Rank #09 · Daily · DevTools
thinkrail: JetBrains' Lightweight Vibe-Coding IDE Around pi Agents
A real (but lightweight) IDE that isolates each agent task in a git worktree and keeps project intent in living specs — built around pi.
What it does
ThinkRail is a JetBrains incubator project: an agentic IDE whose engine is the open pi coding agent. From the README:
- Isolated workspaces. Open a git repo as a project; cut workspaces as
git worktrees so agents work in parallel without touching your main checkout. Finished workspaces settle onto a shelf; the topbar tracks branch vs origin and PR / CI state. - A real workbench. Splittable Monaco editor tabs, Files tree with live git marks, terminals, and documents — all scoped to the active workspace. Anchored review comments on diffs can be sent into chat as structured context.
- Concurrent
pichats per workspace, each with its own model and live token/cost readout; steer a running turn, queue follow-ups, share an editable plan, delegate to subagents. - Living specs. A graph of
SPEC.mdfiles beside the code; the agent maintains it through dedicatedspec_*tools. Specs render as a tree in the workbench. - Skills, MCP, extensions. Reads portable Agent Skills in place; connects MCP servers from
pi'smcp.jsonwith approval for non-read-only tools; Settings → Extensions toggles ThinkRail andpipackages. - Your providers. JetBrains AI sign-in, or any provider through
pi's auth — including custom OpenAI-compatible servers (LiteLLM, vLLM, Ollama, LM Studio, llama.cpp). ThinkRail has no accounts of its own. - Ships as a native desktop app or
thinkrailCLI that opens the same UI in the browser. Homepage: thinkrail.ai.
Who it's for
Developers who want a spec-driven, worktree-isolated agent IDE rather than a thin chat pane, especially people already using (or willing to adopt) the pi agent. Also useful if you want JetBrains-adjacent tooling without migrating your LLM credentials into a closed IDE account.
Stars / language / license
7,414 stars · TypeScript · Apache-2.0
Data verified: 2026-11-04 09:13 Asia/Shanghai (GitHub API get_repository + README get_file_contents)
Trending note: +3,898/wk (weekly Trending filler; selection captured 09:12 Asia/Shanghai)
Category tags
DevTools · agent-IDE · vibe-coding · pi-agent · worktrees · spec-driven · JetBrains
How it differs from similar projects
Compared with Cursor. Cursor is a mature commercial IDE with its own agent stack. ThinkRail is open Apache-2.0, thin around pi, and centers worktree isolation + living specs.
Compared with T3 Code (#08). T3 Code is a multi-provider control surface for CLIs you already run. ThinkRail is a full lightweight IDE whose primary agent is pi, with deeper editor / spec / workspace integration.
Compared with bare pi in a terminal. Same agent engine; ThinkRail adds the workbench, worktrees, specs UI, MCP approval UX, and desktop packaging.
TidyHow hasn't measured coding-task success rates against Cursor or other agent IDEs — treat differences as product-architecture contrasts, not scores.