fix: make mex sync tool-agnostic by theDakshJaitly · Pull Request #30 · theDakshJaitly/mex

theDakshJaitly · 2026-04-13T13:01:10Z

Summary

Closes #29

mex sync no longer hardcodes Claude Code as the only AI tool
Tool selection from mex setup is now persisted to .mex/config.json
Sync dispatches to the correct CLI based on saved config (claude, opencode run, codex)
Tools without a CLI (Cursor, Windsurf, Copilot) gracefully fall back to "show prompts" mode
If multiple CLI tools are configured, user is prompted to pick one

Test plan

All 94 existing + new tests pass
Build succeeds
Run mex setup and select OpenCode → verify .mex/config.json has "aiTools": ["opencode"]
Run mex sync → verify it shows "OpenCode" in the menu instead of "Claude"
Run mex setup with multiple tools → verify sync lets you pick between them
Run mex sync with no CLI tool configured → verify it falls back to prompts mode

Closes #29 - Add AiTool type and AI_TOOLS registry with CLI metadata per tool - Persist tool selection from setup to .mex/config.json - Load saved aiTools in findConfig and pass through MexConfig - Sync now dispatches to the correct CLI (claude, opencode run, codex) - Tools without a CLI (Cursor, Windsurf, Copilot) fall back to prompts mode - Replace hardcoded "Claude" strings in sync UI and cli help text - Add tests for config persistence (save/load aiTools)

Copilot

Pull request overview

This PR makes mex sync tool-agnostic by persisting the user’s AI tool selection from mex setup and dispatching sync to the correct CLI tool (or falling back to prompt-only mode when no supported CLI is available), addressing Issue #29.

Changes:

Add persisted AI tool selection (aiTools) to the mex config model and save/load it via .mex/config.json.
Update mex sync to select an installed CLI tool from the configured set and run it interactively, otherwise fall back to “show prompts”.
Add/extend tests for config persistence and update CLI help text to remove Claude-specific wording.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
test/config.test.ts	Adds tests for loading/saving persisted `aiTools` selection.
src/types.ts	Introduces `AiTool`/`AI_TOOLS` metadata and extends `MexConfig` with `aiTools`.
src/sync/index.ts	Implements tool selection + dispatch to the selected tool’s CLI (or prompt fallback).
src/setup/index.ts	Persists tool choice from setup into mex config.
src/config.ts	Loads/saves `aiTools` from a persisted JSON config file.
src/cli.ts	Updates command help text to be tool-agnostic (“AI” vs “Claude”).

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Copilot · 2026-04-13T13:06:04Z

+  aiTools?: AiTool[];
+}
+
+function loadAiTools(scaffoldRoot: string): AiTool[] {
+  const configPath = resolve(scaffoldRoot, CONFIG_FILE);
+  if (!existsSync(configPath)) return [];
+  try {
+    const raw = JSON.parse(readFileSync(configPath, "utf-8")) as MexPersistedConfig;
+    return Array.isArray(raw.aiTools) ? raw.aiTools : [];


loadAiTools() only checks that aiTools is an array, but doesn’t validate each entry. If config.json contains an unknown string (or non-string), later code like AI_TOOLS[t] in sync can be undefined and cause a runtime crash when reading meta.cli. Consider filtering to known tools (e.g., Object.keys(AI_TOOLS)) and dropping invalid entries when loading.

Suggested change

aiTools?: AiTool[];

}

function loadAiTools(scaffoldRoot: string): AiTool[] {

const configPath = resolve(scaffoldRoot, CONFIG_FILE);

if (!existsSync(configPath)) return [];

try {

const raw = JSON.parse(readFileSync(configPath, "utf-8")) as MexPersistedConfig;

return Array.isArray(raw.aiTools) ? raw.aiTools : [];

aiTools?: unknown;

}

function isAiTool(value: unknown): value is AiTool {

return typeof value === "string";

}

function loadAiTools(scaffoldRoot: string): AiTool[] {

const configPath = resolve(scaffoldRoot, CONFIG_FILE);

if (!existsSync(configPath)) return [];

try {

const raw = JSON.parse(readFileSync(configPath, "utf-8")) as MexPersistedConfig;

return Array.isArray(raw.aiTools) ? raw.aiTools.filter(isAiTool) : [];

Copilot · 2026-04-13T13:06:04Z

+const CONFIG_FILE = "config.json";
+
+interface MexPersistedConfig {
+  aiTools?: AiTool[];
+}
+
+function loadAiTools(scaffoldRoot: string): AiTool[] {
+  const configPath = resolve(scaffoldRoot, CONFIG_FILE);
+  if (!existsSync(configPath)) return [];
+  try {
+    const raw = JSON.parse(readFileSync(configPath, "utf-8")) as MexPersistedConfig;


Config persistence is resolved relative to scaffoldRoot (resolve(scaffoldRoot, "config.json")). When findScaffoldRoot() returns projectRoot (the context/ layout), this becomes <projectRoot>/config.json, which is a very generic filename and can easily collide with an app’s own config.json (and it also differs from the PR description of .mex/config.json). Consider always reading/writing under a mex-specific path (e.g. <projectRoot>/.mex/config.json or a hidden mex-specific filename) regardless of scaffold layout.

Copilot · 2026-04-13T13:06:05Z

+export function saveAiTools(scaffoldRoot: string, tools: AiTool[]): void {
+  const configPath = resolve(scaffoldRoot, CONFIG_FILE);
+  let existing: MexPersistedConfig = {};
+  if (existsSync(configPath)) {
+    try {
+      existing = JSON.parse(readFileSync(configPath, "utf-8")) as MexPersistedConfig;
+    } catch { /* start fresh */ }
+  }
+  existing.aiTools = tools;
+  mkdirSync(dirname(configPath), { recursive: true });
+  writeFileSync(configPath, JSON.stringify(existing, null, 2) + "\n");


saveAiTools() assumes JSON.parse() returns an object. If config.json is valid JSON but not an object (e.g. an array/number/string), existing.aiTools = tools will throw at runtime. Consider guarding existing to a plain object (non-null, typeof object, not Array) before assigning, and also consider de-duplicating tools to avoid repeated entries from multi-select input.

Copilot · 2026-04-13T13:06:05Z

+function hasCliTool(cmd: string): boolean {
+  try {
+    execSync(`which ${cmd}`, { stdio: "ignore" });
+    return true;
+  } catch {
+    return false;
+  }
+}


hasCliTool() uses execSync(which ${cmd}), which is shell-based and not portable (e.g. Windows typically uses where). Even though cmd currently comes from constants, using execFileSync/spawnSync with shell:false (and selecting which vs where by platform) would make this safer and more reliable across environments.

Copilot · 2026-04-13T13:06:05Z

+  // Persist tool selection
+  if (selectedTools.length > 0 && !dryRun) {
+    const mexDir = resolve(projectRoot, ".mex");
+    saveAiTools(mexDir, selectedTools);
+  }
+
  return selectedClaude;


MexConfig now requires aiTools, but later in this file the config object passed into runScan is still created as { projectRoot, scaffoldRoot: mexDir } (missing aiTools), which will fail npm run typecheck and makes the types inconsistent. Consider including aiTools there (e.g. selectedTools/[]) or changing runScan to accept a narrower config type if it only needs projectRoot.

Copilot AI review requested due to automatic review settings April 13, 2026 13:01

Copilot started reviewing on behalf of theDakshJaitly April 13, 2026 13:01 View session

theDakshJaitly added 2 commits April 13, 2026 18:35

fix: add missing aiTools field to MexConfig in setup scanner call

3a53d7c

theDakshJaitly force-pushed the fix/29-sync-tool-agnostic branch from af89487 to 3a53d7c Compare April 13, 2026 13:05

Copilot AI reviewed Apr 13, 2026

View reviewed changes

fix: validate and deduplicate aiTools when loading/saving config

8dc953c

theDakshJaitly merged commit de1e9c5 into main Apr 13, 2026
3 checks passed

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fix: make mex sync tool-agnostic#30

fix: make mex sync tool-agnostic#30
theDakshJaitly merged 3 commits intomainfrom
fix/29-sync-tool-agnostic

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theDakshJaitly commented Apr 13, 2026

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