BTerminal/.claude/CLAUDE.md

BTerminal — Claude Behavioral Guide

Workflow

• v1 is a single-file Python app (bterminal.py). Changes are localized.
• v2 docs are in docs/. Architecture decisions are in docs/task_plan.md.
• Phases 1-7 + multi-machine (A-D) complete. Extras: SSH, ctx, themes, detached mode, auto-updater, shiki, copy/paste, session resume, drag-resize, session groups, Deno sidecar, 114 vitest + 29 cargo tests.
• Consult Memora (tag: bterminal) before making architectural changes.

Documentation References

• Architecture & decisions: docs/task_plan.md
• Implementation phases: docs/phases.md
• Research findings: docs/findings.md
• Progress log: docs/progress.md

Rules

• Do not modify v1 code (bterminal.py) unless explicitly asked — it is production-stable.
• v2 work goes on a feature branch (v2-mission-control), not master.
• All v2 architecture decisions must reference docs/task_plan.md Decisions Log.
• When adding new decisions, append to the Decisions Log table with date.
• Update docs/progress.md after each significant work session.

Key Technical Constraints

• WebKit2GTK has no WebGL — xterm.js must use Canvas addon explicitly.
• Agent sessions use @anthropic-ai/claude-agent-sdk query() function (migrated from raw CLI spawning due to piped stdio hang bug). SDK handles subprocess management internally. All output goes through the adapter layer (src/lib/adapters/sdk-messages.ts) — SDK message format matches CLI stream-json.
• Sidecar uses a single pre-built bundle (sidecar/dist/agent-runner.mjs) that runs on both Deno and Node.js. SidecarCommand struct in sidecar.rs abstracts runtime (Deno preferred for faster startup, Node.js fallback). Communicates with Rust via stdio NDJSON. Claude CLI auto-detected at startup via findClaudeCli() — checks ~/.local/bin/claude, ~/.claude/local/claude, /usr/local/bin/claude, /usr/bin/claude, then which claude. Path passed to SDK via pathToClaudeCodeExecutable option. Agents error immediately if CLI not found. CLAUDE* env var stripping is dual-layer: (1) Rust SidecarManager uses env_clear() + envs(clean_env) to strip all CLAUDE* vars before spawning the sidecar process, (2) JS runner also strips via SDK's env option (defense-in-depth). Without this, nesting detection triggers when BTerminal is launched from a Claude Code terminal. Session stop uses AbortController.abort() (not process.kill()). agent-runner-deno.ts exists as standalone alternative runner but is NOT used by SidecarManager.
• AgentPane does NOT stop agents in onDestroy — onDestroy fires on layout remounts, not just explicit close. Stop-on-close is handled by TilingGrid.svelte's onClose handler (checks pane type + session status before calling stopAgent).
• Agent dispatcher (src/lib/agent-dispatcher.ts) is a singleton that routes sidecar events to the agent store. Also handles subagent pane spawning (SUBAGENT_TOOL_NAMES detection, toolUseToChildPane routing map).
• AgentQueryOptions supports permission_mode field (flows Rust -> sidecar -> SDK). Defaults to 'bypassPermissions', supports 'default' mode. allowDangerouslySkipPermissions is conditionally set.
• Sidecar build: npm run build:sidecar bundles SDK into agent-runner.mjs via esbuild (no --external, SDK included in bundle).
• Maximum 4 active xterm.js instances to avoid WebKit2GTK memory issues.
• Store files using Svelte 5 runes ($state, $derived) MUST have .svelte.ts extension (not .ts). Import with .svelte suffix. Plain .ts compiles but fails at runtime with "rune_outside_svelte".
• Session persistence uses rusqlite (bundled) with WAL mode. Data dir: dirs::data_dir()/bterminal/sessions.db.
• Layout store persists to SQLite on every addPane/removePane/setPreset/setPaneGroup change (fire-and-forget). Restores on app startup via restoreFromDb().
• Session groups: Pane.group? field in layout store, group_name column in sessions table, collapsible group headers in sidebar. Right-click pane to set group.
• File watcher uses notify crate v6, watches parent directory (NonRecursive), emits file-changed Tauri events.
• Settings use key-value settings table in SQLite (session.rs). Frontend: settings-bridge.ts adapter, SettingsDialog.svelte component.
• Notifications use ephemeral toast system: notifications.svelte.ts store (max 5, 4s auto-dismiss), ToastContainer.svelte display. Agent dispatcher emits toasts on agent complete/error/crash.
• StatusBar component spans full grid width (grid-column: 1 / -1), shows pane counts, active agents, tokens, cost.
• Agent tree (AgentTree.svelte) uses SVG with recursive layout. Tree data built by agent-tree.ts utility from agent messages.
• ctx integration opens ~/.claude-context/context.db as SQLITE_OPEN_READ_ONLY — never writes. CtxDb uses Option for graceful absence if DB doesn't exist.
• SSH sessions spawn TerminalPane with shell=/usr/bin/ssh and args array. No SSH library needed — PTY handles it natively.
• Theme flavors (Latte/Frappe/Macchiato/Mocha) override CSS variables at runtime. Open terminals hot-swap via onThemeChange() callback registry in theme.svelte.ts.
• Detached pane mode: App.svelte checks URL param ?detached=1 and renders a single pane without sidebar/grid chrome. Used for pop-out windows.
• Shiki syntax highlighting uses lazy singleton pattern (avoid repeated WASM init). 13 languages preloaded. Used in MarkdownPane and AgentPane text messages.
• Cargo workspace at v2/ level: members = [src-tauri, bterminal-core, bterminal-relay]. Cargo.lock is at workspace root (v2/), not in src-tauri/.
• EventSink trait (bterminal-core/src/event.rs) abstracts event emission. PtyManager and SidecarManager are in bterminal-core, not src-tauri. src-tauri has thin re-exports.
• RemoteManager (src-tauri/src/remote.rs) manages WebSocket client connections to bterminal-relay instances. 12 Tauri commands prefixed with remote_.
• remote-bridge.ts adapter wraps remote machine management IPC. machines.svelte.ts store tracks remote machine state.
• Pane.remoteMachineId?: string routes operations through RemoteManager instead of local managers. Bridge adapters (pty-bridge, agent-bridge) check this field.
• bterminal-relay binary (v2/bterminal-relay/) is a standalone WebSocket server with token auth, rate limiting, and per-connection isolated managers. Commands return structured responses (pty_created, pong, error) with commandId for correlation via send_error() helper.
• RemoteManager reconnection: exponential backoff (1s-30s cap) on disconnect, attempt_tcp_probe() (TCP-only, no WS upgrade), emits remote-machine-reconnecting and remote-machine-reconnect-ready events. Frontend listeners in remote-bridge.ts; machines store auto-reconnects on ready.

Memora Tags

Project tag: bterminal Common tag combinations: bterminal,architecture, bterminal,research, bterminal,tech-stack

Operational Rules

All operational rules live in .claude/rules/. Every .md file in that directory is automatically loaded at session start by Claude Code with the same priority as this file.

Rule Index

#	File	Scope
01	security.md	PARAMOUNT — secrets, input validation, least privilege
02	error-handling.md	PARAMOUNT — handle every error visibly
03	environment-safety.md	PARAMOUNT — verify target, data safety, K8s isolation, cleanup
04	communication.md	Stop on ambiguity, scope discipline
05	git-practices.md	Conventional commits, authorship
06	testing.md	TDD, unit tests, E2E tests
07	documentation.md	README, CLAUDE.md sync, docs/
08	branch-hygiene.md	Branches, naming, clean state before refactors
09	dependency-discipline.md	No deps without consent
10	code-consistency.md	Match existing patterns
11	api-contracts.md	Contract-first, flag breaking changes (path-conditional)
12	performance-awareness.md	No N+1, no unbounded fetches (path-conditional)
13	logging-observability.md	Structured logging, OTEL (path-conditional)
14	resilience-and-config.md	Timeouts, circuit breakers, externalized config (path-conditional)
15	memora.md	Persistent memory across sessions
16	sub-agents.md	When to use sub-agents and team agents
17	document-imports.md	Resolve @ imports in CLAUDE.md before acting