Proposal: Expose LSP/Language Service capabilities (e.g., rename) via a tsc subcommand

### 🔍 Search Terms

lsp rename refactor

### ✅ Viability Checklist

- [x] This wouldn't be a breaking change in existing TypeScript/JavaScript code
- [x] This wouldn't change the runtime behavior of existing JavaScript code
- [x] This could be implemented without emitting different JS based on the types of the expressions
- [x] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
- [x] This isn't a request to add a new utility type: https://github.com/microsoft/TypeScript/wiki/No-New-Utility-Types
- [x] This feature would agree with the rest of our Design Goals: https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals

### ⭐ Suggestion

As AI coding agents evolve, structured program manipulation becomes increasingly vital. While tsc currently excels at type-checking and emitting JavaScript, programmatic refactoring (such as symbol renaming) is only exposed through the Language Service API in Node.js or via standard LSP integration over IPC.

To better support CLI-driven agent workflows, we should consider exposing core Language Service features through dedicated tsc subcommands (e.g., tsc rename ).

Prior Art / Motivation:
Other language toolchains already offer similar CLI interfaces for headless program transformation. For instance, Go provides native subcommand/tooling support via gopls (e.g., gopls rename ...), allowing external CLI tools and AI agents to execute deterministic, workspace-wide symbol renames without needing to boot a full LSP client or write custom Node.js wrappers around typescript.createLanguageService.

Exposing this in tsc would provide:

A standardized, zero-dependency CLI interface for AI agents to perform refactoring safely.

Deterministic AST/type-aware renaming out of the box for automated workflows.

Reduced friction for CLI tool developers who currently have to mock or bridge LSP protocols.

### 📃 Motivating Example

```
$ gopls rename --help
rename selected identifier

Usage:
gopls [flags] rename [rename-flags]

Example:

$ # 1-based location (:line:column or :#position) of the thing to change
$ gopls rename helper/helper.go:8:6 Foo
$ gopls rename helper/helper.go:#53 Foo

rename-flags:
-d,-diff
display diffs instead of edited file content
-l,-list
display names of edited files
-preserve
with -write, make copies of original files
-w,-write
write edited content to source files
```

### 💻 Use Cases

1. agent vibe coding

まず既存の tsc CLI のインターフェースと Language Service API を確認し、説明されている gopls の rename インターフェースを先行事例として使用します。実装前に、コマンドの形、サポートする機能、workspace/edit の出力動作を定義します。完了条件は、決定論的な CLI リファクタリングワークフローについて合意されたスコープが定まることです。

索引モデルが issue の本文から書いたものです。