Cline passed 5 million installs in the VS Code marketplace.
And open-source AI coding agents like it now run inside the editor, the terminal. And the IDE plugins you already open every day. Here’s the short answer for 2026: Cline leads the editor-embedded agents, OpenCode is the terminal favorite with 162k+ GitHub stars by one count. And OpenHands paired with Ollama runs a coding agent entirely on your own hardware. All of them are open source, all of them let you bring your own model. And several run fully air-gapped. The agent stopped being a subscription you buy and became a layer inside the tools you already use.
The Editor Got the Agent First
Cline started life as Claude Dev and became the most installed AI coding agent in the VS Code marketplace in 2026, past 5 million installs, completely open source under Apache 2.0, backed by 61k+ GitHub stars (opensourcealternatives.to).
What makes it an agent instead of autocomplete is the Plan/Act split: it proposes a plan, you approve it, then it works with permissioned access to files, the terminal, the browser, and MCP tools. Its community fork Roo Code covers the same ground for people who wanted different defaults.
SideCar pushes the same idea harder.
It’s a free, self-hosted VS Code extension sold as “a drop-in replacement for GitHub Copilot and Claude Code,” with “full agentic capabilities, inline completions. And tool use” across local Ollama models, Anthropic, OpenAI, Fireworks, OpenRouter, Google Gemini, Groq, Kickstand, or any OpenAI-compatible server (VS Code Marketplace). The listing calls it “a full agent loop, not just chat,” which is the entire trend in six words.
The lighter-weight options round it out.
Continue is described as similar to Cursor but open source under Apache license. And Cody from Sourcegraph plugs into “VS Code, JetBrains, or others” (dev.to). Same editor, same keybindings, nothing new to learn.
My take: the permission model is the actual product. Closed tools ask you to trust a vendor’s defaults, and the good ones earn it. Open agents put the approval step in your hands, and that’s the difference between an assistant and a liability.
The Terminal Counterattack: OpenCode
The terminal scene has a clear front-runner this year. One guide states flatly that “OpenCode has become the dominant open-source coding agent in 2026” (dev.to). It’s built in Go by the SST team, runs as a terminal-native TUI, ships two built-in agents named Build and Plan, integrates LSP for real code intelligence. And keeps persistent project context in an AGENTS.md file (daily.dev). Star counts disagree because it’s climbing fast: 162k+ on one review, 161,000 on another (opensourcealternatives.to, daily.dev).
It supports 75+ LLM providers “including Claude, GPT, Gemini. And local Ollama models,” and it runs fully air-gapped via Ollama (daily.dev). There’s even a JetBrains plugin, OpenCode_UI, described as “a JetBrains IDE plugin that integrates OpenCode,” distributed through the JetBrains Marketplace (GitHub). The terminal agent is now moving into the IDEs too.
Aider is the veteran in this lane: an open source terminal agent built for developers who want “Claude Code-style capabilities without vendor lock-in,” and it stays Git-native while doing it (dev.to). The detail I’d underline is AGENTS.md. Project context that lives in your repository instead of a vendor’s cloud means the agent’s brain travels with the code. And you keep it when you fork.
Fully Local: OpenHands Plus Ollama
OpenHands, formerly OpenDevin, gets described in one technical write-up as “a full-fledged autonomous software engineer” that touches the terminal, reads files, writes unit tests. And iterates inside an isolated Docker sandbox (webdesigner.la). The same write-up calls it “the developer command center”: it breaks goals into atomic tasks, runs bash, navigates the filesystem, evaluates errors. And commits straight into Git.
Pair it with Ollama and the model runs on your box.
Ollama exposes an OpenAI-compatible REST API on port 11434, runs quantized GGUF models, and offloads to your GPU. The stack’s pitch is “100% data sovereignty, zero token bills. And infinite execution headroom on your own hardware,” and I’d take that pitch with salt. Zero token bills is true. Equal output quality is not part of the claim, and neither is your electricity bill. What you actually buy is the sandbox and the data boundary. And for client code that boundary is worth real money.
Fireship recently ran through five free open-source tools aimed at exactly this cost problem: Ollama, 9router, Headroom, Diffy, and OpenHands (ai-tldr.dev). OpenHands earned the description “an open coding agent you can point at whichever backend you chose,” and that’s the pattern across every tool in this post. The agent is open. Backend: your call.
What This Means If You Run a Small Shop
I run a one-person automation agency, so I read this shift through the invoice. Three things matter more than star counts:
– Cost control. Cline is free to start with your own API key, and rankings slot it under “control and cost transparency.” You set the caps instead of a vendor setting them for you.
– Client data. The OpenHands plus Ollama path keeps source code off vendor servers, with the Docker sandbox as the fence between the agent and your machine. That’s a conversation you want to have before a client asks.
– Portability. A curated open-source collection of 864+ reusable agentic skills works across “Claude Code, Gemini CLI, Codex CLI, Cursor, GitHub Copilot, and others” (daily.dev). The skill layer moves even when the tool doesn’t, which softens lock-in everywhere.
If you build your own tooling instead of installing someone else’s, the parts are open too. SWE-Kit is “a headless IDE with features like LSPs, Code Indexing, and Code RAG” (dev.to). The internals of an IDE are now components you can wire into your own agent.
The boring read on this trend is that open source wins on price. The real story is that the agent loop moved into tools you control, with permission prompts you can see and licenses you can read. Price is the side effect.
What to Actually Do This Week
Pick one editor agent and one terminal agent, both free. Install Cline in VS Code and OpenCode in your terminal, then run them on a scratch repo before you point them at anything a client pays for. If you handle code you can’t ship to a vendor, set up OpenHands with Ollama on one low-stakes internal project and measure what local models cost you in review time. Then compare that number to your current AI bill. That comparison, not the GitHub stars, tells you which side of this shift your shop is on.
