Litespeed – a local coding agent with multi-model workflows

BerriAI released Litespeed, a local coding agent for the terminal and browser built around multi-model workflows, distributed as a macOS package with runtimes included so no Node or npm setup is required. Litespeed connects through LiteLLM, OpenAI-compatible APIs, native Anthropic, or ChatGPT device sign-in, and its recommended Sidekick Fusion arrangement pairs a strong driver model for planning and review with a cheaper sidekick for implementation, while the experimental LiteFusion routes 63 task categories to specific models and reasoning levels. The agent runs a local backend automatically, serves a browser UI at http://localhost:3210, and keeps saved sessions and settings outside the application package.

A local coding agent for your terminal and browser, built around multi-model workflows . Use one model or combine a driver with sidekicks, workers, or experts. Follow their work, approve changes, and review the result in one conversation. Pairing models lets a faster, cheaper model handle routine work while a stronger model handles planning or difficult tasks, which can reduce cost and wait time. Connect through LiteLLM, OpenAI-compatible APIs, native Anthropic, or ChatGPT device sign-in. Your project stays on your machine; prompts and selected context go to your chosen provider. Download the macOS package with its runtimes included—no Node or npm setup: curl -fsSL https://github.com/BerriAI/litespeed/releases/latest/download/install.sh | sh Open a new terminal , then run it from the project you want to work on : cd /path/to/your/project litespeed The installer sets up the litespeed command for new terminal windows zsh or Bash . If you use the same terminal window where you installed it, run export PATH="$HOME/.local/bin:$PATH" first. Litespeed starts its local backend automatically. Updates appear in both UIs, or run litespeed update . Saved sessions and settings stay outside the application package. See installation, updates, and the source-build alternative https://github.com/BerriAI/litespeed/blob/main/docs/installing.md . Packages support Apple silicon and Intel Macs. Git and your project's development tools remain separate. Litespeed has its own command, separate from the LiteLLM gateway CLI https://docs.litellm.ai/docs/proxy/management cli . If you used an earlier version of this agent, follow the upgrade guide https://github.com/BerriAI/litespeed/blob/main/docs/upgrading.md to carry over saved sessions and configuration. 1. On your first launch, choose your setup, connect your LiteLLM gateway base URL and API key , and pick your models. Sidekick Fusion is recommended: choose a strong driver to plan and review, and a cheaper sidekick to handle implementation. LiteFusion is experimental ; its task-specific routing policy is available for evaluation. Choose Single model if you prefer one model for everything. Litespeed remembers the connection and models; running litespeed in another project opens chat directly. Gateways that do not require a key can leave it blank. 2. Use Models or /models to change your arrangement. Ask first is the default; Allow all tools is available in permissions. The full setup is available from the web sidebar or /setup . If you already use Claude Code or Codex skills, /skills or Settings → Project profiles offers Import a Claude/Codex skill… to copy one into the project — see Project profiles and skills https://github.com/BerriAI/litespeed/blob/main/docs/profiles.md . 3. Type a task. Build can edit files and run commands; Plan uses read-only tools. Type / for command suggestions in either client; use ↑/↓ , Tab or Enter to complete, and Esc to dismiss. Ctrl+P opens terminal commands and navigation. See the terminal guide https://github.com/BerriAI/litespeed/blob/main/docs/tui.md for shortcuts, resuming sessions, and configuration. Once Litespeed is running, open http://localhost:3210 http://localhost:3210 . The browser and terminal share saved sessions, providers, and model settings. For a web-only session, run litespeed serve . For development, use npm run dev from the checkout. See development and updating https://github.com/BerriAI/litespeed/blob/main/docs/development.md . | Architecture | How it works | |---|---| | Single model | One model investigates, implements, and checks the task. | | Sidekick Fusion · Recommended | A strong driver plans and reviews; a cheaper sidekick keeps context across handoffs. | | LiteFusion · Experimental | One persistent lead routes 63 task categories to specific models and reasoning levels, with one shared hard/escalation map. | | Team Fusion | A strong driver assigns fresh cheaper workers, runs independent work in parallel, and verifies the combined result. | | Expert Fusion | A cheaper driver coordinates fresh strong experts and verifies their work. Independent assignments can run in parallel. | Choose any connected model for each role. An optional Planner model handles Plan mode separately. Litespeed uses your last chosen model arrangement for new sessions across workspaces; existing sessions keep their settings. Cost and quality depend on the models and task. See architecture details and limits https://github.com/BerriAI/litespeed/blob/main/docs/architectures.md . Shunt sends large reads and routine generation to a separate model. Off by default; enable it in Advanced settings during setup or in Models, in either client. How it works and measured results https://github.com/BerriAI/litespeed/blob/main/docs/shunt.md . Session goals /goal keep an objective moving across turns. There is no turn limit unless you set one. Context compaction https://github.com/BerriAI/litespeed/blob/main/docs/context-management.md makes room during long tasks automatically. - Using Litespeed https://github.com/BerriAI/litespeed/blob/main/docs/usage.md : queue follow-ups, steer a response, answer questions, manage context, and customize projects. - Providers https://github.com/BerriAI/litespeed/blob/main/docs/providers.md · CLI and scripting https://github.com/BerriAI/litespeed/blob/main/docs/cli.md · Terminal controls https://github.com/BerriAI/litespeed/blob/main/docs/tui.md - Permissions https://github.com/BerriAI/litespeed/blob/main/docs/permissions.md · Undo/redo, recovery, and local data https://github.com/BerriAI/litespeed/blob/main/docs/local-data.md - Project profiles and skills https://github.com/BerriAI/litespeed/blob/main/docs/profiles.md · MCP connections https://github.com/BerriAI/litespeed/blob/main/docs/mcp.md · Hooks and plugins https://github.com/BerriAI/litespeed/blob/main/docs/design-hooks-plugins.md - Context management and harness comparison https://github.com/BerriAI/litespeed/blob/main/docs/context-management.md · Concurrent tasks https://github.com/BerriAI/litespeed/blob/main/docs/concurrency.md - Agent memory https://github.com/BerriAI/litespeed/blob/main/docs/memory.md · History search https://github.com/BerriAI/litespeed/blob/main/docs/search.md · Research tasks https://github.com/BerriAI/litespeed/blob/main/docs/delegation.md - Feature coverage and known gaps https://github.com/BerriAI/litespeed/blob/main/docs/coverage.md · Development and tests https://github.com/BerriAI/litespeed/blob/main/docs/development.md Approved commands run with your local user’s capabilities; permissions are not a sandbox. Keep the server local. Provider keys stay server-side, and provider usage may incur charges. Litespeed is licensed under Apache-2.0 https://github.com/BerriAI/litespeed/blob/main/LICENSE . Bundled themes and fonts retain their original licenses; see third-party notices https://github.com/BerriAI/litespeed/blob/main/THIRD PARTY NOTICES.md .