/install-lsps

name: install-lsps
description: Install language servers (gopls, typescript-language-server, pyright, rust-analyzer) and their prerequisite toolchains (Go, Node/npm, rustup) so the lsp tool works. Use when the user asks to enable or install LSP / language-server support, when lsp_enable reports a missing toolchain, or when the lsp tool reports no language server is installed.

Install LSPs

Enable the `lsp` tool for a language by installing its language server — and, when the server install needs it, the underlying toolchain.

Rules

• Everything here is consent-gated: only act on the user's explicit go-ahead,

and confirm each toolchain install separately — those are system-level changes, not part of whatever task prompted this.

• If the user declines, stop. If they ask not to be offered again, call

`lsp_enable` with `{"language": "<language>", "action": "dismiss"}`.

• Prefer the `lsp_enable` tool over bash whenever the toolchain already

exists; reach for bash only for the prerequisites `lsp_enable` refuses to install itself.

Per language

Work the ladder for each language the user wants:

1. **Check what is missing.** Server binaries: `gopls`, `typescript-language-server`, `pyright-langserver` (or `basedpyright-langserver`), `rust-analyzer` — also look in `~/go/bin` and `~/.cargo/bin`, which the lsp tool searches even when they are off PATH. Toolchains: `go`, `npm`, `rustup`. 2. **Toolchain present** → call `lsp_enable` with `{"language": "<go|typescript|python|rust>"}` and you are done; it runs the right server install and verifies the binary resolves. 3. **Toolchain missing** → show the user the command you intend to run, get their confirmation, run it in bash, then return to step 2. 4. **Verify** with a real `lsp` query (`documentSymbol` on an actual source file). The first query per workspace can take up to a minute while the server indexes; that is normal.

Toolchain installs (step 3 reference)

Go (for gopls):

brew install go            # macOS
sudo apt-get install -y golang-go   # Debian/Ubuntu; or dnf install golang

Or the official downloads at https://go.dev/dl for anything else.

Node/npm (for typescript-language-server and pyright):

brew install node          # macOS
sudo apt-get install -y nodejs npm  # Debian/Ubuntu

Or nvm (https://github.com/nvm-sh/nvm) when the user prefers per-user installs.

rustup (for rust-analyzer):

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

This is the official rust installer; show the user the command before running it and follow its printed PATH instructions afterwards.

Notes

• `go install` drops gopls in `~/go/bin` and rustup drops rust-analyzer in

`~/.cargo/bin`. The lsp tool finds both without PATH changes; other tools may still want a PATH entry.

• All of this can also happen at install time:

`npx @weave-os/router --pi --lsp go,typescript,python,rust`.