens: 100,
+      endpoint: 'https://api.test.com',
+      token: 'fake-token'
+    })
+    verifyStandardResponse()
+  })
+
+  it('handles non-existent prompt-file with an error', async () => {
+    const promptFile = 'non-existent-prompt.txt'
+
+    mockFileContent({}, [promptFile])
+
+    mockInputs({
+      'prompt-file': promptFile
+    })
+
+    await run()
+
+    expect(core.setFailed).toHaveBeenCalledWith(
+      `File for prompt-file was not found: ${promptFile}`
+    )
+  })
+})

__tests__/main.test.old.ts

@@ -0,0 +1,383 @@
+/**
+ * Unit tests for the action's main functionality, src/main.ts
+ */
+import { jest } from '@jest/globals'
+import * as core from '../__fixtures__/core.js'
+
+// Default to throwing errors to catch unexpected calls
+const mockExistsSync = jest.fn().mockImplementation(() => {
+  throw new Error(
+    'Unexpected call to existsSync - test should override this implementation'
+  )
+})
+const mockReadFileSync = jest.fn().mockImplementation(() => {
+  throw new Error(
+    'Unexpected call to readFileSync - test should override this implementation'
+  )
+})
+const mockWriteFileSync = jest.fn()
+
+/**
+ * Helper function to mock file system operations for one or more files
+ * @param fileContents - Object mapping file paths to their contents
+ * @param nonExistentFiles - Array of file paths that should be treated as non-existent
+ */
+function mockFileContent(
+  fileContents: Record<string, string> = {},
+  nonExistentFiles: string[] = []
+): void {
+  // Mock existsSync to return true for files that exist, false for those that don't
+  mockExistsSync.mockImplementation((...args: unknown[]): boolean => {
+    const [path] = args as [string]
+    if (nonExistentFiles.includes(path)) {
+      return false
+    }
+    return path in fileContents || true
+  })
+
+  // Mock readFileSync to return the content for known files
+  mockReadFileSync.mockImplementation((...args: unknown[]): string => {
+    const [path, options] = args as [string, BufferEncoding]
+    if (options === 'utf-8' && path in fileContents) {
+      return fileContents[path]
+    }
+    throw new Error(`Unexpected file read: ${path}`)
+  })
+}
+
+/**
+ * Helper function to mock action inputs
+ * @param inputs - Object mapping input names to their values
+ */
+function mockInputs(inputs: Record<string, string> = {}): void {
+  // Default values that are applied unless overridden
+  const defaultInputs: Record<string, string> = {
+    token: 'fake-token',
+    model: 'gpt-4',
+    'max-tokens': '100',
+    endpoint: 'https://api.test.com'
+  }
+
+  // Combine defaults with user-provided inputs
+  const allInputs: Record<string, string> = { ...defaultInputs, ...inputs }
+
+  core.getInput.mockImplementation((name: string) => {
+    return allInputs[name] || ''
+  })
+  
+  core.getBooleanInput.mockImplementation((name: string) => {
+    const value = allInputs[name]
+    return value === 'true'
+  })
+}
+
+/**
+ * Helper function to verify common response assertions
+ */
+function verifyStandardResponse(): void {
+  expect(core.setOutput).toHaveBeenNthCalledWith(1, 'response', 'Hello, user!')
+  expect(core.setOutput).toHaveBeenNthCalledWith(
+    2,
+    'response-file',
+    expect.stringContaining('modelResponse.txt')
+  )
+}
+
+jest.unstable_mockModule('fs', () => ({
+  existsSync: mockExistsSync,
+  readFileSync: mockReadFileSync,
+  writeFileSync: mockWriteFileSync
+}))
+
+// Mock MCP and inference modules
+const mockConnectToMCP = jest.fn() as jest.MockedFunction<any>
+const mockSimpleInference = jest.fn() as jest.MockedFunction<any>
+const mockMcpInference = jest.fn() as jest.MockedFunction<any>
+
+jest.unstable_mockModule('../src/mcp.js', () => ({
+  connectToMCP: mockConnectToMCP
+}))
+
+jest.unstable_mockModule('../src/inference.js', () => ({
+  simpleInference: mockSimpleInference,
+  mcpInference: mockMcpInference
+}))
+
+jest.unstable_mockModule('@actions/core', () => core)
+
+// The module being tested should be imported dynamically. This ensures that the
+// mocks are used in place of any actual dependencies.
+const { run } = await import('../src/main.js')
+
+describe('main.ts', () => {
+  // Reset all mocks before each test
+  beforeEach(() => {
+    jest.clearAllMocks()
+    
+    // Set up default mock responses
+    mockSimpleInference.mockResolvedValue('Hello, user!')
+    mockMcpInference.mockResolvedValue('Hello, user!')
+  })
+
+  it('Sets the response output', async () => {
+    // Set the action's inputs as return values from core.getInput().
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.'
+    })
+
+    await run()
+
+    expect(core.setOutput).toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('Sets a failed status when no prompt is set', async () => {
+    // Clear the getInput mock and simulate no prompt or prompt-file input
+    mockInputs({
+      prompt: '',
+      'prompt-file': ''
+    })
+
+    await run()
+
+    // Verify that the action was marked as failed.
+    expect(core.setFailed).toHaveBeenNthCalledWith(
+      1,
+      'Neither prompt-file nor prompt was set'
+    )
+  })
+
+  it('uses prompt-file', async () => {
+    const promptFile = 'prompt.txt'
+    const promptContent = 'This is a prompt from a file'
+
+    // Set up mock to return specific content for the prompt file
+    mockFileContent({
+      [promptFile]: promptContent
+    })
+
+    // Set up input mocks
+    mockInputs({
+      'prompt-file': promptFile,
+      'system-prompt': 'You are a test assistant.'
+    })
+
+    await run()
+
+    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
+    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
+    verifyStandardResponse()
+  })
+
+  it('handles non-existent prompt-file with an error', async () => {
+    const promptFile = 'non-existent-prompt.txt'
+
+    // Mock the file not existing
+    mockFileContent({}, [promptFile])
+
+    // Set up input mocks
+    mockInputs({
+      'prompt-file': promptFile
+    })
+
+    await run()
+
+    // Verify that the error was correctly reported
+    expect(core.setFailed).toHaveBeenCalledWith(
+      `File for prompt-file was not found: ${promptFile}`
+    )
+  })
+
+  it('prefers prompt-file over prompt when both are provided', async () => {
+    const promptFile = 'prompt.txt'
+    const promptFileContent = 'This is a prompt from a file that should be used'
+    const promptString = 'This is a direct prompt that should be ignored'
+
+    // Set up mock to return specific content for the prompt file
+    mockFileContent({
+      [promptFile]: promptFileContent
+    })
+
+    // Set up input mocks
+    mockInputs({
+      prompt: promptString,
+      'prompt-file': promptFile,
+      'system-prompt': 'You are a test assistant.'
+    })
+
+    await run()
+
+    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
+    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
+
+    // Check that the post call was made with the prompt from the file, not the input parameter
+    expect(mockPost).toHaveBeenCalledWith({
+      body: {
+        messages: [
+          {
+            role: 'system',
+            content: expect.any(String)
+          },
+          { role: 'user', content: promptFileContent } // Should use the file content, not the string input
+        ],
+        max_tokens: expect.any(Number),
+        model: expect.any(String)
+      }
+    })
+
+    verifyStandardResponse()
+  })
+
+  it('uses system-prompt-file', async () => {
+    const systemPromptFile = 'system-prompt.txt'
+    const systemPromptContent =
+      'You are a specialized system assistant for testing'
+
+    // Set up mock to return specific content for the system prompt file
+    mockFileContent({
+      [systemPromptFile]: systemPromptContent
+    })
+
+    // Set up input mocks
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt-file': systemPromptFile
+    })
+
+    await run()
+
+    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
+    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
+    verifyStandardResponse()
+  })
+
+  it('handles non-existent system-prompt-file with an error', async () => {
+    const systemPromptFile = 'non-existent-system-prompt.txt'
+
+    // Mock the file not existing
+    mockFileContent({}, [systemPromptFile])
+
+    // Set up input mocks
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt-file': systemPromptFile
+    })
+
+    await run()
+
+    // Verify that the error was correctly reported
+    expect(core.setFailed).toHaveBeenCalledWith(
+      `File for system-prompt-file was not found: ${systemPromptFile}`
+    )
+  })
+
+  it('prefers system-prompt-file over system-prompt when both are provided', async () => {
+    const systemPromptFile = 'system-prompt.txt'
+    const systemPromptFileContent =
+      'You are a specialized system assistant from file'
+    const systemPromptString =
+      'You are a basic system assistant from input parameter'
+
+    // Set up mock to return specific content for the system prompt file
+    mockFileContent({
+      [systemPromptFile]: systemPromptFileContent
+    })
+
+    // Set up input mocks
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt-file': systemPromptFile,
+      'system-prompt': systemPromptString
+    })
+
+    await run()
+
+    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
+    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
+
+    // Check that the post call was made with the system prompt from the file, not the input parameter
+    expect(mockPost).toHaveBeenCalledWith({
+      body: {
+        messages: [
+          {
+            role: 'system',
+            content: systemPromptFileContent // Should use the file content, not the string input
+          },
+          { role: 'user', content: 'Hello, AI!' }
+        ],
+        max_tokens: expect.any(Number),
+        model: expect.any(String)
+      }
+    })
+
+    verifyStandardResponse()
+  })
+
+  it('uses both prompt-file and system-prompt-file together', async () => {
+    const promptFile = 'prompt.txt'
+    const promptContent = 'This is a prompt from a file'
+    const systemPromptFile = 'system-prompt.txt'
+    const systemPromptContent =
+      'You are a specialized system assistant from file'
+
+    // Set up mock to return specific content for both files
+    mockFileContent({
+      [promptFile]: promptContent,
+      [systemPromptFile]: systemPromptContent
+    })
+
+    // Set up input mocks
+    mockInputs({
+      'prompt-file': promptFile,
+      'system-prompt-file': systemPromptFile
+    })
+
+    await run()
+
+    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
+    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
+    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
+    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
+
+    // Check that the post call was made with both the prompt and system prompt from files
+    expect(mockPost).toHaveBeenCalledWith({
+      body: {
+        messages: [
+          {
+            role: 'system',
+            content: systemPromptContent
+          },
+          { role: 'user', content: promptContent }
+        ],
+        max_tokens: expect.any(Number),
+        model: expect.any(String)
+      }
+    })
+
+    verifyStandardResponse()
+  })
+
+  it('passes custom max-tokens parameter to the model', async () => {
+    const customMaxTokens = 500
+
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'max-tokens': customMaxTokens.toString()
+    })
+
+    await run()
+
+    // Check that the post call was made with the correct max_tokens parameter
+    expect(mockPost).toHaveBeenCalledWith({
+      body: {
+        messages: expect.any(Array),
+        max_tokens: customMaxTokens,
+        model: expect.any(String)
+      }
+    })
+
+    verifyStandardResponse()
+  })
+})

__tests__/main.test.ts

@@ -1,32 +1,8 @@
 /**
  * Unit tests for the action's main functionality, src/main.ts
- *
- * To mock dependencies in ESM, you can create fixtures that export mock
- * functions and objects. For example, the core module is mocked in this test,
- * so that the actual '@actions/core' module is not imported.
  */
 import { jest } from '@jest/globals'
 import * as core from '../__fixtures__/core.js'
-const mockPost = jest.fn().mockImplementation(() => ({
-  body: {
-    choices: [
-      {
-        message: {
-          content: 'Hello, user!'
-        }
-      }
-    ]
-  }
-}))
-
-jest.unstable_mockModule('@azure-rest/ai-inference', () => ({
-  default: jest.fn(() => ({
-    path: jest.fn(() => ({
-      post: mockPost
-    }))
-  })),
-  isUnexpected: jest.fn(() => false)
-}))
 
 // Default to throwing errors to catch unexpected calls
 const mockExistsSync = jest.fn().mockImplementation(() => {
@@ -39,6 +15,7 @@ const mockReadFileSync = jest.fn().mockImplementation(() => {
     'Unexpected call to readFileSync - test should override this implementation'
   )
 })
+const mockWriteFileSync = jest.fn()
 
 /**
  * Helper function to mock file system operations for one or more files
@@ -75,7 +52,10 @@ function mockFileContent(
 function mockInputs(inputs: Record<string, string> = {}): void {
   // Default values that are applied unless overridden
   const defaultInputs: Record<string, string> = {
-    token: 'fake-token'
+    token: 'fake-token',
+    model: 'gpt-4',
+    'max-tokens': '100',
+    endpoint: 'https://api.test.com'
   }
 
   // Combine defaults with user-provided inputs
@@ -84,6 +64,11 @@ function mockInputs(inputs: Record<string, string> = {}): void {
   core.getInput.mockImplementation((name: string) => {
     return allInputs[name] || ''
   })
+
+  core.getBooleanInput.mockImplementation((name: string) => {
+    const value = allInputs[name]
+    return value === 'true'
+  })
 }
 
 /**
@@ -100,7 +85,22 @@ function verifyStandardResponse(): void {
 
 jest.unstable_mockModule('fs', () => ({
   existsSync: mockExistsSync,
-  readFileSync: mockReadFileSync
+  readFileSync: mockReadFileSync,
+  writeFileSync: mockWriteFileSync
+}))
+
+// Mock MCP and inference modules
+const mockConnectToMCP = jest.fn() as jest.MockedFunction<any>
+const mockSimpleInference = jest.fn() as jest.MockedFunction<any>
+const mockMcpInference = jest.fn() as jest.MockedFunction<any>
+
+jest.unstable_mockModule('../src/mcp.js', () => ({
+  connectToMCP: mockConnectToMCP
+}))
+
+jest.unstable_mockModule('../src/inference.js', () => ({
+  simpleInference: mockSimpleInference,
+  mcpInference: mockMcpInference
 }))
 
 jest.unstable_mockModule('@actions/core', () => core)
@@ -113,10 +113,16 @@ describe('main.ts', () => {
   // Reset all mocks before each test
   beforeEach(() => {
     jest.clearAllMocks()
+
+    // Remove any existing GITHUB_TOKEN
+    delete process.env.GITHUB_TOKEN
+
+    // Set up default mock responses
+    mockSimpleInference.mockResolvedValue('Hello, user!')
+    mockMcpInference.mockResolvedValue('Hello, user!')
   })
 
   it('Sets the response output', async () => {
-    // Set the action's inputs as return values from core.getInput().
     mockInputs({
       prompt: 'Hello, AI!',
       'system-prompt': 'You are a test assistant.'
@@ -129,7 +135,6 @@ describe('main.ts', () => {
   })
 
   it('Sets a failed status when no prompt is set', async () => {
-    // Clear the getInput mock and simulate no prompt or prompt-file input
     mockInputs({
       prompt: '',
       'prompt-file': ''
@@ -137,243 +142,126 @@ describe('main.ts', () => {
 
     await run()
 
-    // Verify that the action was marked as failed.
     expect(core.setFailed).toHaveBeenNthCalledWith(
       1,
       'Neither prompt-file nor prompt was set'
     )
   })
 
-  it('uses prompt-file', async () => {
-    const promptFile = 'prompt.txt'
-    const promptContent = 'This is a prompt from a file'
-
-    // Set up mock to return specific content for the prompt file
-    mockFileContent({
-      [promptFile]: promptContent
-    })
-
-    // Set up input mocks
+  it('uses simple inference when MCP is disabled', async () => {
     mockInputs({
-      'prompt-file': promptFile,
-      'system-prompt': 'You are a test assistant.'
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'false'
     })
 
     await run()
 
-    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
-    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
+    expect(mockSimpleInference).toHaveBeenCalledWith({
+      systemPrompt: 'You are a test assistant.',
+      prompt: 'Hello, AI!',
+      modelName: 'gpt-4',
+      maxTokens: 100,
+      endpoint: 'https://api.test.com',
+      token: 'fake-token'
+    })
+    expect(mockConnectToMCP).not.toHaveBeenCalled()
+    expect(mockMcpInference).not.toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('uses MCP inference when enabled and connection succeeds', async () => {
+    const mockMcpClient = {
+      client: {} as any,
+      tools: [{ type: 'function', function: { name: 'test-tool' } }]
+    }
+
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'true'
+    })
+
+    mockConnectToMCP.mockResolvedValue(mockMcpClient)
+
+    await run()
+
+    expect(mockConnectToMCP).toHaveBeenCalledWith('fake-token')
+    expect(mockMcpInference).toHaveBeenCalledWith(
+      expect.objectContaining({
+        systemPrompt: 'You are a test assistant.',
+        prompt: 'Hello, AI!',
+        token: 'fake-token'
+      }),
+      mockMcpClient
+    )
+    expect(mockSimpleInference).not.toHaveBeenCalled()
+    verifyStandardResponse()
+  })
+
+  it('falls back to simple inference when MCP connection fails', async () => {
+    mockInputs({
+      prompt: 'Hello, AI!',
+      'system-prompt': 'You are a test assistant.',
+      'enable-mcp': 'true'
+    })
+
+    mockConnectToMCP.mockResolvedValue(null)
+
+    await run()
+
+    expect(mockConnectToMCP).toHaveBeenCalledWith('fake-token')
+    expect(mockSimpleInference).toHaveBeenCalled()
+    expect(mockMcpInference).not.toHaveBeenCalled()
+    expect(core.warning).toHaveBeenCalledWith(
+      'MCP connection failed, falling back to simple inference'
+    )
+    verifyStandardResponse()
+  })
+
+  it('properly integrates with loadContentFromFileOrInput', async () => {
+    const promptFile = 'prompt.txt'
+    const systemPromptFile = 'system-prompt.txt'
+    const promptContent = 'File-based prompt'
+    const systemPromptContent = 'File-based system prompt'
+
+    mockFileContent({
+      [promptFile]: promptContent,
+      [systemPromptFile]: systemPromptContent
+    })
+
+    mockInputs({
+      'prompt-file': promptFile,
+      'system-prompt-file': systemPromptFile,
+      'enable-mcp': 'false'
+    })
+
+    await run()
+
+    expect(mockSimpleInference).toHaveBeenCalledWith({
+      systemPrompt: systemPromptContent,
+      prompt: promptContent,
+      modelName: 'gpt-4',
+      maxTokens: 100,
+      endpoint: 'https://api.test.com',
+      token: 'fake-token'
+    })
     verifyStandardResponse()
   })
 
   it('handles non-existent prompt-file with an error', async () => {
     const promptFile = 'non-existent-prompt.txt'
 
-    // Mock the file not existing
     mockFileContent({}, [promptFile])
 
-    // Set up input mocks
     mockInputs({
       'prompt-file': promptFile
     })
 
     await run()
 
-    // Verify that the error was correctly reported
     expect(core.setFailed).toHaveBeenCalledWith(
       `File for prompt-file was not found: ${promptFile}`
     )
   })
-
-  it('prefers prompt-file over prompt when both are provided', async () => {
-    const promptFile = 'prompt.txt'
-    const promptFileContent = 'This is a prompt from a file that should be used'
-    const promptString = 'This is a direct prompt that should be ignored'
-
-    // Set up mock to return specific content for the prompt file
-    mockFileContent({
-      [promptFile]: promptFileContent
-    })
-
-    // Set up input mocks
-    mockInputs({
-      prompt: promptString,
-      'prompt-file': promptFile,
-      'system-prompt': 'You are a test assistant.'
-    })
-
-    await run()
-
-    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
-    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
-
-    // Check that the post call was made with the prompt from the file, not the input parameter
-    expect(mockPost).toHaveBeenCalledWith({
-      body: {
-        messages: [
-          {
-            role: 'system',
-            content: expect.any(String)
-          },
-          { role: 'user', content: promptFileContent } // Should use the file content, not the string input
-        ],
-        max_tokens: expect.any(Number),
-        model: expect.any(String)
-      }
-    })
-
-    verifyStandardResponse()
-  })
-
-  it('uses system-prompt-file', async () => {
-    const systemPromptFile = 'system-prompt.txt'
-    const systemPromptContent =
-      'You are a specialized system assistant for testing'
-
-    // Set up mock to return specific content for the system prompt file
-    mockFileContent({
-      [systemPromptFile]: systemPromptContent
-    })
-
-    // Set up input mocks
-    mockInputs({
-      prompt: 'Hello, AI!',
-      'system-prompt-file': systemPromptFile
-    })
-
-    await run()
-
-    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
-    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
-    verifyStandardResponse()
-  })
-
-  it('handles non-existent system-prompt-file with an error', async () => {
-    const systemPromptFile = 'non-existent-system-prompt.txt'
-
-    // Mock the file not existing
-    mockFileContent({}, [systemPromptFile])
-
-    // Set up input mocks
-    mockInputs({
-      prompt: 'Hello, AI!',
-      'system-prompt-file': systemPromptFile
-    })
-
-    await run()
-
-    // Verify that the error was correctly reported
-    expect(core.setFailed).toHaveBeenCalledWith(
-      `File for system-prompt-file was not found: ${systemPromptFile}`
-    )
-  })
-
-  it('prefers system-prompt-file over system-prompt when both are provided', async () => {
-    const systemPromptFile = 'system-prompt.txt'
-    const systemPromptFileContent =
-      'You are a specialized system assistant from file'
-    const systemPromptString =
-      'You are a basic system assistant from input parameter'
-
-    // Set up mock to return specific content for the system prompt file
-    mockFileContent({
-      [systemPromptFile]: systemPromptFileContent
-    })
-
-    // Set up input mocks
-    mockInputs({
-      prompt: 'Hello, AI!',
-      'system-prompt-file': systemPromptFile,
-      'system-prompt': systemPromptString
-    })
-
-    await run()
-
-    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
-    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
-
-    // Check that the post call was made with the system prompt from the file, not the input parameter
-    expect(mockPost).toHaveBeenCalledWith({
-      body: {
-        messages: [
-          {
-            role: 'system',
-            content: systemPromptFileContent // Should use the file content, not the string input
-          },
-          { role: 'user', content: 'Hello, AI!' }
-        ],
-        max_tokens: expect.any(Number),
-        model: expect.any(String)
-      }
-    })
-
-    verifyStandardResponse()
-  })
-
-  it('uses both prompt-file and system-prompt-file together', async () => {
-    const promptFile = 'prompt.txt'
-    const promptContent = 'This is a prompt from a file'
-    const systemPromptFile = 'system-prompt.txt'
-    const systemPromptContent =
-      'You are a specialized system assistant from file'
-
-    // Set up mock to return specific content for both files
-    mockFileContent({
-      [promptFile]: promptContent,
-      [systemPromptFile]: systemPromptContent
-    })
-
-    // Set up input mocks
-    mockInputs({
-      'prompt-file': promptFile,
-      'system-prompt-file': systemPromptFile
-    })
-
-    await run()
-
-    expect(mockExistsSync).toHaveBeenCalledWith(promptFile)
-    expect(mockExistsSync).toHaveBeenCalledWith(systemPromptFile)
-    expect(mockReadFileSync).toHaveBeenCalledWith(promptFile, 'utf-8')
-    expect(mockReadFileSync).toHaveBeenCalledWith(systemPromptFile, 'utf-8')
-
-    // Check that the post call was made with both the prompt and system prompt from files
-    expect(mockPost).toHaveBeenCalledWith({
-      body: {
-        messages: [
-          {
-            role: 'system',
-            content: systemPromptContent
-          },
-          { role: 'user', content: promptContent }
-        ],
-        max_tokens: expect.any(Number),
-        model: expect.any(String)
-      }
-    })
-
-    verifyStandardResponse()
-  })
-
-  it('passes custom max-tokens parameter to the model', async () => {
-    const customMaxTokens = 500
-
-    mockInputs({
-      prompt: 'Hello, AI!',
-      'system-prompt': 'You are a test assistant.',
-      'max-tokens': customMaxTokens.toString()
-    })
-
-    await run()
-
-    // Check that the post call was made with the correct max_tokens parameter
-    expect(mockPost).toHaveBeenCalledWith({
-      body: {
-        messages: expect.any(Array),
-        max_tokens: customMaxTokens,
-        model: expect.any(String)
-      }
-    })
-
-    verifyStandardResponse()
-  })
 })

__tests__/mcp.test.ts

@@ -0,0 +1,280 @@
+/**
+ * Unit tests for the MCP module, src/mcp.ts
+ */
+import { jest } from '@jest/globals'
+import * as core from '../__fixtures__/core.js'
+
+// Mock MCP SDK
+const mockConnect = jest.fn() as jest.MockedFunction<any>
+const mockListTools = jest.fn() as jest.MockedFunction<any>
+const mockCallTool = jest.fn() as jest.MockedFunction<any>
+
+const mockClient = {
+  connect: mockConnect,
+  listTools: mockListTools,
+  callTool: mockCallTool
+} as any
+
+jest.unstable_mockModule('@modelcontextprotocol/sdk/client/index.js', () => ({
+  Client: jest.fn(() => mockClient)
+}))
+
+jest.unstable_mockModule(
+  '@modelcontextprotocol/sdk/client/streamableHttp.js',
+  () => ({
+    StreamableHTTPClientTransport: jest.fn()
+  })
+)
+
+jest.unstable_mockModule('@actions/core', () => core)
+
+// Import the module being tested
+const { connectToMCP, executeToolCall, executeToolCalls } = await import(
+  '../src/mcp.js'
+)
+
+describe('mcp.ts', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  describe('connectToMCP', () => {
+    it('successfully connects to MCP server and retrieves tools', async () => {
+      const token = 'test-token'
+      const mockTools = [
+        {
+          name: 'test-tool-1',
+          description: 'Test tool 1',
+          inputSchema: { type: 'object', properties: {} }
+        },
+        {
+          name: 'test-tool-2',
+          description: 'Test tool 2',
+          inputSchema: {
+            type: 'object',
+            properties: { param: { type: 'string' } }
+          }
+        }
+      ]
+
+      mockConnect.mockResolvedValue(undefined)
+      mockListTools.mockResolvedValue({ tools: mockTools })
+
+      const result = await connectToMCP(token)
+
+      expect(result).not.toBeNull()
+      expect(result?.client).toBe(mockClient)
+      expect(result?.tools).toHaveLength(2)
+      expect(result?.tools[0]).toEqual({
+        type: 'function',
+        function: {
+          name: 'test-tool-1',
+          description: 'Test tool 1',
+          parameters: { type: 'object', properties: {} }
+        }
+      })
+      expect(core.info).toHaveBeenCalledWith(
+        'Connecting to GitHub MCP server...'
+      )
+      expect(core.info).toHaveBeenCalledWith(
+        'Successfully connected to MCP server'
+      )
+      expect(core.info).toHaveBeenCalledWith(
+        'Retrieved 2 tools from MCP server'
+      )
+      expect(core.info).toHaveBeenCalledWith(
+        'Mapped 2 tools for Azure AI Inference'
+      )
+    })
+
+    it('returns null when connection fails', async () => {
+      const token = 'test-token'
+      const connectionError = new Error('Connection failed')
+
+      mockConnect.mockRejectedValue(connectionError)
+
+      const result = await connectToMCP(token)
+
+      expect(result).toBeNull()
+      expect(core.warning).toHaveBeenCalledWith(
+        'Failed to connect to MCP server: Error: Connection failed'
+      )
+    })
+
+    it('handles empty tools list', async () => {
+      const token = 'test-token'
+
+      mockConnect.mockResolvedValue(undefined)
+      mockListTools.mockResolvedValue({ tools: [] })
+
+      const result = await connectToMCP(token)
+
+      expect(result).not.toBeNull()
+      expect(result?.tools).toHaveLength(0)
+      expect(core.info).toHaveBeenCalledWith(
+        'Retrieved 0 tools from MCP server'
+      )
+      expect(core.info).toHaveBeenCalledWith(
+        'Mapped 0 tools for Azure AI Inference'
+      )
+    })
+
+    it('handles undefined tools list', async () => {
+      const token = 'test-token'
+
+      mockConnect.mockResolvedValue(undefined)
+      mockListTools.mockResolvedValue({})
+
+      const result = await connectToMCP(token)
+
+      expect(result).not.toBeNull()
+      expect(result?.tools).toHaveLength(0)
+      expect(core.info).toHaveBeenCalledWith(
+        'Retrieved 0 tools from MCP server'
+      )
+    })
+  })
+
+  describe('executeToolCall', () => {
+    it('successfully executes a tool call', async () => {
+      const toolCall = {
+        id: 'call-123',
+        function: {
+          name: 'test-tool',
+          arguments: '{"param": "value"}'
+        }
+      }
+      const toolResult = {
+        content: [{ type: 'text', text: 'Tool execution result' }]
+      }
+
+      mockCallTool.mockResolvedValue(toolResult)
+
+      const result = await executeToolCall(mockClient, toolCall)
+
+      expect(mockCallTool).toHaveBeenCalledWith({
+        name: 'test-tool',
+        arguments: { param: 'value' }
+      })
+      expect(result).toEqual({
+        tool_call_id: 'call-123',
+        role: 'tool',
+        name: 'test-tool',
+        content: JSON.stringify(toolResult.content)
+      })
+      expect(core.info).toHaveBeenCalledWith(
+        'Executing tool: test-tool with args: {"param": "value"}'
+      )
+      expect(core.info).toHaveBeenCalledWith(
+        'Tool test-tool executed successfully'
+      )
+    })
+
+    it('handles tool execution errors gracefully', async () => {
+      const toolCall = {
+        id: 'call-456',
+        function: {
+          name: 'failing-tool',
+          arguments: '{"param": "value"}'
+        }
+      }
+      const toolError = new Error('Tool execution failed')
+
+      mockCallTool.mockRejectedValue(toolError)
+
+      const result = await executeToolCall(mockClient, toolCall)
+
+      expect(result).toEqual({
+        tool_call_id: 'call-456',
+        role: 'tool',
+        name: 'failing-tool',
+        content: 'Error: Error: Tool execution failed'
+      })
+      expect(core.warning).toHaveBeenCalledWith(
+        'Failed to execute tool failing-tool: Error: Tool execution failed'
+      )
+    })
+
+    it('handles invalid JSON arguments', async () => {
+      const toolCall = {
+        id: 'call-789',
+        function: {
+          name: 'test-tool',
+          arguments: 'invalid-json'
+        }
+      }
+
+      const result = await executeToolCall(mockClient, toolCall)
+
+      expect(result.tool_call_id).toBe('call-789')
+      expect(result.role).toBe('tool')
+      expect(result.name).toBe('test-tool')
+      expect(result.content).toContain('Error:')
+      expect(core.warning).toHaveBeenCalledWith(
+        expect.stringContaining('Failed to execute tool test-tool:')
+      )
+    })
+  })
+
+  describe('executeToolCalls', () => {
+    it('executes multiple tool calls successfully', async () => {
+      const toolCalls = [
+        {
+          id: 'call-1',
+          function: { name: 'tool-1', arguments: '{}' }
+        },
+        {
+          id: 'call-2',
+          function: { name: 'tool-2', arguments: '{"param": "value"}' }
+        }
+      ]
+
+      mockCallTool
+        .mockResolvedValueOnce({
+          content: [{ type: 'text', text: 'Result 1' }]
+        })
+        .mockResolvedValueOnce({
+          content: [{ type: 'text', text: 'Result 2' }]
+        })
+
+      const results = await executeToolCalls(mockClient, toolCalls)
+
+      expect(results).toHaveLength(2)
+      expect(results[0].tool_call_id).toBe('call-1')
+      expect(results[1].tool_call_id).toBe('call-2')
+      expect(mockCallTool).toHaveBeenCalledTimes(2)
+    })
+
+    it('handles empty tool calls array', async () => {
+      const results = await executeToolCalls(mockClient, [])
+
+      expect(results).toHaveLength(0)
+      expect(mockCallTool).not.toHaveBeenCalled()
+    })
+
+    it('continues execution even if some tools fail', async () => {
+      const toolCalls = [
+        {
+          id: 'call-1',
+          function: { name: 'tool-1', arguments: '{}' }
+        },
+        {
+          id: 'call-2',
+          function: { name: 'tool-2', arguments: '{}' }
+        }
+      ]
+
+      mockCallTool
+        .mockResolvedValueOnce({
+          content: [{ type: 'text', text: 'Result 1' }]
+        })
+        .mockRejectedValueOnce(new Error('Tool 2 failed'))
+
+      const results = await executeToolCalls(mockClient, toolCalls)
+
+      expect(results).toHaveLength(2)
+      expect(results[0].content).toContain('Result 1')
+      expect(results[1].content).toContain('Error:')
+    })
+  })
+})

src/helpers.ts

@@ -0,0 +1,31 @@
+import * as core from '@actions/core'
+import * as fs from 'fs'
+
+/**
+ * Helper function to load content from a file or use fallback input
+ * @param filePathInput - Input name for the file path
+ * @param contentInput - Input name for the direct content
+ * @param defaultValue - Default value to use if neither file nor content is provided
+ * @returns The loaded content
+ */
+export function loadContentFromFileOrInput(
+  filePathInput: string,
+  contentInput: string,
+  defaultValue?: string
+): string {
+  const filePath = core.getInput(filePathInput)
+  const contentString = core.getInput(contentInput)
+
+  if (filePath !== undefined && filePath !== '') {
+    if (!fs.existsSync(filePath)) {
+      throw new Error(`File for ${filePathInput} was not found: ${filePath}`)
+    }
+    return fs.readFileSync(filePath, 'utf-8')
+  } else if (contentString !== undefined && contentString !== '') {
+    return contentString
+  } else if (defaultValue !== undefined) {
+    return defaultValue
+  } else {
+    throw new Error(`Neither ${filePathInput} nor ${contentInput} was set`)
+  }
+}

src/inference.ts

@@ -0,0 +1,156 @@
+import * as core from '@actions/core'
+import ModelClient, { isUnexpected } from '@azure-rest/ai-inference'
+import { AzureKeyCredential } from '@azure/core-auth'
+import { MCPClient, executeToolCalls } from './mcp.js'
+
+export interface InferenceRequest {
+  systemPrompt: string
+  prompt: string
+  modelName: string
+  maxTokens: number
+  endpoint: string
+  token: string
+}
+
+export interface InferenceResponse {
+  content: string | null
+  toolCalls?: any[]
+}
+
+/**
+ * Simple one-shot inference without tools
+ */
+export async function simpleInference(
+  request: InferenceRequest
+): Promise<string | null> {
+  core.info('Running simple inference without tools')
+
+  const client = ModelClient(
+    request.endpoint,
+    new AzureKeyCredential(request.token),
+    {
+      userAgentOptions: { userAgentPrefix: 'github-actions-ai-inference' }
+    }
+  )
+
+  const requestBody = {
+    messages: [
+      {
+        role: 'system',
+        content: request.systemPrompt
+      },
+      { role: 'user', content: request.prompt }
+    ],
+    max_tokens: request.maxTokens,
+    model: request.modelName
+  }
+
+  const response = await client.path('/chat/completions').post({
+    body: requestBody
+  })
+
+  if (isUnexpected(response)) {
+    throw new Error(
+      'An error occurred while fetching the response (' +
+        response.status +
+        '): ' +
+        response.body
+    )
+  }
+
+  const modelResponse = response.body.choices[0].message.content
+  core.info(`Model response: ${modelResponse || 'No response content'}`)
+
+  return modelResponse
+}
+
+/**
+ * MCP-enabled inference with tool execution loop
+ */
+export async function mcpInference(
+  request: InferenceRequest,
+  mcpClient: MCPClient
+): Promise<string | null> {
+  core.info('Running MCP inference with tools')
+
+  const client = ModelClient(
+    request.endpoint,
+    new AzureKeyCredential(request.token),
+    {
+      userAgentOptions: { userAgentPrefix: 'github-actions-ai-inference' }
+    }
+  )
+
+  // Start with the initial conversation
+  let messages: any[] = [
+    {
+      role: 'system',
+      content: request.systemPrompt
+    },
+    { role: 'user', content: request.prompt }
+  ]
+
+  let iterationCount = 0
+  const maxIterations = 5 // Prevent infinite loops
+
+  while (iterationCount < maxIterations) {
+    iterationCount++
+    core.info(`MCP inference iteration ${iterationCount}`)
+
+    const requestBody = {
+      messages: messages,
+      max_tokens: request.maxTokens,
+      model: request.modelName,
+      tools: mcpClient.tools
+    }
+
+    const response = await client.path('/chat/completions').post({
+      body: requestBody
+    })
+
+    if (isUnexpected(response)) {
+      throw new Error(
+        'An error occurred while fetching the response (' +
+          response.status +
+          '): ' +
+          response.body
+      )
+    }
+
+    const assistantMessage = response.body.choices[0].message
+    const modelResponse = assistantMessage.content
+    const toolCalls = assistantMessage.tool_calls
+
+    core.info(`Model response: ${modelResponse || 'No response content'}`)
+
+    messages.push({
+      role: 'assistant',
+      content: modelResponse,
+      ...(toolCalls && { tool_calls: toolCalls })
+    })
+
+    if (!toolCalls || toolCalls.length === 0) {
+      core.info('No tool calls requested, ending MCP inference loop')
+      return modelResponse
+    }
+
+    core.info(`Model requested ${toolCalls.length} tool calls`)
+
+    const toolResults = await executeToolCalls(mcpClient.client, toolCalls)
+    messages.push(...toolResults)
+
+    core.info('Tool results added, continuing conversation...')
+  }
+
+  core.warning(
+    `MCP inference loop exceeded maximum iterations (${maxIterations})`
+  )
+
+  // Return the last assistant message content
+  const lastAssistantMessage = messages
+    .slice()
+    .reverse()
+    .find((msg) => msg.role === 'assistant')
+
+  return lastAssistantMessage?.content || null
+}

src/main.ts

@@ -1,43 +1,13 @@
 import * as core from '@actions/core'
-import ModelClient, { isUnexpected } from '@azure-rest/ai-inference'
-import { AzureKeyCredential } from '@azure/core-auth'
-import { Client } from '@modelcontextprotocol/sdk/client/index.js'
-import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js'
 import * as fs from 'fs'
 import * as os from 'os'
 import * as path from 'path'
+import { connectToMCP } from './mcp.js'
+import { simpleInference, mcpInference, InferenceRequest } from './inference.js'
+import { loadContentFromFileOrInput } from './helpers.js'
 
 const RESPONSE_FILE = 'modelResponse.txt'
 
-/**
- * Helper function to load content from a file or use fallback input
- * @param filePathInput - Input name for the file path
- * @param contentInput - Input name for the direct content
- * @param defaultValue - Default value to use if neither file nor content is provided
- * @returns The loaded content
- */
-function loadContentFromFileOrInput(
-  filePathInput: string,
-  contentInput: string,
-  defaultValue?: string
-): string {
-  const filePath = core.getInput(filePathInput)
-  const contentString = core.getInput(contentInput)
-
-  if (filePath !== undefined && filePath !== '') {
-    if (!fs.existsSync(filePath)) {
-      throw new Error(`File for ${filePathInput} was not found: ${filePath}`)
-    }
-    return fs.readFileSync(filePath, 'utf-8')
-  } else if (contentString !== undefined && contentString !== '') {
-    return contentString
-  } else if (defaultValue !== undefined) {
-    return defaultValue
-  } else {
-    throw new Error(`Neither ${filePathInput} nor ${contentInput} was set`)
-  }
-}
-
 /**
  * The main function for the action.
  *
@@ -45,10 +15,8 @@ function loadContentFromFileOrInput(
  */
 export async function run(): Promise<void> {
   try {
-    // Load prompt content - required
     const prompt = loadContentFromFileOrInput('prompt-file', 'prompt')
 
-    // Load system prompt with default value
     const systemPrompt = loadContentFromFileOrInput(
       'system-prompt-file',
       'system-prompt',
@@ -64,200 +32,34 @@ export async function run(): Promise<void> {
     }
 
     const endpoint = core.getInput('endpoint')
-
-    // Get MCP server configuration
-    const mcpServerUrl = 'https://api.githubcopilot.com/mcp/'
     const enableMcp = core.getBooleanInput('enable-mcp') || false
 
-    let azureTools: any[] = []
-    let mcp: Client | null = null
+    const inferenceRequest: InferenceRequest = {
+      systemPrompt,
+      prompt,
+      modelName,
+      maxTokens,
+      endpoint,
+      token
+    }
 
-    // Connect to MCP server if enabled
-    if (enableMcp || true) {
-      core.info('Connecting to GitHub MCP server...' + token)
+    let modelResponse: string | null = null
 
-      const transport = new StreamableHTTPClientTransport(
-        new URL(mcpServerUrl),
-        {
-          requestInit: {
-            headers: {
-              Authorization: `Bearer ${token}`
-            }
-          }
-        }
-      )
+    if (enableMcp) {
+      const mcpClient = await connectToMCP(token)
 
-      mcp = new Client({
-        name: 'ai-inference-action',
-        version: '1.0.0',
-        transport
-      })
-
-      try {
-        await mcp.connect(transport)
-      } catch (mcpError) {
-        core.warning(`Failed to connect to MCP server: ${mcpError}`)
-        // Continue without tools if MCP connection fails
-        return
+      if (mcpClient) {
+        modelResponse = await mcpInference(inferenceRequest, mcpClient)
+      } else {
+        core.warning('MCP connection failed, falling back to simple inference')
+        modelResponse = await simpleInference(inferenceRequest)
       }
-
-      core.info('Successfully connected to MCP server')
-
-      // Pull tool metadata
-      const tools = await mcp.listTools()
-      core.info(`Retrieved ${tools.tools?.length || 0} tools from MCP server`)
-
-      // Map MCP → Azure tool definitions
-      azureTools = (tools.tools || []).map((t) => ({
-        type: 'function',
-        function: {
-          name: t.name,
-          description: t.description,
-          parameters: t.inputSchema
-        }
-      }))
-
-      core.info(`Mapped ${azureTools.length} tools for Azure AI Inference`)
+    } else {
+      modelResponse = await simpleInference(inferenceRequest)
     }
 
-    const client = ModelClient(endpoint, new AzureKeyCredential(token), {
-      userAgentOptions: { userAgentPrefix: 'github-actions-ai-inference' }
-    })
-
-    const requestBody: any = {
-      messages: [
-        {
-          role: 'system',
-          content: systemPrompt
-        },
-        { role: 'user', content: prompt }
-      ],
-      max_tokens: maxTokens,
-      model: modelName
-    }
-
-    // Add tools if available
-    if (azureTools.length > 0) {
-      requestBody.tools = azureTools
-    }
-
-    const response = await client.path('/chat/completions').post({
-      body: requestBody
-    })
-
-    if (isUnexpected(response)) {
-      throw new Error(
-        'An error occurred while fetching the response (' +
-          response.status +
-          '): ' +
-          response.body
-      )
-    }
-
-    let modelResponse: string | null =
-      response.body.choices[0].message.content
-
-    core.info(`Model response: ${response || 'No response content'}`)
-
-    // Handle tool calls if present
-    const toolCalls = response.body.choices[0].message.tool_calls
-    if (toolCalls && toolCalls.length > 0 && mcp) {
-      core.info(`Model requested ${toolCalls.length} tool calls`)
-      
-      // Execute tool calls via MCP and continue the conversation
-      const toolResults: any[] = []
-      
-      for (const toolCall of toolCalls) {
-        core.info(
-          `Executing tool: ${toolCall.function.name} with args: ${toolCall.function.arguments}`
-        )
-        
-        try {
-          // Parse the arguments from JSON string
-          const args = JSON.parse(toolCall.function.arguments)
-          
-          // Call the tool via MCP
-          const result = await mcp.callTool({
-            name: toolCall.function.name,
-            arguments: args
-          })
-          
-          core.info(`Tool ${toolCall.function.name} executed successfully`)
-          
-          // Store the result for the follow-up conversation
-          toolResults.push({
-            tool_call_id: toolCall.id,
-            role: 'tool',
-            name: toolCall.function.name,
-            content: JSON.stringify(result.content)
-          })
-          
-        } catch (toolError) {
-          core.warning(`Failed to execute tool ${toolCall.function.name}: ${toolError}`)
-          
-          // Add error result to continue conversation
-          toolResults.push({
-            tool_call_id: toolCall.id,
-            role: 'tool',
-            name: toolCall.function.name,
-            content: `Error: ${toolError}`
-          })
-        }
-      }
-      
-      // If we have tool results, continue the conversation
-      if (toolResults.length > 0) {
-        core.info('Continuing conversation with tool results...')
-        
-        // Build the follow-up request with the original conversation + tool results
-        const followUpMessages = [
-          {
-            role: 'system',
-            content: systemPrompt
-          },
-          { role: 'user', content: prompt },
-          {
-            role: 'assistant',
-            content: modelResponse,
-            tool_calls: toolCalls
-          },
-          ...toolResults
-        ]
-        
-        const followUpRequest: any = {
-          messages: followUpMessages,
-          max_tokens: maxTokens,
-          model: modelName
-        }
-        
-        // Add tools again for potential follow-up tool calls
-        if (azureTools.length > 0) {
-          followUpRequest.tools = azureTools
-        }
-        
-        const followUpResponse = await client.path('/chat/completions').post({
-          body: followUpRequest
-        })
-        
-        if (isUnexpected(followUpResponse)) {
-          core.warning(
-            'Failed to get follow-up response after tool execution: ' +
-            followUpResponse.status + ': ' + followUpResponse.body
-          )
-        } else {
-          const finalResponse = followUpResponse.body.choices[0].message.content
-          core.info(`Final response after tool execution: ${finalResponse}`)
-          
-          // Update the model response to the final one
-          modelResponse = finalResponse || modelResponse
-        }
-      }
-    }
-
-    // Set outputs for other workflow steps to use
     core.setOutput('response', modelResponse || '')
 
-    // Save the response to a file in case the response overflow the output limit
     const responseFilePath = path.join(tempDir(), RESPONSE_FILE)
     core.setOutput('response-file', responseFilePath)
 
@@ -265,7 +67,6 @@ export async function run(): Promise<void> {
       fs.writeFileSync(responseFilePath, modelResponse, 'utf-8')
     }
   } catch (error) {
-    // Fail the workflow run if an error occurs
     if (error instanceof Error) {
       core.setFailed(error.message)
     } else {

src/mcp.ts

@@ -0,0 +1,129 @@
+import * as core from '@actions/core'
+import { Client } from '@modelcontextprotocol/sdk/client/index.js'
+import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js'
+
+export interface ToolResult {
+  tool_call_id: string
+  role: 'tool'
+  name: string
+  content: string
+}
+
+export interface MCPClient {
+  client: Client
+  tools: any[]
+}
+
+/**
+ * Connect to the MCP server and retrieve available tools
+ */
+export async function connectToMCP(token: string): Promise<MCPClient | null> {
+  const mcpServerUrl = 'https://api.githubcopilot.com/mcp/'
+
+  core.info('Connecting to GitHub MCP server...')
+
+  const transport = new StreamableHTTPClientTransport(new URL(mcpServerUrl), {
+    requestInit: {
+      headers: {
+        Authorization: `Bearer ${token}`
+      }
+    }
+  })
+
+  const client = new Client({
+    name: 'ai-inference-action',
+    version: '1.0.0',
+    transport
+  })
+
+  try {
+    await client.connect(transport)
+  } catch (mcpError) {
+    core.warning(`Failed to connect to MCP server: ${mcpError}`)
+    return null
+  }
+
+  core.info('Successfully connected to MCP server')
+
+  // Pull tool metadata
+  const toolsResponse = await client.listTools()
+  core.info(
+    `Retrieved ${toolsResponse.tools?.length || 0} tools from MCP server`
+  )
+
+  // Map MCP → Azure tool definitions
+  const tools = (toolsResponse.tools || []).map((t) => ({
+    type: 'function',
+    function: {
+      name: t.name,
+      description: t.description,
+      parameters: t.inputSchema
+    }
+  }))
+
+  core.info(`Mapped ${tools.length} tools for Azure AI Inference`)
+
+  return { client, tools }
+}
+
+/**
+ * Execute a single tool call via MCP
+ */
+export async function executeToolCall(
+  mcpClient: Client,
+  toolCall: any
+): Promise<ToolResult> {
+  core.info(
+    `Executing tool: ${toolCall.function.name} with args: ${toolCall.function.arguments}`
+  )
+
+  try {
+    // Parse the arguments from JSON string
+    const args = JSON.parse(toolCall.function.arguments)
+
+    // Call the tool via MCP
+    const result = await mcpClient.callTool({
+      name: toolCall.function.name,
+      arguments: args
+    })
+
+    core.info(`Tool ${toolCall.function.name} executed successfully`)
+
+    // Return the result formatted for the conversation
+    return {
+      tool_call_id: toolCall.id,
+      role: 'tool',
+      name: toolCall.function.name,
+      content: JSON.stringify(result.content)
+    }
+  } catch (toolError) {
+    core.warning(
+      `Failed to execute tool ${toolCall.function.name}: ${toolError}`
+    )
+
+    // Return error result to continue conversation
+    return {
+      tool_call_id: toolCall.id,
+      role: 'tool',
+      name: toolCall.function.name,
+      content: `Error: ${toolError}`
+    }
+  }
+}
+
+/**
+ * Execute all tool calls from a response
+ */
+export async function executeToolCalls(
+  mcpClient: Client,
+  toolCalls: any[]
+): Promise<ToolResult[]> {
+  const toolResults: ToolResult[] = []
+
+  for (const toolCall of toolCalls) {
+    const result = await executeToolCall(mcpClient, toolCall)
+    toolResults.push(result)
+  }
+
+  return toolResults
+}