hexiel

An open-source AI coding agent for your terminal and browser — a guardian angel for your codebase.
Runs on local models (Ollama, even on a mini-PC iGPU) or any big cloud model.
A free, self-hostable alternative to Claude Code and opencode.

🌐 Website: hexiel.tech · designed by JKagiDesigns LLC

Why hexiel

• Built for modest hardware. Everything that doesn't need a model (searching, mapping the project, waiting on tests, distilling web pages, batching work in a python script) runs locally in Python. The prompt is kept lean: on an Intel iGPU mini-PC running qwen3.6:35b-a3b-coding, each request's prompt processing dropped from 46.5 s to 23.7 s in v0.2.6.
• Any model, local or cloud. Ollama (local or Cloud), Anthropic, OpenAI, Gemini, xAI, OpenRouter, DeepSeek, or any OpenAI-compatible server (vLLM, LM Studio, TGI). Switch per session or permanently, from the UI.
• Terminal and browser. A full-screen TUI, a browser UI, one-shot headless runs, and an OpenAI-compatible API — one agent core behind all of them.
• Brings your ecosystem. Your existing Claude Code skills (~/.claude/skills) and OpenWebUI tool/pipe/filter plugins work as-is.
• Remembers and keeps track. File-based memory (MEMORY.md), a todo.md that survives crashes, auto-compaction at a Claude-Code-sized context window.
• Fixes itself. Crashes become incident files; /heal reproduces, fixes, tests and proposes a merge request — you approve it.
• Free to use, can't be resold. GPLv3 + Commons Clause.

Quickstart

The quickest way, from PyPI:

pipx install 'hexiel[serve]'          # or: pip install 'hexiel[serve]'
hexiel --doctor                       # preflight checks with copy-paste fixes
cd ~/code/your-project && hexiel

Or from source (to hack on it):

git clone https://gitlab.com/jkagidesigns1/public/applications/hexiel.git
cd hexiel
python -m venv .venv
.venv/bin/pip install -e '.[serve]'     # Windows: .venv\Scripts\pip install -e ".[serve]"
.venv/bin/hexiel --doctor               # preflight checks with copy-paste fixes
.venv/bin/hexiel                        # start the TUI

Then put it on your PATH so it runs from any project:

ln -s "$PWD/.venv/bin/hexiel" ~/.local/bin/hexiel
cd ~/code/your-project && hexiel

hexiel always treats the directory you launch it from as the project: it detects that tree's toolchain, reads its skills and keeps its state (.hexiel/ — todo, memory, incidents, web cache) right there. The header shows the hexiel version and the project you're in; hexiel -c resumes the last conversation of this project.

Windows: works out of the box — the agent shells through PowerShell (pwsh, winget install Microsoft.PowerShell), and bash falls back to it when no WSL/git-bash is on PATH.

Ways to run it

hexiel                    # full-screen terminal UI
hexiel --serve            # browser UI at http://127.0.0.1:8777
hexiel -p "explain this repo in one paragraph"   # one-shot, headless
hexiel -c                 # resume this project's last conversation
hexiel -m sonnet          # pick a model profile for this run

Using it

Type / for the command menu — every command and skill with what it does; ↑/↓, Tab to complete, Enter to run. /model lists your profiles.	/config shows every setting in a table. Pick a row, pick a value, then choose this session or save permanently (one line of config.toml changes; comments are kept).

• Screenshots: type an image path in your message (why does @shot.png look broken?, ~/Pictures/error.jpg) and it's attached for vision models.
• Activity line: while hexiel works, the bottom-left shows what it's doing — thinking, writing, running your tests — with elapsed time and tokens. Ctrl+C stops a turn.
• Approvals: edits and commands ask first (y / always / n); /auto goes hands-free.
• Updates: hexiel checks for new releases in the background. /update (or the web UI's update button) installs it and restarts, resuming your conversation. It refuses to update a checkout with uncommitted changes.

Control, safety and flow

For analysts, researchers and small businesses

No code needed — just ask:

Data and scheduling tools load only when needed (automatically when a project contains data files, or on request), so coding sessions don't pay for them in every prompt.

Browser UI

hexiel --serve runs the same agent in a browser (with the same / command menu and live model picker): streamed markdown, tool-call cards, approval dialogs, model picker, ⚙ settings, context gauge, todo, memory and sessions. Local-only by default; --host 0.0.0.0 prints a loud warning (anyone who can reach the port can run commands on your machine).

Models

Fastest start: /model add <preset> in the terminal UI — presets for Claude (sonnet, opus, haiku), OpenAI (gpt), Gemini (gemini), xAI (grok), DeepSeek, Kimi, GLM, Mistral, Groq, Together, Fireworks, OpenRouter, Azure, Bedrock, and local Ollama / LM Studio / vLLM / llama.cpp. hexiel --presets lists them; docs/MODELS.md has copy-paste config for each, including provider quirks hexiel handles for you.

Profiles live in ~/.config/hexiel/config.toml (written on first run). Switch with /model NAME, hexiel -m NAME, or the settings table.

default = "local"

[models.local]                      # Ollama on this machine or a home server
provider = "openai"
base_url = "http://localhost:11434/v1"
model = "qwen3.6:35b-a3b-coding"    # coding + screenshots + tool calling in one model
context_window = 65536              # match the server's OLLAMA_CONTEXT_LENGTH
extra_body = { reasoning_effort = "none" }   # skip slow "thinking" on modest hardware

[models.sonnet]
provider = "anthropic"
model = "claude-sonnet-5-5"
api_key_env = "ANTHROPIC_API_KEY"

Picking a local model: on low-end hardware, prefer mixture-of-experts models with ~3B active parameters (they run several times faster than dense models of the same size) that have vision + tool-calling. qwen3.6:35b-a3b-coding passed all of hexiel's checks (tool calls, screenshots, a compiled Java task) on an Intel iGPU at ~12 tokens/s. Hybrid "thinking" models should run with reasoning_effort = "none"; otherwise one step can take minutes.

What hexiel does

Tools

bash · python (batch many steps into one local script) · read · write · edit · glob · grep · list · map (cached project tree) · file_info · powershell · test (your detected runner) · container (docker/podman + compose) · view_image / image_edit · web_search / web_fetch (no API key needed) · memory · todo · gitlab_mr · skill — plus any MCP server's tools and any OpenWebUI plugin in plugins/.

Context discipline

• Auto-compaction, Claude-Code style: at 82% of the context window, older history is summarized (task, recent work, decisions, errors, next steps) and the conversation continues. Real provider usage numbers drive it.
• Local-first token economy: tool output is budgeted and distilled in Python before the model sees it.

Project instructions, todo and memory — maintained automatically

• Project instructions: AGENTS.md / CLAUDE.md / HEXIEL.md (any letter case) at the project root are loaded into every session; a root todo.md is pointed out so the model reads it when you say "continue".
• todo.md: multi-step work is tracked in <project>/.hexiel/todo.md (- [ ] queued, one - [~] in progress, - [x] done). When a request takes three or more tool calls and the model hasn't planned it itself, hexiel logs it as a task, refreshes the where we left off line after every step and ticks it off when the turn completes — in Python, at zero token cost. If hexiel or your laptop dies mid-task, hexiel -c resumes from an accurate checkpoint.
• Memory: ~/.local/share/hexiel/memory/ (global) and <project>/.hexiel/memory/ (project), markdown notes indexed by MEMORY.md. The model saves what it learns; and every auto-compaction also extracts durable facts (build/test commands, conventions, your preferences) into auto-facts.md — deduplicated, no extra model call.
• Skills are SKILL.md folders from ~/.local/share/hexiel/skills/, the project, and ~/.claude/skills/ — Claude Code skills work unchanged.

Self-healing — fix hexiel, then share the fix with everyone

Crashes and provider errors are recorded to .hexiel/incidents/. Run /heal (or /heal <what went wrong> for a bug you noticed) and hexiel:

1. makes an isolated copy of its own source at the version you're running (a git worktree — or, for pip installs, a clone of the release tag) under ~/.local/share/hexiel/heal/. Your project and your install are untouched;
2. reproduces the bug, fixes the root cause and adds a test, running the suite there;
3. opens a lazygit-style review: changed files on the left with checkboxes, a colour diff on the right (space include/exclude, a all/none);
4. you choose:
   • Send to hexiel (and keep) — commits only the files you ticked and opens a merge request to the official repo (via a fork if you're not a maintainer), so every hexiel user gets the fix once it's reviewed. Needs a free GitLab account (/setup-gitlab <token>).
   • Keep just for me — applies the ticked files to your hexiel.
   • Discard, or decide later with /heal review.

MCP servers

hexiel runs Model Context Protocol servers — local (stdio) and remote (streamable HTTP). It reads Claude Code's .mcp.json from your project (and ~/.config/hexiel/mcp.json), so existing setups just work:

{ "mcpServers": {
    "files":  { "command": "npx", "args": ["-y", "@modelcontextprotocol/server-filesystem", "."] },
    "remote": { "type": "http", "url": "https://example.com/mcp",
                "headers": { "Authorization": "Bearer ${MY_TOKEN}" } } } }

or in config.toml, with an optional allowlist to keep prompts small on modest hardware:

[mcp.servers.files]
command = "npx"
args = ["-y", "@modelcontextprotocol/server-filesystem", "."]
tools = ["read_file", "list_directory"]     # expose only these

Tools appear as mcp__<server>__<tool>; read-only tools skip the approval prompt. /mcp shows each server's status, tool count and schema-token cost.

GitLab merge requests for your own projects (/ship, gitlab_mr)

• Owner flow: turn uncommitted work into a merge request (branch → commit → push → MR), approving each step.
• Contributor flow: hexiel forks the repo, pushes to your fork and opens an MR upstream — attributed to you.
• Auth via HEXIEL_GITLAB_TOKEN / GITLAB_TOKEN or /setup-gitlab <token>. gitlab.com and self-hosted.

OpenWebUI compatibility

1. Use hexiel from OpenWebUI (or any OpenAI client): point a connection at http://127.0.0.1:8777/v1/chat/completions. Read-only tools stay available; write tools are disabled over the API.
2. Use OpenWebUI plugins in hexiel: drop Tools / Pipe / Filter plugin files into plugins/ — methods become tools, Valves are honored.

Contributing

Fork → branch → merge request; the maintainer reviews and approves. hexiel can do the whole flow for you (/ship). See CONTRIBUTING.md.

.venv/bin/pytest                    # 117 tests: tools, providers, compaction, TUI, MCP,
                                    # self-heal, settings, updater, web UI, plugins
.venv/bin/python scripts/screenshots.py   # regenerate these screenshots

License

GPLv3 with the Commons Clause: free to use, study, fork and contribute — not free to sell as a product or service.