pi TypeScript LSP extension

High-level TypeScript language-server tools for coding agents.

Agents usually work with files, symbols, tasks, and edits—not editor cursor offsets. This extension wraps TypeScript LSP features into a small tool set for semantic code work:

• find/understand symbols
• check TypeScript errors
• fix or organize imports
• rename symbols safely

Use normal filesystem tools (read, edit, bash/rg/find) for file discovery, text search, docs, config, and surgical edits. Use LSP tools when TypeScript semantics matter.

Installation

From npm:

pi install npm:pi-typescript-lsp

From GitHub:

pi install git:git@github.com:IbrahimMohammed47/pi-typescript-lsp.git

Manual development install:

mkdir -p ~/.pi/agent/extensions
cd ~/.pi/agent/extensions
git clone git@github.com:IbrahimMohammed47/pi-typescript-lsp.git pi-typescript-lsp
cd pi-typescript-lsp
npm install

Reload running pi session after install/update:

/reload

Tools

ts_symbol_context

Understand known TS/JS symbol. Defaults to hover/type info + definition. Add references, implementations, type definition, or call hierarchy only when needed.

{ "target": { "file": "src/auth.ts", "symbol": "getAccessToken" } }

{
  "target": { "file": "src/auth.ts", "symbol": "getAccessToken" },
  "include": { "references": true, "hover": false, "definition": false }
}

{
  "target": { "query": "CacheStore" },
  "include": { "implementation": true }
}

If multiple candidates return, retry with selectIndex.

ts_find_symbols

Language-aware symbol search or file outline.

{ "query": "SessionManager", "limit": 20 }

{ "file": "src/router.ts" }

Not for filename or plain text search; use rg/filesystem tools.

ts_errors_check

Check TypeScript errors. Pass file for recent/known changes; omit for project check.

{ "file": "src/session.ts" }

{ "maxErrors": 50 }

With file, extension checks file diagnostics first, then project typecheck if file is clean. Project check uses npm run typecheck when available, otherwise bundled tsc --noEmit --pretty false. Output is capped by maxErrors (default 20).

ts_import_fix

Fix imports in one TS/JS file via LSP code actions.

{ "file": "src/session.ts", "diagnosticIndex": 0 }

{ "file": "src/session.ts", "diagnosticIndex": 0, "applyIndex": 0 }

{ "file": "src/session.ts", "diagnosticIndex": 0, "applyIndex": 0, "apply": true }

Organize imports by omitting diagnosticIndex:

{ "file": "src/session.ts", "apply": true }

Previews by default; writes only with apply: true.

ts_rename

Safely rename symbol across files.

{
  "target": { "file": "src/auth.ts", "symbol": "getAccessToken" },
  "newName": "readAccessToken"
}

{
  "target": { "file": "src/auth.ts", "symbol": "getAccessToken" },
  "newName": "readAccessToken",
  "apply": true
}

Prefer over manual search/replace for symbol renames.

Automatic diagnostics

After successful native write or edit calls on TS/JS source files, extension can run same checks as ts_errors_check: edited file first, then project typecheck if clean.

Controlled by config.

/lsp command and config

/lsp is read-only. It shows current config, defaults, option docs, default sources, and example override file.

Project override file:

.pi/typescript-lsp.json

Defaults come from:

1. built-ins
2. nearest tsconfig.json, jsconfig.json, or tsconfig.*.json (exclude only)
3. project-local node_modules/.bin/typescript-language-server, when found
4. .pi/typescript-lsp.json, when present

Example:

{
  "enabled": true,
  "autoDiagnostics": true,
  "autoDiagnosticsWaitMs": 800,
  "maxFileSizeBytes": 2097152,
  "serverPath": "auto",
  "exclude": ["node_modules", "dist", "build", "coverage"]
}

Same example: examples/typescript-lsp.json.

Config options

• enabled (boolean, default true): master switch for tools and automatic diagnostics.
• autoDiagnostics (boolean, default true): append diagnostics after successful native write/edit calls.
• autoDiagnosticsWaitMs (number, default 800): wait time before project typecheck fallback.
• maxFileSizeBytes (number, default 2097152): max file size opened by LSP client.
• serverPath (string, default "auto"): bundled server by default; relative/absolute override allowed.
• exclude (string[]): ignored paths/globs for discovery and automatic diagnostics. Override replaces current exclude.

Development

Dependencies:

• typescript-language-server
• typescript

Reinstall if needed:

cd ~/.pi/agent/extensions/pi-typescript-lsp
npm install

Checks:

npm run typecheck
npm test
npm run pack:dry-run

Notes and limitations

• Server starts lazily on first LSP tool call.
• Server root is current pi working directory.
• File paths can be absolute or relative to pi cwd.
• Documents sync from disk before symbol/file requests.
• Files larger than maxFileSizeBytes are rejected.
• Server shuts down on pi session shutdown/reload, with kill fallback.
• Workspace symbol search depends on TypeScript server indexing/warmup; fallback scan opens likely source files.
• Project typecheck can be slow on large repositories.
• JavaScript projects work best with jsconfig.json.
• Text search is intentionally out of scope; use rg/filesystem tools.

Good agent behavior

Good:

Use ts_symbol_context for getAccessToken in src/auth.ts to understand type/definition.
Use ts_symbol_context include.references=true to find semantic usages before changing behavior.
Use ts_errors_check with changed file after TS edits to catch local and downstream errors.

Avoid:

Use LSP to search all files containing "token".

Use rg/filesystem tools for broad text search.

License

MIT. See LICENSE.