---
title: Using LSP servers with {% data variables.copilot.copilot_cli %}
shortTitle: LSP servers
allowTitleToDifferFromFilename: true
intro: 'LSP servers give {% data variables.copilot.copilot_cli_short %} precise code intelligence, enabling it to navigate definitions, find references, and rename symbols accurately across your project.'
versions:
  feature: copilot
contentType: concepts
docsTeamMetrics:
  - copilot-cli
category:
  - Learn about Copilot # Copilot discovery page
  - Learn about Copilot CLI # Copilot CLI bespoke page
---

## Introduction

The Language Server Protocol (LSP) is an open standard used for communication between a code editor and a language server. A language server is a process that provides language-specific features like go-to-definition and renaming a code symbol across your codebase. An "LSP server" is any language server that supports the Language Server Protocol.

{% data variables.copilot.copilot_cli %} can use LSP servers to understand the structure of your code more precisely. By adding and configuring an LSP server for each programming language in your project, you'll give {% data variables.copilot.copilot_cli_short %} a better understanding of your code.

## Benefits of LSP servers

* **Accuracy**: Results come from the language's own compiler/analyzer, providing an understanding of the structure of your code. This improves {% data variables.product.prodname_copilot_short %}'s precision when it works with your code. For example, when {% data variables.product.prodname_copilot_short %} can use "go to definition" it will find the actual definition, not a text match that looks similar.
* **Token efficiency**: Operations like "list all symbols" or "find references" return compact structured results instead of requiring the agent to read entire files into the conversation.
* **Safe refactoring**: When you rename a symbol, the LSP server reliably updates every reference across the project.
* **Speed**: Language servers index your project in the background, allowing near-instant responses.

## What LSP servers allow {% data variables.copilot.copilot_cli_short %} to do

When LSP servers are available, {% data variables.copilot.copilot_cli_short %} uses them automatically. You don't need to explicitly request it. {% data variables.copilot.copilot_cli_short %} will use an LSP server rather than text-based search whenever it can access an LSP server for the programming language you're using.

The following language server operations are supported:

| Operation | What it does |
|-----------|-------------|
| Go to definition | Jumps to where a symbol (function, class, variable) is defined. |
| Find references | Finds every location where a symbol is used. |
| Hover | Retrieves type information and documentation for a symbol. |
| Rename | Renames a symbol across the entire project, updating all references. |
| Document symbols | Lists all symbols defined in a file. |
| Workspace symbol search | Searches for symbols by name across the project. |
| Go to implementation | Finds implementations of an interface or abstract method. |
| Incoming calls | Shows which functions call a given function. |
| Outgoing calls | Shows which functions a given function calls. |

{% data variables.product.prodname_copilot_short %} selects the most appropriate LSP operation based on your prompt. For example, if you ask "where is `handlePayment` defined?", {% data variables.product.prodname_copilot_short %} will use the go-to-definition operation.

## How to add an LSP server

For {% data variables.copilot.copilot_cli_short %} to be able to use an LSP server, you must first install the server software on your local machine and then configure it in one of the configuration files that {% data variables.copilot.copilot_cli_short %} reads on startup. See [AUTOTITLE](/copilot/how-tos/copilot-cli/set-up-copilot-cli/add-lsp-servers).

An LSP server may also be added as part of a CLI plugin that you choose to install. A plugin might include an LSP server if, for example, it's designed to work with an uncommon programming language or a framework-specific file type. LSP servers included as part of a plugin are automatically available when you install the plugin—no additional configuration is needed. If you uninstall the plugin, the LSP server is removed. For more information, see [AUTOTITLE](/copilot/concepts/agents/copilot-cli/about-cli-plugins).

## How LSP servers are loaded

When {% data variables.copilot.copilot_cli %} starts, it loads LSP server configurations from multiple sources with the following priority (highest to lowest):

1. **Project config**: `.github/lsp.json` in the current repository.
1. **Plugin configs**: language servers provided by installed plugins.
1. **User config**: `~/.copilot/lsp-config.json`.

Higher-priority configurations override lower-priority ones with the same server name. This means a project can customize or disable language servers for all contributors.

Once the working directory is trusted, {% data variables.copilot.copilot_cli_short %} automatically starts any LSP servers that are relevant to your project, in the background, so they are ready to respond immediately when needed.

## Next steps

* [AUTOTITLE](/copilot/how-tos/copilot-cli/set-up-copilot-cli/add-lsp-servers)

## Further reading

* [Language Server Protocol](https://microsoft.github.io/language-server-protocol/) on the Microsoft website
* [AUTOTITLE](/copilot/reference/cli-command-reference)