feat: add support for JetBrains AI Assistant MCP configuration

.gitignore

@@ -342,6 +342,7 @@ rulesync.local.jsonc
 **/.rovodev/subagents/
 **/.takt/facets/personas/
 **/.vibe/agents/
+**/.ai/mcp/mcp.json
 **/.agents/mcp_config.json
 **/.augment/settings.json
 **/.mcp.json

README.md

@@ -113,7 +113,7 @@ The tables below show whether each tool supports a given feature (✅ = supporte
 | Kiro IDE               |  ✅   |   ✅   | ✅  |    ✅    |    ✅     |   ✅   |  ✅   |     ✅      |        |
 | Google Antigravity IDE |  ✅   |        | ✅  |    ✅    |           |   ✅   |  ✅   |     ✅      |        |
 | Google Antigravity CLI |  ✅   |   ✅   | ✅  |    ✅    |           |   ✅   |  ✅   |     ✅      |        |
-| JetBrains AI Assistant |  ✅   |   ✅   |     |          |           |   ✅   |       |             |        |
+| JetBrains AI Assistant |  ✅   |   ✅   | ✅  |          |           |   ✅   |       |             |        |
 | JetBrains Junie        |  ✅   |   ✅   | ✅  |    ✅    |    ✅     |   ✅   |  ✅   |     ✅      |        |
 | AugmentCode            |  ✅   |   ✅   | ✅  |    ✅    |    ✅     |   ✅   |  ✅   |     ✅      |        |
 | Devin Desktop          |  ✅   |   ✅   | ✅  |    ✅    |    ✅     |   ✅   |  ✅   |     ✅      |        |

docs/reference/supported-tools.md

@@ -33,7 +33,7 @@ Rulesync supports both **generation** and **import** for All of the major AI cod
 | Kiro IDE               | kiro-ide        | ✅ 🌏 |   ✅   |  ✅ 🌏   |    ✅    |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |     ✅      |        |
 | Google Antigravity IDE | antigravity-ide | ✅ 🌏 |        | ✅ 🌏 🔧 |  ✅ 🌏   |           | ✅ 🌏  | ✅ 🌏 |     ✅      |        |
 | Google Antigravity CLI | antigravity-cli | ✅ 🌏 |   ✅   | ✅ 🌏 🔧 |  ✅ 🌏   |           | ✅ 🌏  | ✅ 🌏 |     🌏      |        |
-| JetBrains AI Assistant | aiassistant     |  ✅   |   ✅   |          |          |           |   ✅   |       |             |        |
+| JetBrains AI Assistant | aiassistant     |  ✅   |   ✅   |  ✅ 🌏   |          |           |   ✅   |       |             |        |
 | JetBrains Junie        | junie           | ✅ 🌏 |   ✅   |  ✅ 🌏   |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  |  🌏   |    ✅ 🌏    |        |
 | AugmentCode            | augmentcode     | ✅ 🌏 |   ✅   |  ✅ 🌏   |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |    ✅ 🌏    |        |
 | Devin Desktop          | devin           | ✅ 🌏 |   ✅   | ✅ 🌏 🔧 |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |    ✅ 🌏    |        |

skills/rulesync/supported-tools.md

@@ -33,7 +33,7 @@ Rulesync supports both **generation** and **import** for All of the major AI cod
 | Kiro IDE               | kiro-ide        | ✅ 🌏 |   ✅   |  ✅ 🌏   |    ✅    |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |     ✅      |        |
 | Google Antigravity IDE | antigravity-ide | ✅ 🌏 |        | ✅ 🌏 🔧 |  ✅ 🌏   |           | ✅ 🌏  | ✅ 🌏 |     ✅      |        |
 | Google Antigravity CLI | antigravity-cli | ✅ 🌏 |   ✅   | ✅ 🌏 🔧 |  ✅ 🌏   |           | ✅ 🌏  | ✅ 🌏 |     🌏      |        |
-| JetBrains AI Assistant | aiassistant     |  ✅   |   ✅   |          |          |           |   ✅   |       |             |        |
+| JetBrains AI Assistant | aiassistant     |  ✅   |   ✅   |  ✅ 🌏   |          |           |   ✅   |       |             |        |
 | JetBrains Junie        | junie           | ✅ 🌏 |   ✅   |  ✅ 🌏   |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  |  🌏   |    ✅ 🌏    |        |
 | AugmentCode            | augmentcode     | ✅ 🌏 |   ✅   |  ✅ 🌏   |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |    ✅ 🌏    |        |
 | Devin Desktop          | devin           | ✅ 🌏 |   ✅   | ✅ 🌏 🔧 |  ✅ 🌏   |   ✅ 🌏   | ✅ 🌏  | ✅ 🌏 |    ✅ 🌏    |        |

src/constants/aiassistant-paths.ts

@@ -12,3 +12,9 @@ export const AIASSISTANT_IGNORE_FILE_NAME = ".aiignore";
 // directory, following the open Agent Skills standard. The relative path is the
 // same as the agentsskills target. https://agentskills.io/specification
 export const AIASSISTANT_SKILLS_DIR_PATH = AGENTSMD_SKILLS_DIR_PATH;
+// JetBrains AI Assistant project-level MCP configuration is read from
+// `.ai/mcp/mcp.json`. https://www.jetbrains.com/help/ai-assistant/mcp.html
+export const AIASSISTANT_MCP_DIR = ".ai";
+export const AIASSISTANT_MCP_SUB_DIR = "mcp";
+export const AIASSISTANT_MCP_DIR_PATH = join(AIASSISTANT_MCP_DIR, AIASSISTANT_MCP_SUB_DIR);
+export const AIASSISTANT_MCP_FILE_NAME = "mcp.json";

src/e2e/e2e-mcp.spec.ts

@@ -24,6 +24,7 @@ import {
 
 // Native MCP tools that emit "test-server" (takt writes a transport allowlist instead).
 const mcpGenerateTargets = [
+  { target: "aiassistant", outputPath: join(".ai", "mcp", "mcp.json") },
   { target: "augmentcode", outputPath: join(".augment", "settings.json") },
   { target: "amp", outputPath: join(".amp", "settings.json") },
   { target: "claudecode", outputPath: ".mcp.json" },
@@ -606,6 +607,7 @@ describe("E2E: mcp (import)", () => {
 
 // Native global-scope MCP tools that emit "test-server" (takt writes a transport allowlist instead).
 const mcpGlobalTargets = [
+  { target: "aiassistant", outputPath: join(".ai", "mcp", "mcp.json") },
   { target: "augmentcode", outputPath: join(".augment", "settings.json") },
   { target: "claudecode", outputPath: ".claude.json" },
   { target: "cursor", outputPath: join(".cursor", "mcp.json") },

src/features/mcp/aiassistant-mcp.test.ts

@@ -0,0 +1,122 @@
+import { join } from "node:path";
+
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import {
+  RULESYNC_MCP_SCHEMA_URL,
+  RULESYNC_RELATIVE_DIR_PATH,
+} from "../../constants/rulesync-paths.js";
+import { setupTestDirectory } from "../../test-utils/test-directories.js";
+import { ensureDir, writeFileContent } from "../../utils/file.js";
+import { AiassistantMcp } from "./aiassistant-mcp.js";
+import { RulesyncMcp } from "./rulesync-mcp.js";
+
+describe("AiassistantMcp", () => {
+  let testDir: string;
+  let cleanup: () => Promise<void>;
+
+  beforeEach(async () => {
+    ({ testDir, cleanup } = await setupTestDirectory());
+    vi.spyOn(process, "cwd").mockReturnValue(testDir);
+  });
+
+  afterEach(async () => {
+    await cleanup();
+    vi.restoreAllMocks();
+  });
+
+  describe("constructor", () => {
+    it("creates an instance and parses JSON", () => {
+      const validJsonContent = JSON.stringify({
+        mcpServers: {
+          "test-server": { command: "node", args: ["server.js"] },
+        },
+      });
+
+      const aiassistantMcp = new AiassistantMcp({
+        relativeDirPath: ".ai/mcp",
+        relativeFilePath: "mcp.json",
+        fileContent: validJsonContent,
+      });
+
+      expect(aiassistantMcp).toBeInstanceOf(AiassistantMcp);
+      expect(aiassistantMcp.getRelativeDirPath()).toBe(".ai/mcp");
+      expect(aiassistantMcp.getRelativeFilePath()).toBe("mcp.json");
+      expect(aiassistantMcp.getJson()).toEqual(JSON.parse(validJsonContent));
+    });
+  });
+
+  describe("fromFile", () => {
+    it("reads .ai/mcp/mcp.json from disk", async () => {
+      const dir = join(testDir, ".ai/mcp");
+      await ensureDir(dir);
+      const filePath = join(dir, "mcp.json");
+      const content = JSON.stringify({ mcpServers: { A: { command: "echo" } } }, null, 2);
+      await writeFileContent(filePath, content);
+
+      const aiassistant = await AiassistantMcp.fromFile({ outputRoot: testDir, validate: true });
+
+      expect(aiassistant.getFilePath()).toBe(filePath);
+      expect(aiassistant.getFileContent()).toBe(content);
+      expect(aiassistant.getJson()).toEqual(JSON.parse(content));
+    });
+  });
+
+  describe("getSettablePaths", () => {
+    describe("getSettablePaths", () => {
+      it("returns the same .ai/mcp/mcp.json path for project and global mode", () => {
+        const projectPaths = AiassistantMcp.getSettablePaths({ global: false });
+        const globalPaths = AiassistantMcp.getSettablePaths({ global: true });
+        const expected = { relativeDirPath: join(".ai", "mcp"), relativeFilePath: "mcp.json" };
+        expect(projectPaths).toEqual(expected);
+        expect(globalPaths).toEqual(expected);
+      });
+    });
+  });
+
+  describe("fromRulesyncMcp", () => {
+    it("copies content from .rulesync/.mcp.json", async () => {
+      const rulesyncContent = JSON.stringify(
+        { mcpServers: { B: { command: "node", args: ["b.js"] } } },
+        null,
+        2,
+      );
+      const rulesync = new RulesyncMcp({
+        outputRoot: testDir,
+        relativeDirPath: RULESYNC_RELATIVE_DIR_PATH,
+        relativeFilePath: ".mcp.json",
+        fileContent: rulesyncContent,
+      });
+
+      const aiassistant = AiassistantMcp.fromRulesyncMcp({
+        outputRoot: testDir,
+        rulesyncMcp: rulesync,
+      });
+
+      expect(aiassistant.getRelativeDirPath()).toBe(".ai/mcp");
+      expect(aiassistant.getRelativeFilePath()).toBe("mcp.json");
+      expect(aiassistant.getFileContent()).toBe(rulesyncContent);
+    });
+  });
+
+  describe("toRulesyncMcp", () => {
+    it("maps back to a RulesyncMcp with same content", () => {
+      const content = JSON.stringify({ mcpServers: { X: { command: "echo" } } }, null, 2);
+      const aiassistant = new AiassistantMcp({
+        outputRoot: testDir,
+        relativeDirPath: ".ai/mcp",
+        relativeFilePath: "mcp.json",
+        fileContent: content,
+      });
+
+      const rulesync = aiassistant.toRulesyncMcp();
+      expect(rulesync).toBeInstanceOf(RulesyncMcp);
+      expect(rulesync.getRelativeDirPath()).toBe(RULESYNC_RELATIVE_DIR_PATH);
+      expect(rulesync.getRelativeFilePath()).toBe("mcp.json");
+      expect(JSON.parse(rulesync.getFileContent())).toEqual({
+        $schema: RULESYNC_MCP_SCHEMA_URL,
+        ...JSON.parse(content),
+      });
+    });
+  });
+});

src/features/mcp/aiassistant-mcp.ts

@@ -0,0 +1,113 @@
+import { join } from "node:path";
+
+import {
+  AIASSISTANT_MCP_DIR_PATH,
+  AIASSISTANT_MCP_FILE_NAME,
+} from "../../constants/aiassistant-paths.js";
+import { ValidationResult } from "../../types/ai-file.js";
+import { readFileContent } from "../../utils/file.js";
+import { RulesyncMcp } from "./rulesync-mcp.js";
+import {
+  ToolMcp,
+  ToolMcpForDeletionParams,
+  ToolMcpFromFileParams,
+  ToolMcpFromRulesyncMcpParams,
+  ToolMcpParams,
+  ToolMcpSettablePaths,
+} from "./tool-mcp.js";
+
+export class AiassistantMcp extends ToolMcp {
+  private readonly json: Record<string, unknown>;
+
+  constructor(params: ToolMcpParams) {
+    super(params);
+    this.json = this.fileContent !== undefined ? JSON.parse(this.fileContent) : {};
+  }
+
+  getJson(): Record<string, unknown> {
+    return this.json;
+  }
+
+  static getSettablePaths(_options: { global?: boolean } = {}): ToolMcpSettablePaths {
+    // JetBrains AI Assistant reads project-level MCP config from
+    // `.ai/mcp/mcp.json` and global (user-level) config from
+    // `~/.ai/mcp/mcp.json`. The relative path is identical for both scopes;
+    // the base directory changes (cwd for project, home dir for global).
+    return {
+      relativeDirPath: AIASSISTANT_MCP_DIR_PATH,
+      relativeFilePath: AIASSISTANT_MCP_FILE_NAME,
+    };
+  }
+
+  static async fromFile({
+    outputRoot = process.cwd(),
+    validate = true,
+    global = false,
+  }: ToolMcpFromFileParams): Promise<AiassistantMcp> {
+    const paths = this.getSettablePaths({ global });
+    const fileContent = await readFileContent(
+      join(outputRoot, paths.relativeDirPath, paths.relativeFilePath),
+    );
+
+    return new AiassistantMcp({
+      outputRoot,
+      relativeDirPath: paths.relativeDirPath,
+      relativeFilePath: paths.relativeFilePath,
+      fileContent,
+      validate,
+      global,
+    });
+  }
+
+  static fromRulesyncMcp({
+    outputRoot = process.cwd(),
+    rulesyncMcp,
+    validate = true,
+    global = false,
+  }: ToolMcpFromRulesyncMcpParams): AiassistantMcp {
+    const paths = this.getSettablePaths({ global });
+
+    // Preserve top-level fields ($schema, etc.) from the source JSON, but
+    // use getMcpServers() so rulesync-only fields and codex-only fields
+    // (`envVars`) are stripped before writing the aiassistant config.
+    const json = rulesyncMcp.getJson();
+    const fileContent = JSON.stringify(
+      { ...json, mcpServers: rulesyncMcp.getMcpServers() },
+      null,
+      2,
+    );
+
+    return new AiassistantMcp({
+      outputRoot,
+      relativeDirPath: paths.relativeDirPath,
+      relativeFilePath: paths.relativeFilePath,
+      fileContent,
+      validate,
+      global,
+    });
+  }
+
+  toRulesyncMcp(): RulesyncMcp {
+    return this.toRulesyncMcpDefault();
+  }
+
+  validate(): ValidationResult {
+    return { success: true, error: null };
+  }
+
+  static forDeletion({
+    outputRoot = process.cwd(),
+    relativeDirPath,
+    relativeFilePath,
+    global = false,
+  }: ToolMcpForDeletionParams): AiassistantMcp {
+    return new AiassistantMcp({
+      outputRoot,
+      relativeDirPath,
+      relativeFilePath,
+      fileContent: "{}",
+      validate: false,
+      global,
+    });
+  }
+}

src/features/mcp/mcp-processor.ts

@@ -8,6 +8,7 @@ import { mcpProcessorToolTargetTuple } from "../../types/tool-target-tuples.js";
 import { ToolTarget } from "../../types/tool-targets.js";
 import { formatError } from "../../utils/error.js";
 import type { Logger } from "../../utils/logger.js";
+import { AiassistantMcp } from "./aiassistant-mcp.js";
 import { AmpMcp } from "./amp-mcp.js";
 import { AntigravityCliMcp } from "./antigravity-cli-mcp.js";
 import { AntigravityIdeMcp } from "./antigravity-ide-mcp.js";
@@ -85,6 +86,23 @@ type ToolMcpFactory = {
  * Using Map to preserve insertion order for consistent iteration.
  */
 export const toolMcpFactories = new Map<McpProcessorToolTarget, ToolMcpFactory>([
+  [
+    "aiassistant",
+    {
+      // JetBrains AI Assistant reads project-level MCP config from
+      // `.ai/mcp/mcp.json` and global (user-level) config from
+      // `~/.ai/mcp/mcp.json`. The relative path is identical for both scopes;
+      // the base directory changes (cwd for project, home dir for global).
+      // https://www.jetbrains.com/help/ai-assistant/mcp.html
+      class: AiassistantMcp,
+      meta: {
+        supportsProject: true,
+        supportsGlobal: true,
+        supportsEnabledTools: false,
+        supportsDisabledTools: false,
+      },
+    },
+  ],
   [
     "amp",
     {

src/types/tool-target-tuples.ts

@@ -64,6 +64,7 @@ export const ignoreProcessorToolTargetTuple = [
 ] as const;
 
 export const mcpProcessorToolTargetTuple = [
+  "aiassistant",
   "amp",
   "antigravity-cli",
   "antigravity-ide",