# Using DM

This page collects day-to-day usage details that do not fit on the quickstart page.

## Interactive Mode

<p align="center"><img src="images/interactive-mode.png" alt="Interactive Mode" width="600"></p>

The interface has four main areas:

- **Startup header** - shortcuts, loaded context files, prompt templates, skills, and extensions
- **Messages** - user messages, assistant responses, tool calls, tool results, notifications, errors, and extension UI
- **Editor** - where you type; border color indicates the current thinking level
- **Footer** - working directory, session name, token/cache usage, cost, context usage, and current model

The editor can be replaced temporarily by built-in UI such as `/settings` or by custom extension UI.

### Editor Features

| Feature | How |
|---------|-----|
| File reference | Type `@` to fuzzy-search project files |
| Path completion | Press Tab to complete paths |
| Multi-line input | Shift+Enter, or Ctrl+Enter on Windows Terminal |
| Images | Paste with Ctrl+V, Alt+V on Windows, or drag into the terminal |
| Shell command | `!command` runs and sends output to the model |
| Hidden shell command | `!!command` runs without sending output to the model |
| External editor | Ctrl+G opens `$VISUAL` or `$EDITOR` |

See [Keybindings](keybindings.md) for all shortcuts and customization.

## Slash Commands

Type `/` in the editor to open command completion. Extensions can register custom commands, skills are available as `/skill:name`, and prompt templates expand via `/templatename`.

| Command | Description |
|---------|-------------|
| `/login`, `/logout` | Manage OAuth or API-key credentials |
| `/model` | Switch models |
| `/settings` | Thinking level, theme, message delivery, transport |
| `/resume` | Pick from previous sessions |
| `/new` | Start a new session |
| `/name <name>` | Set session display name |
| `/session` | Show session file, ID, messages, tokens, and cost |
| `/tree` | Jump to any point in the session and continue from there |
| `/fork` | Create a new session from a previous user message |
| `/clone` | Duplicate the current active branch into a new session |
| `/compact [prompt]` | Manually compact context, optionally with custom instructions |
| `/copy` | Copy last assistant message to clipboard |
| `/export [file]` | Export session to HTML |
| `/share` | Upload as private GitHub gist with shareable HTML link |
| `/reload` | Reload keybindings, extensions, skills, prompts, and context files |
| `/hotkeys` | Show all keyboard shortcuts |
| `/quit` | Quit dm |

## Message Queue

You can submit messages while the agent is still working:

- **Enter** queues a steering message, delivered after the current assistant turn finishes executing its tool calls.
- **Alt+Enter** queues a follow-up message, delivered after the agent finishes all work.
- **Escape** aborts and restores queued messages to the editor.
- **Alt+Up** retrieves queued messages back to the editor.

On Windows Terminal, Alt+Enter is fullscreen by default. Remap it as described in [Terminal setup](terminal-setup.md) if you want dm to receive the shortcut.

Configure delivery in [Settings](settings.md) with `steeringMode` and `followUpMode`.

## Sessions

Sessions are saved automatically to `~/.dm/agent/sessions/`, organized by working directory.

```bash
dm -c                  # Continue most recent session
dm -r                  # Browse and select a session
dm --no-session        # Ephemeral mode; do not save
dm --session <path|id> # Use a specific session file or session ID
dm --fork <path|id>    # Fork a session into a new session file
```

Useful session commands:

- `/session` shows the current session file and ID.
- `/tree` navigates the in-file session tree and can summarize abandoned branches.
- `/fork` creates a new session from an earlier user message.
- `/clone` duplicates the current active branch into a new session file.
- `/compact` summarizes older messages to free context.

See [Sessions](sessions.md) and [Compaction](compaction.md) for details.

## Context Files

DM loads `AGENTS.md` or `CLAUDE.md` at startup from:

- `~/.dm/agent/AGENTS.md` for global instructions
- parent directories, walking up from the current working directory
- the current directory

Use context files for project conventions, commands, safety rules, and preferences. Disable loading with `--no-context-files` or `-nc`.

### System Prompt Files

Replace the default system prompt with:

- `.dm/SYSTEM.md` for a project
- `~/.dm/agent/SYSTEM.md` globally

Append to the default prompt without replacing it with `APPEND_SYSTEM.md` in either location.

## Exporting and Sharing Sessions

Use `/export [file]` to write a session to HTML.

Use `/share` to upload a private GitHub gist with a shareable HTML link.

If you use dm for open source work and want to publish sessions for model, prompt, tool, and evaluation research, see the DuckMind session publisher. It publishes sessions to Hugging Face datasets.

## CLI Reference

```bash
dm [options] [@files...] [messages...]
```

### Package Commands

```bash
dm install <source> [-l]     # Install package, -l for project-local
dm remove <source> [-l]      # Remove package
dm uninstall <source> [-l]   # Alias for remove
dm update [source|self|dm]   # Update dm and packages; reconcile pinned git refs
dm update --extensions       # Update packages only; reconcile pinned git refs
dm update --self             # Update dm only
dm update --extension <src>  # Update one package
dm list                      # List installed packages
dm config                    # Enable/disable package resources
```

These commands manage dm packages, not the dm CLI installation. To uninstall dm itself, see [Quickstart](quickstart.md#uninstall).

See [DM Packages](packages.md) for package sources and security notes.

### Modes

| Flag | Description |
|------|-------------|
| default | Interactive mode |
| `-p`, `--print` | Print response and exit |
| `--mode json` | Output all events as JSON lines; see [JSON mode](json.md) |
| `--mode rpc` | RPC mode over stdin/stdout; see [RPC mode](rpc.md) |
| `--export <in> [out]` | Export a session to HTML |

In print mode, dm also reads piped stdin and merges it into the initial prompt:

```bash
cat README.md | dm -p "Summarize this text"
```

### Model Options

| Option | Description |
|--------|-------------|
| `--provider <name>` | Provider, such as `anthropic`, `openai`, or `google` |
| `--model <pattern>` | Model pattern or ID; supports `provider/id` and optional `:<thinking>` |
| `--api-key <key>` | API key, overriding environment variables |
| `--thinking <level>` | `off`, `minimal`, `low`, `medium`, `high`, `xhigh` |
| `--models <patterns>` | Comma-separated patterns for Ctrl+P cycling |
| `--list-models [search]` | List available models |

### Session Options

| Option | Description |
|--------|-------------|
| `-c`, `--continue` | Continue the most recent session |
| `-r`, `--resume` | Browse and select a session |
| `--session <path\|id>` | Use a specific session file or partial UUID |
| `--fork <path\|id>` | Fork a session file or partial UUID into a new session |
| `--session-dir <dir>` | Custom session storage directory |
| `--no-session` | Ephemeral mode; do not save |

### Tool Options

| Option | Description |
|--------|-------------|
| `--tools <list>`, `-t <list>` | Allowlist specific built-in, extension, and custom tools |
| `--no-builtin-tools`, `-nbt` | Disable built-in tools but keep extension/custom tools enabled |
| `--no-tools`, `-nt` | Disable all tools |

Built-in tools: `read`, `bash`, `edit`, `write`, `grep`, `find`, `ls`.

### Resource Options

| Option | Description |
|--------|-------------|
| `-e`, `--extension <source>` | Load an extension from path, npm, or git; repeatable |
| `--no-extensions` | Disable extension discovery |
| `--skill <path>` | Load a skill; repeatable |
| `--no-skills` | Disable skill discovery |
| `--prompt-template <path>` | Load a prompt template; repeatable |
| `--no-prompt-templates` | Disable prompt template discovery |
| `--theme <path>` | Load a theme; repeatable |
| `--no-themes` | Disable theme discovery |
| `--no-context-files`, `-nc` | Disable `AGENTS.md` and `CLAUDE.md` discovery |

Combine `--no-*` with explicit flags to load exactly what you need, ignoring settings. Example:

```bash
dm --no-extensions -e ./my-extension.ts
```

### Other Options

| Option | Description |
|--------|-------------|
| `--system-prompt <text>` | Replace default prompt; context files and skills are still appended |
| `--append-system-prompt <text>` | Append to system prompt |
| `--verbose` | Force verbose startup |
| `-h`, `--help` | Show help |
| `-v`, `--version` | Show version |

### File Arguments

Prefix files with `@` to include them in the message:

```bash
dm @prompt.md "Answer this"
dm -p @screenshot.png "What's in this image?"
dm @code.ts @test.ts "Review these files"
```

### Examples

```bash
# Interactive with initial prompt
dm "List all .ts files in src/"

# Non-interactive
dm -p "Summarize this codebase"

# Non-interactive with piped stdin
cat README.md | dm -p "Summarize this text"

# Different model
dm --provider openai --model gpt-4o "Help me refactor"

# Model with provider prefix
dm --model openai/gpt-4o "Help me refactor"

# Model with thinking level shorthand
dm --model sonnet:high "Solve this complex problem"

# Limit model cycling
dm --models "claude-*,gpt-4o"

# Read-only mode
dm --tools read,grep,find,ls -p "Review the code"
```

### Environment Variables

| Variable | Description |
|----------|-------------|
| `PI_CODING_AGENT_DIR` | Override config directory; default is `~/.dm/agent` |
| `PI_CODING_AGENT_SESSION_DIR` | Override session storage directory; overridden by `--session-dir` |
| `PI_PACKAGE_DIR` | Override package directory, useful for Nix/Guix store paths |
| `PI_OFFLINE` | Disable startup network operations, including update checks, package update checks, and install/update telemetry |
| `PI_SKIP_VERSION_CHECK` | Skip the DM version update check at startup. This prevents the DuckMind latest-version request |
| `PI_TELEMETRY` | Override install/update telemetry: `1`/`true`/`yes` or `0`/`false`/`no`. This does not disable update checks |
| `PI_CACHE_RETENTION` | Set to `long` for extended prompt cache where supported |
| `VISUAL`, `EDITOR` | External editor for Ctrl+G |

## Design Principles

DM keeps the core small and pushes workflow-specific behavior into extensions, skills, prompt templates, and packages.

It intentionally does not include built-in MCP, sub-agents, permission popups, plan mode, to-dos, or background bash. You can build or install those workflows as extensions or packages, or use external tools such as containers and tmux.

For the full rationale, read the [blog post](https://mariozechner.at/posts/2025-11-30-pi-coding-agent/).
