> AI agents: For documentation discovery and navigation, see [llms.txt](/llms.txt).

# Tools and context reference

Look up common tool names and context references for chat prompts in Visual Studio Code. For instructions on selecting tools, invoking them, and managing approvals, see [Use tools with agents](/docs/agents/run/tools.md).

## Reference types and availability

The `#` picker includes references that serve different purposes:

* **Tools** perform actions, such as reading a file or running a command. For example, `#search/textSearch` searches file contents.
* **Context items** supply information to a prompt without asking the agent to perform an action. For example, `#selection` adds the selected editor text.

Available references depend on your harness, enabled extensions, and session capabilities. Type `#` in the chat input to see the current list. Extensions and MCP servers can provide additional tools beyond those listed here.

User-defined tool sets are deprecated and are not supported in the Copilot harness. To replace an existing tool-set file, follow [Replace tool sets](/docs/agent-customization/migrate-customizations.md#replace-tool-sets). This does not remove tool groups in the **Tools** tab or supported built-in aliases.

Referencing a tool does not bypass its [approval and permission controls](/docs/agents/run/approvals.md).

<a name="tools-and-tool-sets"></a>

## Tools

The following tables use Local harness tool reference names. Do not assume that these identifiers map directly to Copilot harness tools. In a Copilot session, use the **Tools** tab to [review the available tools](/docs/agents/run/tools.md#manage-available-tools).

### Read and search workspace files

| Reference | Purpose |
|---|---|
| `#read/readFile` | Read a file. |
| `#read/problems` | Get diagnostics from the **Problems** panel. |
| `#search/changes` | List source control changes. |
| `#search/codebase` | Find relevant code with workspace code search. |
| `#search/fileSearch` | Find files by a glob pattern. |
| `#search/listDirectory` | List directory contents. |
| `#search/textSearch` | Find text in files. |
| `#search/usages` | Find references, implementations, and definitions of symbols. |

### Edit files and work with notebooks

| Reference | Purpose |
|---|---|
| `#edit/createDirectory` | Create a directory. |
| `#edit/createFile` | Create a file. |
| `#edit/editFiles` | Apply edits to files. |
| `#edit/editNotebook` | Edit a notebook. |
| `#read/getNotebookSummary` | List notebook cells and their details. |
| `#read/readNotebookCellOutput` | Read the output from a notebook cell. |
| `#execute/runNotebookCell` | Run a notebook cell. |

### Run commands and diagnose tests

| Reference | Purpose |
|---|---|
| `#execute/createAndRunTask` | Create and run a [workspace task](/docs/debugtest/tasks.md). |
| `#execute/getTerminalOutput` | Get output from a running terminal command. |
| `#execute/runInTerminal` | Run a shell command in the integrated terminal. |
| `#execute/testFailure` | Get unit test failure information. |
| `#read/terminalLastCommand` | Get the last terminal command and its output. |
| `#read/terminalSelection` | Get the current terminal selection. |

### Access the web and GitHub

| Reference | Purpose |
|---|---|
| `#web/fetch` | Fetch a web page. |
| `#githubRepo` | Search a GitHub repository semantically. Specify the repository as `owner/repo`. |
| `#githubTextSearch` | Search a GitHub repository or organization for text or code patterns. |

### Delegate and track work

| Reference | Purpose |
|---|---|
| `#agent/runSubagent` | Run a task in an isolated subagent context. |
| `#todos` | Track task progress with a todo list. |
| `#vscode/askQuestions` | Ask clarifying questions with interactive controls. |

To coordinate work across sessions, see [Coordinate work across sessions](/docs/agents/run/tools.md#coordinate-work-across-sessions).

### Configure projects and the editor

| Reference | Purpose |
|---|---|
| `#newWorkspace` | Create a workspace. |
| `#vscode/extensions` | Search for extensions and information about them. |
| `#vscode/getProjectSetupInfo` | Get project-scaffolding instructions and configuration. |
| `#vscode/installExtension` | Install an extension. |
| `#vscode/runCommand` | Run a VS Code command. |
| `#vscode/VSCodeAPI` | Get information about editor functionality and extension APIs. |

## Context items

Type `#` followed by a file, folder, or symbol name, then select the item from the picker. The placeholders below represent the name of the item you want to attach.

| Reference | Context supplied |
|---|---|
| `#<file>` | A file selected from the context picker. |
| `#<folder>` | A folder selected from the context picker. |
| `#<symbol>` | A code symbol. Open the file containing the symbol first. |
| `#selection` | The current editor selection, available when text is selected. |

Use **Add Context** or drag items into chat to attach other context, such as images, errors, or GitHub issues. See [Add context to chat](/docs/chat/copilot-chat-context.md) for supported sources and attachment methods.

## Related resources

* [Understand tools in the agent loop](/docs/agents/concepts/tools.md).
* [Migrate existing customizations](/docs/agent-customization/migrate-customizations.md).