Openseek
OpenSeek - 广度求索: open-source TUI coding agent with multi-provider routing, MCP, LSP, and Plan/Agent/YOLO modes.
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What is Openseek?
OpenSeek is a lightweight, scriptable terminal coding agent that runs locally on your machine. It is designed for developers who live in the terminal and want a coding companion without proprietary cloud services, sign-in requirements, or vendor lock-in. The tool supports multi-provider routing across five backends including OpenAI-compatible, Anthropic, Bedrock, Vertex, and Azure, allowing users to swap models per task or session without rewrites.
Key features include 50+ built-in tools (file edits, shell, search, fetch, refactor, run/test, git, browser), 100+ discoverable slash commands that are scriptable and composable, MCP-native client support for Model Context Protocol, LSP feedback in the loop for diagnostics/hovers/references, and a headless HTTP/SSE API for running as a service in CI or custom frontends. OpenSeek offers three autonomy modes: Plan (read-only thinking that drafts plans without writing files), Agent (confirm-on-write as the default with veto power), and YOLO (auto-approve everything for CI runs or sandboxes).
OpenSeek is built for engineers, developers, and researchers who want control over their coding agent. It is open source under MIT license, requires no accounts or SaaS round-trip, and your code never passes through OpenSeek servers since you bring your own API key. The tool runs on macOS, Linux, and WSL2 for both arm64 and x86_64 architectures, written in TypeScript with Bun runtime for fast startup.
The agent is provider-neutral by design, allowing you to mix providers per task—using a cheap model for planning, a frontier model for agent work, and local models for offline use. Skills are first-class citizens, and the tool is highly extensible through MCP client + skills + custom tools, familiar to those who have written tools for Claude Code or Codex CLI.
Openseek pricing
Pricing model: Freemium
Free and open source under MIT license. No paid plans, no subscription fees. The tool itself is completely free—users only pay for the LLM API usage from their chosen provider (Anthropic, OpenAI, Bedrock, Vertex, Azure, or OpenAI-compatible services). There are no OpenSeek servers or SaaS costs since everything runs locally on your machine with your own API key.
Openseek pros
- Open source under MIT license with no restrictions on farming or selling builds
- Multi-provider routing across five backends without vendor lock-in
- 50+ built-in tools covering real engineering workflows
- 100+ discoverable, scriptable, composable slash commands
- MCP-native client for Model Context Protocol integration
- LSP feedback in the loop with diagnostics, hovers, references
- Headless HTTP/SSE API for CI, editors, and custom bots
- Three autonomy modes (Plan, Agent, YOLO) for different risk levels
- No sign-in required, no proprietary cloud round-trip
- Your code never passes through OpenSeek servers
- Fast startup time with Bun runtime and native TypeScript
- Works on macOS, Linux, WSL2 for arm64 and x86_64
- Swap models mid-session without rewrites
- Skills are first-class with dedicated workspace package
- Provider-neutral design brings your own API key directly
Openseek cons
- Requires Bun ≥ 1.3 installation as a dependency
- Terminal-based TUI may not suit GUI-preferring users
- You must bring and manage your own API keys
- No central OpenSeek backend means no managed service option
- Version 0.1 indicates early stage development
- Learning curve for slash commands and skills customization
- Headless mode requires manual HTTP/SSE configuration
- Limited to five provider backends (no custom provider support beyond OpenAI-compat)
Frequently asked questions about Openseek
How is OpenSeek different from Claude Code, Aider, or Codex CLI?
OpenSeek is provider-neutral by design with no SaaS, no central runtime, and no vendor commitments. You can bring any of five backends, swap them mid-session, and run the agent headlessly behind your own API, unlike competitors that may lock you into specific providers or cloud services.
Why does OpenSeek use Bun instead of Node?
Bun provides faster startup time, native TypeScript support, native fetch, and a workspace runner that doesn't need 14 plugins. The TUI is a 14-package monorepo that Bun handles without ceremony compared to Node's requirements.
Is my code sent to a third party?
Only to the provider you configure. There is no OpenSeek backend. Your file edits, shell calls, and prompts go from your terminal directly to the LLM endpoint of your choice without passing through OpenSeek servers.
Can I use OpenSeek in CI?
Yes—'openseek serve --http' exposes a streaming HTTP/SSE runtime. You can pipe a goal in and get a structured event stream out. Run it inside Docker, GitHub Actions, or your own scheduler for automated coding tasks.
How extensible is OpenSeek?
It uses MCP client + skills + custom tools architecture. If you've written tools for Claude Code or Codex CLI, the wiring is familiar. Skills are first-class citizens with the Skills package being one of the 14 workspaces in the monorepo.
What's the license for OpenSeek?
MIT license. You can fork it, ship it, embed it, or sell something built on top of it. The only ask from the maintainers is to tell them what you built.
What are the three autonomy modes in OpenSeek?
Plan mode is read-only thinking that surveys the repo, drafts a plan, and suggests edits without writing files. Agent mode is confirm-on-write (the default) where the agent picks tools but you keep veto on writes, shell, and irreversible ops. YOLO mode auto-approves everything, best for CI runs, sandboxes, or when you've already pushed today.
Which providers and models does OpenSeek support?
OpenSeek supports five backends: Anthropic (Claude 4.x with streaming and tool use), OpenAI (GPT-5.x with responses API and function calls), Bedrock (Nova/Claude/Llama via AWS), Vertex (Gemini with MakerSuite for enterprise), Azure (OpenAI on Azure with region pinning), plus OpenAI-compat for vLLM, llama.cpp, Mikan Cloud, and DeepInfra.
How do I install OpenSeek?
First install Bun ≥ 1.3 using 'curl -fsSL https://bun.sh/install | bash' or 'brew install oven-sh/bun/bun'. Then install OpenSeek globally with 'bun install -g openseek' or 'npm i -g openseek'. Finally launch the TUI with 'openseek'. For headless mode, use 'openseek serve --http :7531'.
What platforms and architectures does OpenSeek support?
OpenSeek runs on macOS, Linux, and WSL2. It supports both arm64 and x86_64 architectures. The tool is written in TypeScript and requires Bun runtime version 1.3 or higher.