gram-lsp

Rust Language Server Protocol implementation for Gram (.gram) files in the tree-sitter-gram workspace. Parsing and diagnostics are provided by gram-data; gram-lsp handles the LSP wire protocol only.

Features

• stdio LSP — diagnostics, hover, go to definition, find references, basic completions.
• Semantic checks — duplicate named element definitions inside a subject_pattern_elements list (per spec).

To validate .gram files from the command line, use gram lint (gram check is a legacy alias). gram-lsp focuses purely on the language server.

Build

From the repository root:

cargo build --release -p gram-lsp

The binary is target/release/gram-lsp (debug: target/debug/gram-lsp).

Install it with:

cargo install --path tools/lsp/

Run

gram-lsp stdio

Editors should launch this command and speak LSP over the process stdin/stdout. The server uses UTF-8 sources and UTF-16 positions on the wire, as required by LSP.

Tests

cargo test -p gram-lsp
cargo clippy -p gram-lsp --all-targets -- -D warnings

Zed

The Gram Zed extension (editors/zed/; editors/zed/README.md) starts gram-lsp stdio. Unless you override the binary in Zed settings (see below), the extension uses gram-lsp on PATH if worktree.which finds it; otherwise it downloads gram-lsp-{target}.tar.gz from the GitHub release tagged v + extension.toml version, built by gram-lsp-release-assets.yml.

The extension manifest declares download_file and process:exec for that flow. If you restrict extension capabilities, allow download_file for github.com under gram-data/tree-sitter-gram.

Optional: custom binary path

If gram-lsp is not on PATH, point Zed at it in ~/.config/zed/settings.json (macOS), $XDG_CONFIG_HOME/zed/settings.json (Linux), or .zed/settings.json:

{
  "lsp": {
    "gram-lsp": {
      "binary": {
        "path": "/absolute/path/to/tree-sitter-gram/target/release/gram-lsp",
        "arguments": ["stdio"]
      }
    }
  }
}

The key under "lsp" must match the language server id in extension.toml (gram-lsp). If another extension registers servers for Gram, you can order or disable them with languages.Gram.language_servers; see Configuring languages | Zed.

Open a .gram file and use Zed: open LSP logs if diagnostics or hover do not appear.

See also

• Spec: specs/006-gram-lsp/spec.md
• Quickstart: specs/006-gram-lsp/quickstart.md
• CLI tool: tools/gram/ (gram check, gram extension)