@coderover/mcp-typescript

Real TypeScript grammar support for @coderover/mcp. One install, nothing to configure.

npm install @coderover/mcp-typescript

This pulls in both @coderover/mcp (the MCP server + CLI) and tree-sitter-typescript (the real TS grammar, including the tsx dialect). After install, local-mode indexing parses .ts / .tsx / .mts / .cts files with the proper grammar — type annotations, interface, type, generics, decorators, and JSX all parse cleanly instead of degrading through the JS-fallback grammar.

Why this matters

Through 0.4.x, local mode used tree-sitter-javascript for both JS and TS. That grammar is TS-tolerant — it parses many TS files without crashing — but it can't actually understand TS-only constructs. Functions with return types (function foo(): Promise<T>), interfaces, type aliases, generics on functions, etc. all wind up under hasError nodes, so the chunker drops them and find_symbol can't see them.

Concretely, the 0.4.0 evaluation against this fixture:

export interface User { id: string; }
export async function findUser(id: string): Promise<User | null> { ... }
export function retryOn429<T>(fn: () => Promise<T>): Promise<T> { ... }

…showed find_symbol("User"), find_symbol("findUser"), and find_symbol("retryOn429") all returning 0 results, because the JS grammar gave up on every line with a type annotation.

Installing @coderover/mcp-typescript flips @coderover/mcp over to the real grammar. Same fixture, after this companion is installed: all three symbols index correctly.

Why a separate package?

tree-sitter-typescript is ~38 MB unpacked — a precompiled native parser (per platform) plus the grammar artifacts for both the typescript and tsx dialects. Adding 38 MB to every @coderover/mcp install would undo the install-bloat win 0.3.0 got from splitting out @coderover/mcp-offline. Pure-JS users, remote-mode users, and Python/Go/Java-only users never need TS grammar; only the TS-heavy codebases do.

Splitting it out means:

• Default @coderover/mcp install stays small. No 38 MB grammar tax for users who don't need it.
• TS users install one package, get full coverage. No flags, no env vars — @coderover/mcp probes for tree-sitter-typescript at boot and prefers it for .ts files when present.
• Per-platform native builds happen at install of this package, not on every @coderover/mcp install.

What this package exports

Effectively nothing runtime-callable. The purpose is the dependency graph: having @coderover/mcp-typescript installed means tree-sitter-typescript is on the resolution path, and @coderover/mcp's lazy require('tree-sitter-typescript') succeeds.

// If you ever need it:
const { version } = require('@coderover/mcp-typescript');

That's the whole surface. Everything you'd actually call lives in @coderover/mcp.

Compatibility

| @coderover/mcp-typescript | @coderover/mcp | Notes | | --------------------------- | ---------------- | -------------------------------------------------------------------------------------------------- | | 0.1.x | ^0.5.0 | First release. 0.5.0 added the loader hook; older @coderover/mcp versions can't see this companion. |

Verifying the wiring

coderover doctor

The doctor command reports [ts-grammar] @coderover/mcp-typescript detected when the companion is installed and the loader is using it for .ts files. Without the companion, doctor logs [ts-grammar] tree-sitter-typescript not installed; using JS-grammar fallback (install @coderover/mcp-typescript for full TS coverage).

License

MIT — same as @coderover/mcp.