Agents and models
Feature matrix
User-facing feature coverage across clients and runtimes.
This page summarizes the main user-facing capabilities currently surfaced in Happier.
Status legend:
- Stable: intended for regular use
- Experimental: available, still being hardened
- Capability-driven: depends on backend/provider support
Core capabilities
| Capability | Status | Where it works | Notes |
|---|---|---|---|
| Multi-server profiles + switching | Stable | App, Web, CLI | Accounts and runtime state are scoped per server. |
| Session sharing + collaboration | Stable | App, Web | Share sessions with friends/teammates and manage access. |
| Session read/unread state | Stable | App, Web, Mobile app | Unread badges plus Mark as unread/read actions in session lists, context menus, headers, and Session info. |
| Happier sessions + resume | Stable | App, Web, CLI | Resume inactive Happier-managed sessions when the provider/backend supports vendor resume for that session. |
| New session shortcuts | Stable | App, Web, Mobile app | Start a new session from a project or Session info while reusing the relevant session setup; existing composer draft content is preserved while launch selections are replaced. |
| Session handoff between machines | Capability-driven | App, Web | Move a live session to another machine while keeping the same session id. Claude and OpenCode are supported; Codex is experimental. |
| Direct provider sessions | Experimental | App, Web | Browse provider-native sessions, open them directly, and optionally sync them into Happier. |
| Mobile session cockpit | Stable | Mobile app, mobile web | Default phone session layout with bottom tabs for agent chat, Files, Git, open details tabs, and Terminal when available. |
| Embedded terminal | Experimental | App, Web, Mobile app | Session-owned terminal dockable to bottom/sidebar/details; requires a connected daemon and reachable machine. |
| Pending queue | Stable | App, Web, CLI runtime | Queue, reorder, edit, remove, and send-now workflows. |
| In-flight steering while busy | Capability-driven | App, Web, CLI runtime | When supported by backend/runtime, messages can steer an active turn instead of waiting in queue. |
| Git/file manager | Stable | App, Web, Mobile app | Browse/search files, upload/download, rename/delete, open previews/editors, inspect metadata, open markdown file links, initialize Git repositories, and review changed files from the session UI. |
| Git write operations | Experimental | App, Web, Mobile app | Stage/unstage/commit/pull/push/revert plus selected-for-commit, branch publish/switch/stash, branch checkout recovery, and commit-message-generation workflows behind the Git operations feature toggle. |
| Turn/session/selected changed-file scopes | Capability-driven | App, Web, Mobile app | Git changed-files scope dropdown can show repository changes, latest-turn changes, session-attributed changes, and selected-for-commit files when data is available. |
| SCM hosting providers | Experimental | App, Web, daemon | Detect GitHub/GitLab/Bitbucket remotes, publish local repositories to GitHub, and open/reuse/checkout PRs or MRs where provider auth is available. |
| Review comments | Experimental | App, Web | Add line-specific comments to file/diff lines, select which comments are sent, reuse saved workspace comments in new sessions, and jump back to commented files from the transcript. |
| Tool timeline normalization | Stable | App, Web, CLI runtime | Provider tools are normalized to canonical UI tool types. |
| Subagent timeline visibility | Capability-driven | App, Web | When providers expose subagents, Happier shows their activity in-session. |
| Tool detail controls (title/summary/full) | Stable | App, Web | Configure default/per-tool timeline detail levels. |
| Turn-level change summaries | Capability-driven | App, Web | Per-turn summary and diff rendering quality depends on provider/runtime payloads. |
| Permission modes | Capability-driven | App, Web, CLI | Effective behavior varies by provider/backend capabilities. |
| Model/mode selection + favorites | Capability-driven | App, Web, CLI | Model lists can be dynamic or static; favorites are available from the new-session engine picker. |
| Connected services | Stable | App, Web, CLI, daemon | Connect provider subscriptions, API keys, and GitHub tokens once, then reuse them across supported backends, sessions, and source-control workflows. |
| Connected-services auth picker | Stable | App, Web | New-session auth picker shows only backend-compatible connected services and profiles. |
| Connected-services quotas | Capability-driven | App, Web, daemon | Quota badges and profile detail meters currently exist for openai-codex, claude-subscription, and gemini. |
| Local memory search | Experimental | App, Web, daemon | Opt-in machine-local transcript search with light/deep indexing, backfill controls, and optional embeddings reranking. |
| Pets | Experimental | App, Web, Mobile app, Desktop app, daemon | Optional pet companions with built-in pets, Codex-compatible imports, desktop overlay bubbles, mobile/native drag, per-device size, and server-side feature controls. |
| ACP backends | Experimental | App, Web, CLI runtime | Add arbitrary ACP-compatible CLIs through Custom ACP and use each configured backend as a first-class backend choice. |
| Installables | Stable | App, Web, daemon | Manage machine-local tools such as Codex ACP and optional GitHub CLI (gh) with per-machine install/update policy. |
| Server feature flags | Stable | App, Web, Server | Server can disable features (for example social/voice/bug reports) and clients adapt UI accordingly. |
| Notification routing to session/server | Stable | App, Web | Notification taps route to the correct session/server; mobile also supports permission Allow / Deny and action-request Answer buttons with safe server-aware routing. |
| In-app bug reports + diagnostics | Stable | App | Submit issue reports with optional diagnostics; server can disable upload/report UI. |
| Voice: Happier Voice | Capability-driven | App, Web | Managed realtime ElevenLabs voice; requires server voice config and feature enablement. |
| Voice: BYO ElevenLabs | Stable | App, Web | Uses your own ElevenLabs account/API key, supports voice previews, and can provision/update a Happier-compatible ElevenLabs agent. |
| Voice: Local voice | Experimental | App, Web | Mix device, OpenAI-compatible, Google, and local-neural STT/TTS providers; supports direct-to-session and agent conversation modes. |
| Voice: Local neural speech | Experimental | App, Web | Kokoro local neural TTS works on web and native; Sherpa local neural STT currently requires a native build. |
Which agent supports what
Agent-by-agent capabilities — resume, fork, steering, plan mode, media, models, authentication — live in Agent capabilities, which is generated from the agent manifest so it cannot drift from the build you are running. Setup and known limits for each one are on its own page under Coding agents.
Related
- Permissions
- Custom ACP
- Model and engine selection
- New session shortcuts
- Session handoff
- Session read and unread state
- Pending queue
- Steering while busy
- Embedded terminal
- Tool timeline & normalization
- Server feature flags
- Bug reports
- Git & file browser
- Connected services
- Installables
- Review comments
- Local memory search
- Pets
- Notifications
- Update channels and update behavior