Bcode

Bcode is a Rust-native, TUI-first, plugin-driven coding agent with a local client/server architecture.

TUI keybindings

TUI keybindings are configurable in bcode.toml under scoped [tui.keybindings.*] tables. Each scope maps key = "action.id", matching bmux-style key-to-action configuration. Set a key to "", "none", or "unbind" to remove a default binding for that key.

[tui.keybindings.chat]
"enter" = "tui.input.submitSteering"
"ctrl+shift+enter" = "tui.input.submitFollowUp"
"shift+enter" = "tui.input.newLine"
"up" = "tui.input.historyPrevious"
"down" = "tui.input.historyNext"
"left" = "tui.editor.moveCursorLeft"
"right" = "tui.editor.moveCursorRight"
"alt+left" = "tui.editor.moveCursorWordLeft"
"alt+right" = "tui.editor.moveCursorWordRight"
"ctrl+left" = "tui.editor.moveCursorWordLeft"
"ctrl+right" = "tui.editor.moveCursorWordRight"
"ctrl+a" = "tui.editor.moveCursorStart"
"ctrl+e" = "tui.editor.moveCursorEnd"
"backspace" = "tui.editor.deleteCharBackward"
"delete" = "tui.editor.deleteCharForward"
"alt+backspace" = "tui.editor.deleteWordBackward"
"ctrl+w" = "tui.editor.deleteWordBackward"
"alt+delete" = "tui.editor.deleteWordForward"
"ctrl+delete" = "tui.editor.deleteWordForward"
"ctrl+u" = "tui.editor.deleteToStart"
"ctrl+k" = "tui.editor.deleteToEnd"
"escape" = "app.interrupt"
"ctrl+d" = "app.exit"
"ctrl+c" = "app.clear"
"ctrl+f" = "app.search"
"pageUp" = "transcript.pageUp"
"pageDown" = "transcript.pageDown"

[tui.keybindings.permission]
"y" = "app.permission.approve"
"n" = "app.permission.deny"
"a" = "app.permission.alwaysAllow"
"d" = "app.permission.alwaysDeny"
"left" = "tui.select.previous"
"right" = "tui.select.next"
"enter" = "tui.select.confirm"
"escape" = "tui.select.cancel"

[tui.keybindings.session_picker]
"up" = "tui.select.previous"
"down" = "tui.select.next"
"enter" = "tui.select.confirm"
"escape" = "tui.select.cancel"

Key format follows modifier+key, with ctrl, alt, and shift modifiers. Examples: ctrl+d, alt+left, pageUp, escape, enter.

The chat composer uses a Unicode-aware editor buffer. Standard composer defaults include up / down session message history navigation, left/right grapheme movement, alt+left / alt+right and ctrl+left / ctrl+right word movement, ctrl+a / ctrl+e start/end movement, backspace / delete character deletion, alt+backspace / ctrl+w word-backward deletion, alt+delete / ctrl+delete word-forward deletion, and ctrl+u / ctrl+k delete-to-start/end. Plain home and end remain transcript top/bottom bindings in the chat scope by default.

Permission prompts are modal by default: permission actions only apply in the permission scope, and hints are generated from the configured permission keymap.

Permissions

Bcode uses an agent-scoped permission model with allow / ask / deny rules under [agent.<id>.permission] in bcode.toml. See docs/permissions.md for the full shape, category list, and built-in defaults for the plan and build agents.

Plugin and tool selection

Bcode separates plugin loading from model-callable tool exposure. Statically bundled plugins are compiled into the Bcode binary, but users can still opt out of bundled defaults or opt in to individual plugins.

[plugins]
default = "none"
enabled = ["bcode.default-agents", "bcode.filesystem", "bcode.vim-edit"]

[tools]
default = "none"
enabled = ["filesystem.read", "vim_edit.preview"]

Use default = "bundled" under [plugins] to enable Bcode's bundled defaults unless disabled, default = "none" to start with no default plugins, or default = "all" to enable every discovered plugin unless disabled. Under [tools], default = "agent" uses the active agent's normal tool policy, default = "none" exposes only explicitly enabled tools, and default = "all" exposes all loaded tools except those in disabled.

[plugins]
disabled = ["bcode.vim-edit"]

[tools]
disabled = ["vim_edit.apply"]

Auth vault device seals

Bcode stores provider secrets in sshenv-backed auth vault profiles. By default, Bcode prefers a strict transparent device-only seal for those profiles: macOS uses a non-syncing ThisDeviceOnly Keychain item, Windows uses current-user DPAPI, and Linux uses TPM when available. If the seal cannot be applied and device_seal = "preferred", Bcode continues with a warning; device_seal = "required" turns that into an error.

Advanced auth profile settings can override the default:

[auth.profiles.openai.settings]
device_seal = "preferred"              # off, preferred, required
device_seal_mode = "transparent-device-only" # transparent-device-only, default
device_seal_strict = "true"
# Optional explicit backend override:
# device_seal_backend = "macos-keychain-device-only"

Run bcode auth status to inspect the configured mode and the backend recorded in vault metadata.

Session import

Bcode can discover sessions from other coding agents through bundled session-import plugins. The Pi importer is enabled by default and reads Pi JSONL history without mutating Pi's files.

In the TUI, open the session picker or run /rescan-imports; importable rows are marked like [pi import]. Selecting one copies it into a normal Bcode session and continuation uses Bcode's selected provider, agent, tools, and permissions. Imported external tool calls are inert history and are not replayed.

CLI helpers:

bcode session import sources
bcode session import discover --source pi
bcode session import discover --source pi --diagnostics
bcode session import open --source pi <external-session-id>

Configuration lives under [session_import] and [session_import.pi]:

[session_import]
enabled = true
hide_already_imported = true

[session_import.pi]
enabled = true
path_mode = "defaults_and_custom" # defaults_only, custom_only, defaults_and_custom
paths = ["/path/to/pi/sessions"]

The default Pi path is ~/.pi/agent/sessions. Use custom_only to avoid scanning the default home-directory location. Import warnings are shown when mappings are lossy, such as image blocks that are not yet copied into Bcode artifacts.