LSP Intelligence

The plugin integrates with nargo lsp (the Noir Language Server) to provide intelligent code assistance. This includes code completion, real-time diagnostics, navigation, hover information, and more.

Note

LSP features require nargo to be installed and accessible. See Installation for setup instructions.

Code Completion

Get context-aware suggestions as you type.

Keyboard shortcut: Ctrl+Space (or start typing after . or ::)

Code completion provides:

• Function and method names
• Struct fields
• Module members
• Import suggestions
• Local variables
• Type names

use std::hash::poseidon;

fn example() {
    // Type "pos" then Ctrl+Space to see poseidon suggestions
    let hash = poseidon::bn254::hash_1([1]);

    // After ".", completion shows available methods
    let arr = [1, 2, 3];
    let len = arr.len(); // .len() suggested after arr.
}

Diagnostics

Real-time error and warning highlighting as you type.

Diagnostics show:

• Errors (red underline) - Code that won’t compile
• Warnings (yellow underline) - Potential issues

fn diagnostics_demo() {
    let x: Field = "not a field";  // Error: type mismatch
    let unused = 5;                 // Warning: unused variable
}

Errors appear in:

• The editor (underlined)
• The gutter (red/yellow icons)
• The Problems tool window

Tip

Press F2 to jump to the next error/warning in the file.

Go to Definition

Navigate to where a symbol is defined.

Keyboard shortcut: Cmd+B (macOS) or Ctrl+B (Windows/Linux)

Also works with:

• Cmd+Click / Ctrl+Click on a symbol
• Right-click → Go to → Declaration

use std::hash::poseidon;

fn main() {
    let result = helper_function(5);  // Cmd+B here → jumps to definition
}

fn helper_function(x: Field) -> Field {
    x * 2
}

Works for:

• Functions
• Structs
• Modules
• Imported items
• Local variables

Hover Information

See type information and documentation by hovering over symbols.

Hover shows:

• Type signatures
• Function parameters
• Documentation comments
• Module paths

/// Adds two fields together
fn add(a: Field, b: Field) -> Field {
    a + b
}

fn demo() {
    let result = add(1, 2);  // Hover over "add" to see signature and docs
}

Find References

Find all usages of a symbol across your project.

Keyboard shortcut: Alt+F7 (macOS/Windows/Linux)

Also available via:

• Right-click → Find Usages
• Edit → Find → Find Usages

The References panel shows all locations where the symbol is used, organized by file.

Signature Help

See function parameter hints while typing.

Keyboard shortcut: Cmd+P (macOS) or Ctrl+P (Windows/Linux)

When typing function arguments, signature help shows:

• Parameter names and types
• Current parameter (highlighted)
• Overload information (if applicable)

fn greet(name: str<32>, times: u32) {
    // ...
}

fn demo() {
    greet( // Signature help appears here showing: name: str<32>, times: u32
        "Alice",
        3
    );
}

Code Actions

Quick fixes and refactoring suggestions.

Keyboard shortcut: Alt+Enter (when cursor is on an issue)

Also shown via the lightbulb icon in the gutter.

Code actions may include:

• Import suggestions
• Quick fixes for common errors
• Refactoring options

Note

Available code actions depend on the nargo LSP version. Update nargo to get the latest features.

Keyboard Shortcuts Summary

Action	macOS	Windows/Linux
Code Completion	Ctrl+Space	Ctrl+Space
Go to Definition	Cmd+B	Ctrl+B
Find References	Alt+F7	Alt+F7
Signature Help	Cmd+P	Ctrl+P
Code Actions	Alt+Enter	Alt+Enter
Next Error	F2	F2
Previous Error	Shift+F2	Shift+F2

Tip

These are default keymaps. Your actual shortcuts may vary if you’ve customized your keymap. Check Settings → Keymap to see or change shortcuts.

Troubleshooting LSP

If LSP features aren’t working:

1. Check nargo is installed: Run nargo --version in terminal
2. Restart LSP: Tools → Noir → Restart Language Server
3. Check settings: Ensure LSP is enabled in Settings → Languages & Frameworks → Noir
4. Check logs: Help → Show Log in Finder/Explorer and search for “Noir”

See Troubleshooting for more solutions.