ForkTTY

Linux-native multi-agent terminal with a programmable local socket API, first-class git worktrees, and prompt-aware notifications.

ForkTTY runs coding agents in isolated workspaces, exposes a user-local Unix socket for automation, and can place long-running tasks in dedicated git worktrees without tying the UI to one agent vendor.

Website · Docs · Agent context · Download v0.2.0-alpha.16 AppImage

Status: Early alpha (v0.2.0-alpha.16). ForkTTY is Linux-only and the GTK/Ghostty runtime is now the primary implementation. The AppImage is the primary Linux download for this alpha; the Debian package remains available for Debian/Ubuntu users.

For the complete user guide, read forktty.dev/docs. For agent-oriented retrieval, start with llms.txt or the single-file llms-full.txt. This README stays focused on the project overview, install paths, quick start, and contributor commands.

Why ForkTTY

• Agent-agnostic automation: the same socket API and CLI flow work for Codex, Claude Code, Pi, Antigravity CLI, OpenCode, shell scripts, and custom tools.
• First-class worktree workflows: create, attach, remove, and merge isolated worktree workspaces through native git2 operations and optional .forktty/setup / .forktty/teardown hooks.
• Native Linux terminal stack: GTK4/libadwaita shell with embedded Ghostty-backed terminals, split panes, session restore, notifications, command palette, settings, and quake mode.
• Local-first posture: no crash reporting or product event tracking, an anonymous daily usage ping that can be disabled, owner-only Unix socket permissions, bounded request/session/config files, and argv-based command execution. Optional update checks hit GitHub Releases at most once per day and can also be disabled.

Install

The fastest paths are the prebuilt artifacts from the v0.2.0-alpha.16 release. Each release ships:

• forktty-0.2.0-alpha.16-x86_64.AppImage — recommended portable Linux package.
• forktty-0.2.0-alpha.16-x86_64.AppImage.zsync — AppImage delta-update metadata for external AppImage managers.
• forktty_0.2.0.alpha.16_amd64.deb — Debian/Ubuntu package.
• SHA256SUMS — checksums for release artifacts.

After downloading, verify checksums:

sha256sum -c SHA256SUMS

AppImage

chmod +x forktty-0.2.0-alpha.16-x86_64.AppImage
./forktty-0.2.0-alpha.16-x86_64.AppImage

The AppImage always ships the vendored libghostty-vt library and prefers the host's GUI stack: when the host provides GTK4, ForkTTY runs against the system GTK4/libadwaita for native cursor themes, fontconfig, and portal integration, and the bundled GTK copy is used only as a fallback on hosts without GTK4. Set FORKTTY_APPIMAGE_GTK_RUNTIME=bundled, host, or auto to force or debug that runtime choice. It depends on the host system for glibc, the GSettings/GIO data tree, Wayland/X11 session services, fontconfig, the OpenGL/Vulkan/Mesa driver stack, and desktop notification services. It is the primary downloadable artifact for alpha releases and works on most modern distros that ship a recent glibc, but it should still be tested on the target distro/desktop environment before being relied on.

ForkTTY checks GitHub Releases for updates at most once per day by default. AppImage installs can update in place after confirmation: ForkTTY downloads the new AppImage and SHA256SUMS, verifies SHA256, then atomically replaces the current file. Non-AppImage installs open the release page instead. AppImage managers such as Gear Lever continue to work when they launch ForkTTY from a stable writable AppImage path; if ForkTTY sees an extracted, read-only, or otherwise unsafe path, it falls back to the release page and leaves the manager in control.

ForkTTY defaults to the OpenGL GTK renderer (GSK_RENDERER=ngl). If the AppImage launches but the GTK interface renders incorrectly, override it with a different renderer from a terminal:

GSK_RENDERER=gl ./forktty-0.2.0-alpha.16-x86_64.AppImage

Use GSK_RENDERER=cairo only as a last resort: the software renderer is slower and retains far more memory under heavy terminal redraws.

Debian / Ubuntu (.deb)

The .deb targets Debian 13/Trixie or newer and Ubuntu 24.04 LTS or newer. Debian 12/Bookworm is below the package baseline because it does not provide libadwaita 1.4+.

sudo apt install ./forktty_0.2.0.alpha.16_amd64.deb
# or, if apt cannot read the file path directly:
sudo dpkg -i forktty_0.2.0.alpha.16_amd64.deb
sudo apt -f install

The package installs the forktty binary, the desktop entry, and the icon. Removing it (sudo apt remove forktty) cleans up /usr/bin/forktty and the desktop integration.

Build from source

Requirements:

• Linux
• Rust 1.96+
• GTK4 and libadwaita development files
• git, Zig, and the full Ghostty source submodule for the vendored Ghostty terminal libraries
• No system Ghostty package is required; source and packaged builds use the pinned vendored Ghostty libraries

Developer repository checks also expect the full Ghostty source submodule:

git submodule update --init vendor/ghostty

Debian / Ubuntu:

sudo apt install build-essential libssl-dev libgtk-4-dev libadwaita-1-dev git zig desktop-file-utils

Fedora:

sudo dnf install gcc gcc-c++ openssl-devel gtk4-devel libadwaita-devel git zig desktop-file-utils

Arch / CachyOS:

sudo pacman -S base-devel openssl gtk4 libadwaita git zig desktop-file-utils

Source builds require libadwaita 1.4+, matching Debian 13/Trixie, Ubuntu 24.04 LTS, and newer distro packages. Release AppImages bundle GTK4, libadwaita, and gtk4-layer-shell so terminal panes do not depend on those host packages.

Clone and run:

git clone https://github.com/Lucenx9/forktty.git
cd forktty
git submodule update --init vendor/ghostty
scripts/ghostty-gtk-lib-probe.sh --ensure --print-path
cargo run -p forktty-ui-gtk

Packaged builds are GTK/Ghostty-only. The experimental WebKitGTK browser pane remains in source behind the opt-in browser feature; it is not shipped in the AppImage or .deb for this alpha.

For the explicit terminal-only build used by release artifacts:

cargo run -p forktty-ui-gtk --no-default-features --features gtk-ghostty

For the source-only browser experiment, install WebKitGTK 6 development files and opt in:

cargo run -p forktty-ui-gtk --no-default-features --features browser

Build the Debian package locally:

bash scripts/build-deb.sh
sudo dpkg -i target/packaging/deb/forktty_*.deb

scripts/build-deb.sh and scripts/build-appimage.sh call scripts/ghostty-gtk-lib-probe.sh --ensure --print-path before packaging and fail if ghostty-gtk-embed.so cannot be built, located, or verified. The verified library is installed into usr/lib beside the forktty binary so installed terminal panes can load it through the binary RUNPATH without FORKTTY_GHOSTTY_GTK_LIB. Debian packages also install ForkTTY copyright/license information and third-party notices under /usr/share/doc/forktty/.

Build the AppImage locally (requires appimagetool on PATH, or APPIMAGETOOL=/path/to/appimagetool):

bash scripts/build-appimage.sh
./target/packaging/appimage/forktty-*-x86_64.AppImage

Set APPIMAGE_UPDATE_INFO=1 when building release-style AppImages with embedded update metadata; this requires zsyncmake on PATH and emits a matching .zsync file. The AppImage includes the same ForkTTY copyright/license information and third-party notices under usr/share/doc/forktty/ inside the AppDir/AppImage.

First Run

Check the environment

After install, confirm the runtime looks healthy:

forktty --version
forktty doctor

forktty doctor is a local-only inspector. It reports the resolved config, session, socket, hook config paths, and known recovery behaviors, and exits 0 on a clean environment or 2 with explicit warnings. Use forktty --json doctor when you also need the socket doctor report with environment, executable, hook config, MCP config, and agent skill paths.

Default workspace and shortcuts

ForkTTY opens the current directory as the main workspace. Use the command palette for most navigation and pane actions:

• Ctrl+Shift+P: command palette
• Ctrl+Shift+N: new workspace
• Ctrl+Shift+O: open workspace
• Ctrl+Shift+H: split pane right
• Ctrl+Shift+E: split pane down
• Ctrl+Shift+T: new tab in the focused pane
• Ctrl+Shift+W: close pane
• Ctrl++/Ctrl+=, Ctrl+-, Ctrl+0: zoom terminal panes
• Ctrl+B or F9: toggle workspace sidebar
• Agents: titlebar button or command palette
• Ctrl+Shift+M: notifications
• Ctrl+? (F1 also works): keyboard shortcuts
• Ctrl+,: settings
• F10: main menu when focus is outside terminal content; terminal panes keep plain F10 for TUI apps

Socket CLI

The same forktty binary speaks the local socket API. Diagnostic commands work even when the GTK app is not running:

forktty --help
forktty --version
forktty doctor          # local diagnostics, no socket required
forktty ping            # check the running daemon

Workspace, surface, worktree, notification, and metadata commands talk to the live socket:

forktty list
forktty focus "Workspace 2"
forktty ssh user@example.com
forktty surfaces --workspace-name main
forktty agents --workspace-name main
forktty agent-health --workspace-name main
forktty resume-agent --surface-id <surface-id>
forktty agent-reclaim-plan --workspace-name main --min-idle-ms 600000
forktty read-screen --surface-id <surface-id>
forktty capture-tail --surface-id <surface-id> --lines 80
forktty tree --workspace-name main
forktty top --workspace-name main
forktty split-surface --axis vertical
forktty new-tab
forktty send-text "cargo test\n"
forktty worktree-status
forktty notify --title "Input needed" --kind prompt "Blocked on test fixture"
forktty set-status --key agent:codex --label Codex --value Running --color blue
forktty set-progress --key build --label Build --value 42 --total 100
forktty statusline
forktty status explain --tail-lines 20
forktty status watch --count 3 --interval-ms 2000
forktty identify --json
forktty wait agent-status --status needs_input --timeout-ms 30000
forktty context-snapshot --workspace-name main --tail-lines 0 --json
forktty task-plan "fix this bug and verify it" --cwd "$PWD" --json
forktty task-apply --run-id router-run-1 --plan-json '<plan-json>' --request-approval "fix this bug and verify it"
forktty feed respond '<approval-id-from-request>' --decision approve
forktty task-apply --run-id router-run-1 --plan-json '<plan-json>' --approval-id '<approval-id-from-request>' "fix this bug and verify it"
forktty task-apply --run-id router-run-1 --plan-json '<plan-json>' --approved start_run "fix this bug and verify it"
forktty task-apply --run-id router-run-1 --plan-json '<team-plan-json>' --cwd /path/to/repo --approved start_run,launch_parallel_workers --submit "review this implementation"
forktty workflow-loop-set loop-runtime --stage verify --iteration 2 --max-iterations 4
forktty team ask review-team claude-review --agent claude --task-id review-head --prompt "Review HEAD read-only" --submit
forktty team review review-team claude-review --agent claude --task-id review-head --commit HEAD --submit
forktty team watch review-team --stale-after-ms 120000 --limit 10
forktty team finish review-team --dry-run
forktty team finish review-team --close-workers
forktty examples
forktty completions bash
forktty log --level warn "Waiting for reviewer input"
forktty notifications
forktty capabilities
forktty events

ForkTTY agents and scripts can ask the local task router for a strategy before choosing manual modes. forktty task-plan "fix this bug and verify it" --json and the MCP task_strategy_plan tool return whether the task should stay solo, use a workflow loop, add a reviewer, create a team, or isolate work in a worktree. The planner is read-only, returns the selected router profile (balanced, fast, conservative, parallel, or review_heavy) plus ranked candidate strategy scores with factor breakdowns, scores each ready harness assignment by role with factor breakdowns, uses configured team provider order as the assignment tie-break, respects each harness's declared parallel session capacity before selecting multi-role parallel plans, infers dirty git state from the selected surface/workspace cwd when repo_dirty/--repo-dirty is omitted, or from an explicit absolute --cwd / MCP cwd inside a Git repository already represented by an open ForkTTY workspace, surface, or effective project cwd. It also infers likely user-visible edit intent and clear router profiles from the goal when omitted, infers advisory last-known-good strategy/harness evidence from completed task-strategy workflows when available, and keeps reviewer strategies honest by including a reviewer assignment. Pass --profile <profile> or MCP/socket router_profile only when you want to bias the automatic scorer explicitly. Scripts and MCP agents with real runtime evidence can pass --last-known-good-json/last_known_good to override or enrich the inferred advisory stickiness for a previously successful strategy or harness, and per-harness --harness-signals-json/harness_signals: cooldown is a soft assignment penalty, while locked_out excludes that harness for the current task/mode. Last-known-good only adds a small explainable score factor; readiness, cooldown, lockout, task fit, and approvals still win. After review, forktty task-apply --run-id <id> --plan-json '<plan-json>' --cwd <repo> --approved start_run "<goal>" and the MCP task_strategy_apply tool can stage the returned plan as visible workflow/team/task/message state. When a client wants ForkTTY to ask first, --request-approval/request_approval: true records a pending Feed approval and returns status: "blocked" without mutating workflow/team state; after forktty feed respond <approval-id> --decision approve, retry apply with --approval-id <approval-id>/approval_id. The returned approval id is bound to that run id, goal, plan, target scope, and submit mode; request a new approval when any of those change. An approval id requested for a superset of the currently missing approvals can satisfy the remaining approvals when the caller also supplies explicit attestations for part of the same request. Approval decisions are accepted only while the Feed approval is still pending; dismissed, stale, approved, or denied entries cannot be reused as fresh authorization. If a caller instead retries with an equivalent explicit --approved / approved attestation, ForkTTY dismisses the now-superseded pending Feed approval so it no longer raises a pending_approval risk flag. Apply recomputes dirty-repo edit isolation from the selected surface/workspace plus any explicit --cwd / cwd, and required approvals from the requested operation and effective plan shape, so dirty editing tasks cannot drop create_worktree and multi-worker submit cannot drop launch_parallel_workers from the JSON to bypass review. --approved/approved is a programmatic caller attestation; use --request-approval and retry with --approval-id when a Feed-backed human approval is required. Pass --cwd/cwd when the repository target differs from the selected ForkTTY pane; submit-mode workers launch there and role prompts include that cwd without creating a workspace or worktree. Pass --submit/submit: true for a supported team plan: ForkTTY launches visible worker panes, assigns tasks, queues deterministic role prompts, and dispatches them through the team mailbox with provider-aware Enter handling. If the plan has layers.worktree: true, pass --worktree-name <name>/worktree_name for an already-open ForkTTY worktree workspace; apply will reject missing or unopened worktrees before mutating state. Submit retries reuse a live deterministic worker only when its harness, role, task, worktree, launch cwd, effective target cwd, and status still match the current assignment; otherwise apply returns conflict before dispatching a prompt to the wrong pane. Worktree creation, push, merge, destructive commands, and out-of-scope edits require later explicit approval.

forktty team ask and forktty team review compose the existing team socket methods for common coordination flows: create/update the team, create the task, launch a fresh worker surface, assign the task after launch, queue the prompt, and dispatch it. Submit mode uses provider-aware terminal input: providers that accept it reliably receive text plus carriage-return Enter in one write, while Codex, Claude, and Pi receive the text, a short settle, and a separate Enter so their TUIs start the staged prompt reliably. Freshly launched provider TUI workers also get a brief initial prompt settle before the first dispatch. Human CLI output names the worker, selected provider when known, task, target surface, and whether the prompt was dispatched or submitted so a leader can tell which visible pane to monitor without opening JSON. Re-run them to launch a new worker; use team-message-send plus team-message-dispatch for follow-up prompts to an existing worker. Context snapshots include compact team_summaries rows so leaders can scan worker/task/message counts without first calling team.summary for each team; full team records with mailbox message bodies are included only when context.snapshot receives include_team_details: true. team_summaries rows include consistency_warnings when a team marked done still has active workers, open tasks, or pending messages, or when an active team has no open work left. Snapshots raise team_consistency_warning in risk_flags for the same condition. forktty team finish / team.finish performs the finalization preflight in one step: --dry-run shows the planned actions, blockers, and cleanup errors without mutation; non-dry-run finalization blocks on open tasks, pending messages, or live-looking workers unless --force is supplied, closes only current-runtime launch-owned disposable worker panes with --close-workers, normalizes missing worker surfaces as closed, and marks the team done. Context snapshots also include compact workflow_summaries rows. Full workflow records with durable memory, plan steps, and evidence are included only when context.snapshot receives include_workflow_details: true. Workflow summary rows include consistency_warnings, with workflow_consistency_warning in risk_flags when a running workflow has a completed plan or a terminal workflow still has open steps. Snapshot feed rows are compact by default: approvals and notifications remain, while status and progress trace rows are available with include_feed_trace: true. For closed loops, workflow.loop.set / workflow_loop_set / forktty workflow-loop-set records bounded loop metadata on an existing workflow: recipe, stage, iteration budget, stop reason, and compact gate counts. It is deliberately state-only: ForkTTY does not run a hidden scheduler, execute commands, push, merge, or approve actions from loop state. Snapshots include loop_summaries by default and raise loop risk flags for failed gates, blocked or human-needed stages, exhausted budgets, and stale workflow surface bindings. Loop summaries omit full workflow goals and gate notes; detailed workflow memory remains opt-in, and moving to a new iteration clears prior gate results and stop reason unless replacements are supplied in the same request. Workspace, surface, agent, and agent-health rows expose effective_project_cwd, preferring the tracked agent resume_cwd over the workspace directory when they differ; the GTK sidebar uses the same effective path for a focused tracked agent so a workspace launched from ~ can still display the project directory where the agent is actually working. That value is diagnostic context: worktree authorization and team worker launch placement use visible workspace roots, explicit launch/apply cwd, and the selected surface's recorded terminal cwd rather than hook-reported resume_cwd metadata. team.worker.health includes surface_present, surface_runtime_present, surface_ready, and a derived final_state such as shutdown_requested, closed, starting, surface_missing, or stale so cleanup decisions do not require interpreting raw worker fields; a worker surface is live only when it still exists in the workspace model and the terminal backend still reports a ready runtime. team.worker.shutdown uses the same provider-aware submit behavior by default; its close_surface option, exposed by CLI forktty team-worker-shutdown --close, immediately closes only surfaces that this ForkTTY runtime created through team.worker.launch, not manually attached user panes or stale persisted launch records after restart. For smaller control loops, system.identify/forktty identify returns the canonical target workspace/surface, caller id validation, current agent binding, and effective_project_cwd. ForkTTY pane environment ids are treated as caller context, so stale caller surface ids fall back to the active workspace focus instead of failing the read. forktty wait agent-status polls the persisted agent lifecycle with bounded timeout/interval values through short context.snapshot reads and no terminal text reads.

The titlebar Agent HUD shows persisted agent sessions across workspaces, highlights sessions that need input, and can focus or resume a tracked agent. The GTK HUD and sidebar collapse raw lifecycle values into scan-friendly labels such as Working, Needs input, Done, and Idle; the socket/CLI surfaces keep the raw lifecycle values (running, idle, needs_input, ended, or unknown) when a provider session id has been persisted. Hook events drive the live state, and terminal child exit marks attached sessions ended. forktty agents and forktty agent-health also expose persisted resume_cwd, last_activity_ms, source, response observed_at_ms, and nullable age_ms so delayed agent state can be compared with terminal evidence. Agent rows also include lifecycle_evidence, a diagnostic block that correlates the persisted lifecycle/freshness data with the current workspace/provider status row, permission mode, and resume-readiness reason when available. For Antigravity CLI, resume_cwd comes from the hook payload's workspacePaths, because agy executes the generated wrapper scripts from ~/.gemini/config rather than from the project directory. After a ForkTTY restart, restored terminal panes with a supported persisted agent session respawn through the provider's argv-only resume command, such as codex resume -C <resume_cwd> <session-id> when Codex hook metadata recorded the session working directory. Providers without a cwd flag, such as Claude Code, are spawned with resume_cwd as the child process directory. If a legacy ForkTTY session has no persisted resume_cwd yet, Codex resumes can still infer it from Codex's local session_meta JSONL when that project directory still exists. When provider hooks record the exact bypassPermissions mode, ForkTTY preserves that elevated mode on agent-health, explicit resume, and restore-time auto-resume by emitting the documented Codex and Claude Code bypass flags; other permission mode strings remain metadata and never become argv. forktty agent-reclaim-plan is read-only: it identifies old idle sessions that are locally resumable and explains why other sessions are protected, but it does not suspend or close panes.

Source-only builds with the browser feature expose experimental browser-pane automation over the same socket. This is intentionally not included in the prebuilt AppImage or .deb for the current alpha:

forktty browser open --profile Default https://example.com
forktty browser navigate <surface-id> https://www.rust-lang.org
forktty browser snapshot <surface-id>
forktty browser click <surface-id> <ref>
forktty browser fill <surface-id> <ref> "value"
forktty browser eval <surface-id> "document.title"
forktty browser profile list
forktty browser profile create Work
forktty browser history list
forktty browser bookmark add https://www.rust-lang.org
forktty browser import discover

The socket CLI and agent hook bridge are native Rust code in the forktty binary, so source checkouts and packaged builds do not require Node.js.

forktty capabilities includes the socket method list plus a provider_capabilities matrix for the supported providers (codex, claude, pi, opencode, and antigravity), including their launch program, whether ForkTTY has safe resume support, and whether the provider exposes a dedicated cwd resume flag. It also reports available_on_path, the resolved executable path when present, configured command overrides for harnesses installed outside the ForkTTY process PATH, disabled/missing reasons, and the active team_provider_policy used when team launches omit --agent. It also includes pty_persistence, a read-only diagnostic block showing whether general.persist_terminal_processes is configured and whether a supported broker such as dtach is currently available. Providers without a cwd flag, such as Claude Code, can still resume in ForkTTY's recorded process cwd when resume_cwd is available. Pi resume uses the documented pi --session <id> flow. forktty identify is the smallest CLI read for "where am I in ForkTTY?", while forktty wait agent-status gives scripts and agents a bounded lifecycle wait.

MCP server

ForkTTY can also expose the same local automation surface as MCP tools for agents that support stdio MCP servers:

forktty mcp                              # run the MCP server on stdio
forktty mcp setup                        # register Codex, Claude, Antigravity
forktty mcp setup codex claude --dry-run

The MCP server is local-only: it opens no network listener and bridges validated tool calls to the owner-only ForkTTY Unix socket. It exposes identify, workspace/surface inspection, topology tree, terminal read/capture, persisted agent-session inspection and explicit resume into a new tab, compact status summaries, pane split/focus/send-text, worktree create/attach/remove/merge, task strategy planning/apply, notifications, and status_set. Codex MCP setup preserves hand-edited TOML comments/formatting and uses the larger MCP config size budget for $CODEX_HOME/config.toml or ~/.codex/config.toml. If setup registers an AppImage launcher, the managed MCP server env includes APPIMAGE_EXTRACT_AND_RUN=1 so persistent MCP clients do not keep a FUSE AppImage mount alive. FORKTTY_SOCKET_PATH, FORKTTY_WORKSPACE_ID, and FORKTTY_SURFACE_ID are honored as defaults when the MCP host launches from a ForkTTY pane, except identify treats workspace and surface env ids as caller validation context and degrades stale caller surfaces to the active focus.

Spawned shells receive:

• TERM=xterm-256color
• COLORTERM=truecolor
• TERM_PROGRAM=ForkTTY
• TERM_PROGRAM_VERSION
• FORKTTY_WORKSPACE_ID
• FORKTTY_SURFACE_ID
• FORKTTY_SOCKET_PATH

That lets hooks and scripts target the current workspace without extra flags. Manual socket overrides must be absolute paths; blank or relative FORKTTY_SOCKET_PATH values are ignored so the app and CLI fall back to the default socket location.

Agent skills

Install the ForkTTY orchestration skill so Agent Skills-compatible tools and Claude Code know when to inspect ForkTTY context, use team workers, and compare hook/status/terminal state without being told the exact MCP call every time. The skill tells agents to call task_strategy_plan before choosing team, workflow loop, worktree, or multi-harness execution for non-trivial tasks, follow the selected router profile unless the user overrides it, rely on ForkTTY's completed-workflow last-known-good inference by default, pass explicit last-known-good or per-harness cooldown/lockout signals only when there is concrete evidence, respect harness parallel-session capacity, and use task_strategy_apply only after explicit approvals; apply stages by default, can request missing approvals through the Feed before mutating state, and can submit supported team plans as visible worker panes. Pass cwd to apply when the repo target differs from the selected ForkTTY pane; worktree-layer plans still require worktree_name to name an already-open ForkTTY worktree workspace. It still does not create worktrees. The skill also treats terminal tails and fetched public docs as untrusted input, requires durable team preflight for non-trivial worker launches, gives workers explicit role contracts, prefers already-open worktree workspaces for mutating parallel workers, uses lifecycle_evidence before declaring agent states stale, and tells agents to start hook/MCP/skill setup debugging with local forktty doctor diagnostics, setup dry runs, and isolated temporary config roots before changing real config files, without redirecting the live ForkTTY socket path when validating the currently running instance.

forktty skills setup                       # install agents + Claude targets
forktty skills setup agents --dry-run      # interoperable ~/.agents/skills target
forktty skills setup pi                    # Pi aliases the interoperable target
forktty skills setup claude
forktty skills remove agents

agents, codex, and pi target the interoperable ~/.agents/skills/forktty-agent-orchestration location. claude targets $CLAUDE_CONFIG_DIR/skills/forktty-agent-orchestration or ~/.claude/skills/forktty-agent-orchestration. Setup refuses to overwrite an unmanaged skill with the same name; managed updates/removals first move the old directory to a .bak-* backup. forktty skills setup --dry-run and forktty --json doctor report the managed skill status (missing, up_to_date, update_available, or unmanaged), source and installed checksums, and a forktty skills setup <target> repair command when the installed managed copy is stale.

Run forktty doctor --hooks to inspect local hook config paths. Run forktty --json doctor to inspect the hook config paths, MCP config paths, and agent skill directories ForkTTY resolves from the current environment.

Agent Hooks

Install hook templates for Codex, Claude Code, Antigravity CLI, and OpenCode:

forktty hooks setup                       # install default agents
forktty hooks setup codex                 # install just one
forktty hooks setup codex claude --dry-run
forktty hooks setup --full claude         # include Claude per-tool hooks
forktty hooks remove opencode             # remove ForkTTY-managed hooks/plugin
forktty hooks remove gemini               # cleanup legacy Gemini config only

--dry-run prints the would-be diff without touching disk. When setup records an AppImage launcher, generated hook commands set APPIMAGE_EXTRACT_AND_RUN=1 for the ForkTTY CLI child so short hooks do not keep a FUSE AppImage mount alive. Claude Code setup uses the lifecycle profile by default, avoiding blocking per-tool hooks on every tool call; pass --full to include PreToolUse, PostToolUse, PostToolUseFailure, and PostToolBatch. Re-running setup migrates Claude to the lifecycle profile unless --full is passed. hooks remove removes only ForkTTY-managed entries/plugins and leaves unrelated agent hooks in place. hooks remove gemini is kept only to clean legacy ForkTTY-managed ~/.gemini/settings.json entries from older releases; Gemini setup remains unsupported.

The installer merges commands into the agent's own config file:

Agent	Destination
Codex	$CODEX_HOME/hooks.json or ~/.codex/hooks.json
Claude Code	$CLAUDE_CONFIG_DIR/settings.json or ~/.claude/settings.json
Antigravity CLI	~/.gemini/config/hooks.json plus wrapper scripts in ~/.gemini/config/forktty-hooks.generated/
OpenCode	$OPENCODE_CONFIG_DIR/plugins/forktty.generated.js or ~/.config/opencode/plugins/forktty.generated.js

When HOME is overridden, the ~ defaults are resolved under that home directory. Existing configs are written atomically (tmp + rename) and a timestamped .bak-* backup is created when content changes.

On app startup, ForkTTY shows a reminder notification when no ForkTTY-managed agent hooks are installed, or when installed hooks point at a stale launcher.

Diagnose and exercise installed hooks:

forktty hooks doctor codex     # inspect socket, launcher, env, hook config
forktty hooks test codex       # round-trip a status update through the socket

Each agent's hook commands honor a per-agent disable variable:

• FORKTTY_CODEX_HOOKS_DISABLED=1
• FORKTTY_CLAUDE_HOOKS_DISABLED=1
• FORKTTY_ANTIGRAVITY_HOOKS_DISABLED=1
• FORKTTY_OPENCODE_HOOKS_DISABLED=1

Hooks report status, progress, logs, and prompt notifications through the same local socket pipeline. Manual hook-event commands can pass --socket <path> when they run outside a ForkTTY-spawned shell.

Features

• Native GTK4/libadwaita desktop shell with embedded Ghostty-backed terminals.
• Recursive split panes, pane focus/close, command palette, settings dialog, notification panel, and workspace sidebar.
• Quake/dropdown mode through config and F12 where global shortcuts are supported.
• Direct Unix socket JSON-RPC server for workspace (including SSH remote workspaces), surface, terminal read/capture, topology tree/top health inspection, pane-tab, notification, worktree, metadata, persisted agent-session inventory/resume, compact status summaries, context identify, read-only task strategy planning, event-stream, and capabilities; CLI wrappers add bounded lifecycle waits over read-only socket calls.
• Agent HUD in the GTK titlebar for lifecycle, last activity, attention, focus, and resume across workspaces.
• Git worktree create/attach/remove/merge/status with dirty-state protection and hook execution inside verified worktrees. Setup hooks are advisory; teardown hook failures or teardown-created dirty state block removal.
• Session restore for workspace order, active workspace, pane tree, focused surface, cwd, branch, and worktree metadata.
• Prompt-aware notifications from ForkTTY hooks and terminal events, bounded visible prompt fallback, Ghostty bell, and hook/socket events. The notification panel groups prompts/current-workspace/history and its latest-target action prioritizes unread prompts before lower-urgency history.
• Source-only experimental WebKitGTK6 browser panes (behind the browser feature) with scriptable snapshot/click/fill/eval verbs, per-profile persistent WebKit sessions, profile CRUD, history/bookmark socket plus CLI access, and history/bookmark import from local Firefox/Chromium-family profiles.
• Bounded config/session/socket handling and local-only privacy defaults.

Configuration

Config file: ~/.config/forktty/config.toml. All fields are optional. The Settings dialog intentionally does not edit general.shell; change the shell by editing this file or your login shell environment.

[general]
shell = "/bin/bash"
worktree_layout = "nested" # "nested", "sibling", or "outer-nested"
enable_pr_lookup = false
notification_command = ""
persist_terminal_processes = false

[appearance]
persistent_scrollback_lines = 0
sidebar_position = "left" # "left" or "right"
sidebar_visible = true
window_mode = "normal" # "normal" or "quake"

[notifications]
desktop = true
sound = true
blocked_terminal_apps = []
blocked_terminal_types = []

[team]
default_agent = "auto" # "auto", "codex", "claude", "pi", "opencode", or "antigravity"
provider_order = ["codex", "claude", "pi", "opencode", "antigravity"]
auto_fallback = true
disabled_agents = []

[updates]
auto_check = true

[telemetry]
anonymous_ping = true

notification_command is split with shell_words; ForkTTY does not use sh -c. The first token must be an absolute executable path. Notification title/body are passed through FORKTTY_NOTIFICATION_TITLE and FORKTTY_NOTIFICATION_BODY; OSC 99 f/t metadata is exposed as FORKTTY_NOTIFICATION_TERMINAL_APP and FORKTTY_NOTIFICATION_TERMINAL_TYPES_JSON. blocked_terminal_apps and blocked_terminal_types suppress terminal-originated OSC 99 notifications whose exact f application or t type matches one of the listed strings.

The [team] section controls visible team worker launch defaults. Omit --agent or pass --agent auto to let ForkTTY choose the first configured provider whose harness is resolvable from the ForkTTY process PATH or a configured provider_commands override; use an explicit provider to override the policy. Settings > Agents shows the same default, fallback, provider order, disabled providers, direct command overrides, and harness detection.

persistent_scrollback_lines is off by default; when set above 0, ForkTTY stores a bounded plain-text tail per surface in session-v2.json and restores it before the fresh shell starts. persist_terminal_processes is also off by default and can be toggled from Settings > Worktrees; when set to true and dtach is available on an absolute PATH entry, plain terminal panes run under a detach/reattach broker so generic shells, dev servers, REPLs, editors, and long-running commands can survive a GTK UI restart and re-attach on relaunch. AppImage-launched brokers close inherited AppImage runtime file descriptors before dtach starts, so surviving brokers do not keep the FUSE AppImage mount alive after the GTK window closes. Explicit pane close/restart terminates the matching ForkTTY-managed broker process tree and removes the per-surface broker socket, so a later reused surface id starts fresh instead of attaching to stale detached state. Disabling the setting cleans stale detached sessions while preserving currently visible panes until they close; closing the GTK window with the setting disabled cleans visible managed brokers too. Starting with the setting disabled cleans old managed sessions before restore. Agent panes continue to use provider resume, and SSH, browser, project-action, and team-worker panes are not wrapped. If dtach is missing, ForkTTY falls back to normal ephemeral terminal spawning. Live embedded panes follow Ghostty's scrollback-limit budget (10 MB by default) and scrollbar = system|never preference, so mouse-wheel scrollback and the vertical scrollbar come from Ghostty config while legacy ForkTTY scrollback_lines is treated as a compatibility key and omitted from new saves. Terminal font, colors, cursor/faint opacity, bell behavior, mouse scroll multiplier, cell size adjustments, and inactive split dimming come from Ghostty's config (~/.config/ghostty/config.ghostty or the legacy ~/.config/ghostty/config) when present, including config-file, theme, named colors, 16-color palette entries, cursor-opacity, faint-opacity, bell-features, mouse-scroll-multiplier, adjust-cell-width, adjust-cell-height, unfocused-split-opacity, and unfocused-split-fill; no system Ghostty install is required. Legacy ForkTTY font/theme/scrollback/bell/renderer keys are kept only for config compatibility and omitted from new saves. Terminal panes require the embedded Ghostty GTK widget; if ghostty-gtk-embed.so is missing or fails to load, panes report a spawn failure rather than opening with the old renderer.

updates.auto_check = true checks GitHub Releases no more than once every 24 hours. The stamp is written on both success and failure so offline machines are not probed on every launch.

telemetry.anonymous_ping = true sends at most one GTK-startup ping per UTC day to https://forktty.dev/api/telemetry/ping. The JSON body is limited to schema, kind, app, version, and date; it contains no install id, username, hostname, cwd, repository path, branch, shell, agent metadata, terminal buffer, socket payload, or crash data. Set it to false to disable the ping.

See SPEC.md for the full list of validated fields and their bounds.

Session Restore

GTK/Ghostty sessions are stored as:

~/.local/state/forktty/session-v2.json

ForkTTY imports legacy session.json when present, but saves the native runtime as v2. By default restore re-spawns fresh Ghostty-backed terminals; scrollback restore is limited to the opt-in plain-text tail controlled by persistent_scrollback_lines. With general.persist_terminal_processes = true and dtach available, plain terminal process trees survive through the broker and restored panes re-attach by persisted surface id. If the setting is false on startup, old ForkTTY-managed broker sessions are cleaned before restore. Corrupt or structurally invalid session files are quarantined.

Security Summary

• Local Linux desktop threat model; same-user processes remain part of the local trust boundary.
• Unix socket defaults to $XDG_RUNTIME_DIR/forktty.sock with /tmp/forktty-<uid>/forktty.sock fallback and owner-only permissions.
• Socket request lines, config files, and session files are size bounded.
• Shell paths, hooks, and custom notification commands use validated argv execution, not shell pipelines.
• Worktree names, socket-provided repo paths, and hook locations are validated before mutation or execution.
• ForkTTY makes no crash-reporting or product event-tracking network calls. With telemetry.anonymous_ping = true, the GTK app sends one anonymous daily usage ping; set it to false to disable it. With updates.auto_check = true, the GTK app checks GitHub Releases at most once per day; browser panes and PR lookup remain optional/user-directed network paths. The shipped AppImage and .deb do not embed a browser runtime.

See SECURITY.md and PRIVACY.md.

Known Limitations

• Linux only. There are no supported macOS or Windows builds.
• libadwaita 1.4+ is required by the native terminal integration.
• The AppImage ships a bundled GTK4/libadwaita fallback plus Ghostty and gtk4-layer-shell, but prefers a host GTK stack when available and still relies on the host's glibc, fontconfig, OpenGL/Vulkan/Mesa driver stack, display-server libraries, and desktop session services. Test it on the target distro/desktop environment; prefer the .deb on Debian/Ubuntu when package-manager integration matters.
• PTY/process persistence is opt-in for plain terminal panes through general.persist_terminal_processes and requires dtach; by default restored sessions spawn fresh shells. Scrollback persistence is opt-in, plain-text only, and bounded.
• OSC 9 and basic OSC 99 terminal notifications are parsed from the Ghostty-owned PTY stream and rate-limited per surface; OSC 99 title/body base64 payloads and same-id title/body chunks are decoded with multipart title/body kept separate, same-id update/close controls affect ForkTTY's notification model, and in-app Open/Dismiss/Clear All plus basic same-id buttons can send OSC 99 reports. Targeted desktop notifications expose a best-effort Open action, notification dismiss/clear closes matching desktop and OSC 99 tracked notifications, prompt feed approvals distinguish pending/approved/denied/dismissed/stale, icon names, application-name icon fallback, application/type filtering metadata, occasion filtering, urgency, expiry, and sound metadata feed notification handling, positive w expiry values dismiss in-app notifications, and bounded p=icon data can be cached by g; broader chunk lifecycle behavior remains partial.
• Quake global shortcuts and layer-shell placement depend on desktop/compositor support.
• Agent hibernation/suspend UI, provider-side session existence checks, full theme customization, multi-window, and browser history/bookmark GTK address-bar integration are backlog items.
• Browser panes are source-only and experimental in this alpha; use --features browser only when intentionally testing that path.

Troubleshooting

• forktty doctor is the first stop: it explains config, session, socket, and hook config problems before they trigger a launch failure. Use forktty --json doctor for socket, environment, executable, hook config, MCP config, and skill path diagnostics.
• If terminal panes report ghostty-gtk-embed.so as missing in a source tree, run git submodule update --init vendor/ghostty and scripts/ghostty-gtk-lib-probe.sh --ensure --print-path. For packaged builds, rebuild or reinstall with bash scripts/build-deb.sh or bash scripts/build-appimage.sh; the packagers install the verified library into usr/lib.
• If the GTK app refuses to start, run it from a terminal to see GLib/GTK error output, then re-run forktty doctor.
• The local socket lives at $XDG_RUNTIME_DIR/forktty.sock (or /tmp/forktty-<uid>/forktty.sock). Stale or foreign sockets are refused on startup; remove them by hand only after confirming no other ForkTTY instance owns them.
• A corrupt ~/.config/forktty/config.toml or ~/.local/state/forktty/session-v2.json is renamed aside as *.bad-<timestamp> so the app can start with defaults; the rename reason is logged to stderr.
• Local logs live under ~/.local/share/forktty/logs/.

Support

For usage questions and bug reports, start with SUPPORT.md and include the output of forktty doctor, your distro/desktop environment, install method, and the exact command or workflow that failed. Security reports should follow SECURITY.md.

Contributing

Useful commands:

cargo fmt --all --check
git submodule update --init vendor/ghostty
cargo run -p xtask -- check
scripts/ghostty-gtk-lib-probe.sh --ensure --print-path
cargo test --workspace --all-targets --no-default-features --features gtk-ghostty
cargo clippy --workspace --all-targets --no-default-features --features gtk-ghostty -- -D warnings
cargo build -p forktty-ui-gtk --no-default-features --features gtk-ghostty
scripts/gtk-ghostty-smoke.sh
cargo test -p forktty-ui-gtk --all-targets --no-default-features --features browser
desktop-file-validate packaging/linux/dev.forktty.forktty.desktop
bash scripts/build-deb.sh
bash scripts/build-appimage.sh

See SPEC.md, ROADMAP.md, and docs/native-gtk-ghostty.md. Use docs/release-qa.md before tagging alpha releases.

Inspiration

Built from scratch for Linux, inspired by cmux and other multi-agent terminal workflows.

License

GNU Affero General Public License v3.0 (AGPL-3.0-only)