Interactive Mode

nca provides a rich interactive experience with a full-screen TUI (Terminal User Interface) and a fallback line-oriented REPL.

TUI vs REPL

Mode	When Used	Features
TUI (default)	Terminal is a TTY, `--stream human`, no `--no-tui`	Full-screen, scrollable output, command palette, modals, mouse support
Line REPL	`--no-tui` flag, or non-TTY stdin/stdout	Simple line-by-line input/output, still supports slash commands

Force line REPL mode:

nca --no-tui

Live Busy Activity

While the agent is working, the TUI keeps progress visible so long model waits do not look stuck:

Busy state	What you see
thinking	Animated spinner + elapsed seconds (`thinking 12s`) and a transcript footer like `waiting for model · 12s`
streaming	Stream progress with character count
tool	Tool name plus a one-liner (file path for `write_file` / `edit_file`, command for `execute_bash`)
approval	Waiting for y/n or Ctrl+Y / Ctrl+N / Ctrl+U

Empty provider responses that are still retrying stay in thinking (soft retry), instead of flipping the status bar to a hard error mid-turn. The sidebar status field mirrors the same busy label.

Input Modes

Regular Text

Type your message and press Enter to send it to the agent.

Shell Commands (`!`)

Prefix with ! to run a shell command directly. The output is captured and fed into the conversation context.

! cargo test
! git log --oneline -5
! ls -la src/

File Mentions (`@`)

Type @ followed by a path to inline-reference a file. nca performs fuzzy file search and auto-completion.

Can you review @src/main.rs and @src/lib.rs?

In the TUI, pressing @ opens a file picker with fuzzy search. Use Tab to navigate matches and Enter to select.

Multiline Input (`\`)

End a line with \ to continue input on the next line:

Write a function that \
takes a vector of strings \
and returns the longest one.

Slash Commands (`/`)

Type / to access slash commands. In the TUI, this opens an inline autocomplete menu.

Slash Commands

General

Command	Description
`/help`	Show help with all commands and keyboard shortcuts
`/status`	Display session status (ID, model, agent profile, permission mode)
`/clear`	Clear the screen
`/exit`, `/quit`, `/q`	Exit the session
`/new`	Start a new session
`/export`	Export the current session to markdown
`/stop`	Cancel the current agent turn

Agent Profiles

Command	Description
`/agent [profile]`	Show or switch agent profile
`/plan <task>`	Run a planning-oriented turn (read-only analysis)
`/review <task>`	Run a code review turn
`/fix <task>`	Run a bug-fix turn
`/test <task>`	Run a validation/testing turn

Available agent profiles:

Profile	Description
`@build`	Default full-access agent for development work
`@plan`	Read-only agent for analysis and planning
`@review`	Focused code review agent
`@fix`	Bug diagnosis and fix agent
`@test`	Testing and validation agent

Model and Provider

Command	Description
`/models`	Browse and select models (opens picker in TUI)
`/model [name]`	Set the active model for the session
`/connect`	Open the provider connection picker
`/provider [name]`	Show or set the default LLM provider
`/custom <compat> <url> [key] [model]`	Configure a custom endpoint (OpenAI or Anthropic compatible)
`/apikey <provider> <key>`	Store an API key for a provider

Session and Context

Command	Description
`/compact`	Compact session context (summarize and trim history)
`/copy`	Copy the latest assistant response to the clipboard (TUI)
`/todos`	Show the session todo list (sidebar also shows a compact view)
`/thinking`	Toggle thinking/reasoning visibility
`/sessions`	List and switch between sessions
`/agents`	List child sub-agent sessions
`/logs`	View session event log
`/attach`	Attach to a session
`/diff`	Show recent file changes
`/cost`	Show token usage and costs
`/stats`	Show session statistics

Tools and Configuration

Command	Description
`/skills`	List discovered skills
`/memory [text]`	Show memory notes, or add a note
`/mcp`	List MCP servers
`/permissions [mode]`	Show or set permission mode
`/permission-bypass`	Toggle permission bypass
`/config`	Show runtime configuration
`/doctor`	Run configuration diagnostics
`/settings`	Show settings

Editor

Command	Description
`/editor [seed]`	Open an external editor to compose a message
`/set-editor <cmd>`	Persist the editor command (e.g., `vim`, `code --wait`)

Images

Command	Description
`/image`	Manage staged image attachments

Other

Command	Description
`/undo`	Undo last file change
`/redo`	Redo last undone change
`/auto-answer`	Auto-answer agent questions with suggested answer

Keyboard Shortcuts

Shortcut	Action
`Enter`	Send message
`Esc`	Cancel current agent turn / close modal
`Ctrl+C`	Cancel request
`Ctrl+L`	Clear screen
`Ctrl+Q`	Exit
`Mouse wheel`	Scroll output
`End`	Jump to bottom of transcript (on empty input)

Agent and Model

Shortcut	Action
`Tab`	Cycle agent profile (build → plan → review → fix → test)
`F2`	Cycle through recent models (forward)
`Shift+F2`	Cycle through recent models (backward)

Command Palette and Pickers

Shortcut	Action
`Ctrl+P`	Open command palette
`Ctrl+V`	Paste image from clipboard (TUI only)
`Ctrl+Shift+C`	Copy last assistant response (TUI only)
`Ctrl+X M`	Switch model (model picker)
`Ctrl+X E`	Open external editor
`Ctrl+X L`	Switch session
`Ctrl+X N`	New session
`Ctrl+X C`	Compact context
`Ctrl+X S`	View status
`Ctrl+X A`	Agent profile picker
`Ctrl+X H`	Show help
`Ctrl+X Q`	Exit

Within Modals and Pickers

Shortcut	Action
`↑` / `↓`	Navigate options
`Enter`	Select / confirm
`Esc`	Close modal
`j` / `k`	Navigate (in info modals)

Agent Question Modals

When the agent asks a structured question:

Shortcut	Action
`↑` / `↓`	Select an option
`Enter`	Confirm selection (or accept suggested answer on empty input)
`0`	Accept suggested answer
`1`–`n`	Select option by number
`c`	Type a custom answer

Command Palette

Press Ctrl+P to open the command palette — a searchable list of all available commands. Type to filter, use ↑/↓ to navigate, and Enter to execute.

Status Bar

The TUI displays a status bar at the bottom showing:

Current agent profile
Active model
Available shortcuts hint

Tab  agent   Ctrl+V  image   Ctrl+Shift+C  copy   Ctrl+P  commands   !cmd  shell   @path  search   /  inline   wheel  scroll

Copying Text

Mouse drag-selection is limited while the TUI owns the terminal. Use:

/copy or Ctrl+Shift+C to copy the latest assistant response
Native terminal Shift+drag selection as a fallback when you need arbitrary transcript text

Session Todos

The agent maintains a session checklist through the update_todos tool (full-list replacement). The TUI sidebar shows a compact progress view; /todos opens the full list (useful on narrow terminals). Todos persist in session JSON and replay via TodosUpdated events.

Image Attachments

In the TUI, paste images from your clipboard with Ctrl+V or use the /image command. Images are processed through MiniMax native vision and the text description is injected into the conversation.

Vi Mode

If your NCA_EDITOR_MODE environment variable is set to vi or vim, the REPL uses vi keybindings for line editing.

export NCA_EDITOR_MODE=vi

External Editor

For composing long messages, use /editor to open your configured external editor. The content is sent as your message when you save and close.

Editor resolution order:

NCA_EDITOR environment variable
[ui].editor in config
EDITOR environment variable
vim (fallback)