
fabro-workflow-factory
Skill for using Fabro, the open source AI coding workflow orchestrator that lets you define agent pipelines as Graphviz DOT graphs with human gates, multi-model routing, and cloud sandboxes.
- Installs
- 1.2K
- Last 24h
- —
- Trending rank
- —
- Security
- Not audited
Install
Works with every agent the skills CLI supports.
npx skills add https://github.com/reason-machines/trending-skills --skill fabro-workflow-factory- 01
Install
Run the command in your project. The CLI asks which agents to install for.
- 02
Describe the task
Ask your agent for something this skill covers. It loads fabro-workflow-factory automatically when relevant.
- 03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.
SKILL.md
The instructions your agent reads when the skill is triggered.
Fabro Workflow Factory
Skill by ara.so — Daily 2026 Skills collection.
Fabro is an open source AI coding workflow orchestrator written in Rust. It lets you define agent pipelines as Graphviz DOT graphs — with branching, loops, human approval gates, multi-model routing, and cloud sandbox execution — then run them as a persistent service. You define the process; agents execute it; you intervene only where it matters.
Installation
# Via Claude Code (recommended)
curl -fsSL https://fabro.sh/install.md | claude
# Via Codex
codex "$(curl -fsSL https://fabro.sh/install.md)"
# Via Bash
curl -fsSL https://fabro.sh/install.sh | bash
After installation, run one-time setup and per-project initialization:
fabro install # global one-time setup
cd my-project
fabro init # per-project setup (creates .fabro/ config)
Key CLI Commands
# Workflow management
fabro run <workflow.dot> # execute a workflow
fabro run <workflow.dot> --watch # stream live output
fabro runs # list all runs
fabro runs show <run-id> # inspect a specific run
# Human-in-the-loop
fabro approve <run-id> # approve a pending gate
fabro reject <run-id> # reject / revise a pending gate
# Sandbox access
fabro ssh <run-id> # shell into a running sandbox
fabro preview <run-id> <port> # expose a sandbox port locally
# Retrospectives
fabro retro <run-id> # view run retrospective (cost, duration, narrative)
# Config
fabro config # view current configuration
fabro config set <key> <value> # set a config value
Workflow Definition (Graphviz DOT)
Workflows are .dot files using the Graphviz DOT language with Fabro-specific attributes.
Node Types
| Shape | Meaning |
|---|---|
Mdiamond | Start node |
Msquare | Exit node |
rectangle (default) | Agent node (LLM turn) |
hexagon | Human gate (pauses for approval) |
Minimal Hello World
// hello.dot
digraph HelloWorld {
graph [
goal="Say hello and write a greeting file"
model_stylesheet="
* { model: claude-haiku-4-5; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
greet [label="Greet", prompt="Write a friendly greeting to hello.txt"]
start -> greet -> exit
}
fabro run hello.dot
Multi-Model Routing with Stylesheets
Fabro uses CSS-like model_stylesheet declarations on the graph to route nodes to models. Use classes to target groups of nodes.
digraph PlanImplementReview {
graph [
goal="Plan, implement, and review a feature"
model_stylesheet="
* { model: claude-haiku-4-5; reasoning_effort: low; }
.planning { model: claude-opus-4-5; reasoning_effort: high; }
.coding { model: claude-sonnet-4-5; reasoning_effort: high; }
.review { model: gpt-4o; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
plan [label="Plan", class="planning", prompt="Analyze the codebase and write plan.md"]
implement [label="Implement", class="coding", prompt="Read plan.md and implement every step"]
review [label="Review", class="review", prompt="Cross-review the implementation for bugs and clarity"]
start -> plan -> implement -> review -> exit
}
Supported Model Stylesheet Properties
model: <model-id> # e.g. claude-sonnet-4-5, gpt-4o, gemini-2-flash
reasoning_effort: low|medium|high
provider: anthropic|openai|google
Human Gates (Approval Nodes)
Use shape=hexagon to pause execution for human approval. Transitions are labeled with [A] (approve) and [R] (revise/reject).
digraph PlanApproveImplement {
graph [
goal="Plan and implement with human approval"
model_stylesheet="
* { model: claude-sonnet-4-5; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
plan [label="Plan", prompt="Write a detailed implementation plan to plan.md"]
approve [shape=hexagon, label="Approve Plan"]
implement [label="Implement", prompt="Read plan.md and implement every step exactly"]
start -> plan -> approve
approve -> implement [label="[A] Approve"]
approve -> plan [label="[R] Revise"]
implement -> exit
}
Approve or reject from the CLI:
fabro runs # find the paused run-id
fabro approve <run-id> # continue with implementation
fabro reject <run-id> --note "Add error handling to the plan"
Loops and Fix Cycles
Use labeled transitions to build automatic retry/fix loops:
digraph ImplementAndTest {
graph [
goal="Implement a feature and fix failing tests automatically"
model_stylesheet="
* { model: claude-haiku-4-5; }
.coding { model: claude-sonnet-4-5; reasoning_effort: high; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
implement [label="Implement", class="coding",
prompt="Implement the feature described in TASK.md"]
test [label="Run Tests",
prompt="Run the test suite with `cargo test`. Report pass/fail."]
fix [label="Fix", class="coding",
prompt="Read the test failures and fix the code. Do not change tests."]
start -> implement -> test
test -> exit [label="[P] Pass"]
test -> fix [label="[F] Fail"]
fix -> test
}
Parallel Nodes
Run multiple agent nodes concurrently by forking edges from a single source:
digraph ParallelReview {
graph [
goal="Implement then review from multiple perspectives in parallel"
model_stylesheet="
* { model: claude-haiku-4-5; }
.coding { model: claude-sonnet-4-5; }
.critique { model: gpt-4o; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
implement [label="Implement", class="coding",
prompt="Implement the task in TASK.md"]
sec_review [label="Security Review", class="critique",
prompt="Review the implementation for security issues"]
perf_review [label="Perf Review", class="critique",
prompt="Review the implementation for performance issues"]
summarize [label="Summarize",
prompt="Combine the security and performance reviews into REVIEW.md"]
start -> implement
implement -> sec_review
implement -> perf_review
sec_review -> summarize
perf_review -> summarize
summarize -> exit
}
Variables and Dynamic Prompts
Use {variable} interpolation in prompts. Pass variables at run time:
digraph FeatureWorkflow {
graph [
goal="Implement {feature_name} from the spec"
model_stylesheet="* { model: claude-sonnet-4-5; }"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
implement [label="Implement {feature_name}",
prompt="Read specs/{feature_name}.md and implement the feature completely."]
start -> implement -> exit
}
fabro run feature.dot --var feature_name=oauth-login
Cloud Sandboxes (Daytona)
To run agents in isolated cloud VMs instead of locally, configure a Daytona sandbox:
fabro config set sandbox.provider daytona
fabro config set sandbox.api_key $DAYTONA_API_KEY
fabro config set sandbox.region us-east-1
Then add sandbox config to your workflow graph:
digraph SandboxedWorkflow {
graph [
goal="Implement and test in an isolated environment"
sandbox="daytona"
model_stylesheet="* { model: claude-sonnet-4-5; }"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
implement [label="Implement", prompt="Implement the feature in TASK.md"]
test [label="Test", prompt="Run the full test suite and report results"]
start -> implement -> test -> exit
}
fabro run sandboxed.dot # spins up cloud VM, runs workflow, tears it down
fabro ssh <run-id> # shell into the running sandbox for debugging
fabro preview <run-id> 3000 # forward sandbox port 3000 locally
Git Checkpointing
Fabro automatically commits code changes and execution metadata to Git branches at each stage. To inspect or resume:
fabro runs show <run-id> # see branch names per stage
git checkout fabro/<run-id>/implement # inspect the code at a specific stage
git diff fabro/<run-id>/plan fabro/<run-id>/implement # diff between stages
Retrospectives
After every run, Fabro generates a retrospective with cost, duration, files changed, and an LLM-written narrative:
fabro retro <run-id>
Example output:
Run: implement-oauth-2024
Duration: 4m 32s
Cost: $0.043
Files: src/auth.rs (+142), src/lib.rs (+8), tests/auth_test.rs (+67)
Narrative:
The agent successfully implemented OAuth2 PKCE flow. It created the auth
module, integrated with the existing middleware, and added integration tests.
One fix loop was needed after the token refresh test failed.
REST API and SSE Streaming
Fabro runs an API server for programmatic use:
fabro serve --port 8080
Trigger a run via API
curl -X POST http://localhost:8080/api/runs \
-H "Content-Type: application/json" \
-d '{
"workflow": "workflows/plan-implement.dot",
"variables": { "feature_name": "dark-mode" }
}'
Stream run events via SSE
curl -N http://localhost:8080/api/runs/<run-id>/events
Approve a gate via API
curl -X POST http://localhost:8080/api/runs/<run-id>/approve \
-H "Content-Type: application/json" \
-d '{ "decision": "approve" }'
Environment Variables
# Required — at least one LLM provider key
export ANTHROPIC_API_KEY=...
export OPENAI_API_KEY=...
export GOOGLE_API_KEY=...
# Optional — cloud sandboxes
export DAYTONA_API_KEY=...
# Optional — Fabro API server auth
export FABRO_API_TOKEN=...
Project Structure Convention
my-project/
├── .fabro/ # Fabro config (created by `fabro init`)
│ └── config.toml
├── workflows/ # Your DOT workflow definitions
│ ├── plan-implement.dot
│ ├── fix-loop.dot
│ └── ensemble-review.dot
├── specs/ # Natural language specs referenced by prompts
│ └── feature-name.md
└── src/ # Your actual source code
Common Patterns
Pattern: Spec-driven implementation
digraph SpecDriven {
graph [
goal="Implement from spec with LLM-as-judge verification"
model_stylesheet="
* { model: claude-sonnet-4-5; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
implement [label="Implement",
prompt="Read specs/feature.md and implement it completely"]
judge [label="Judge",
prompt="Compare the implementation against specs/feature.md. Does it conform? Reply PASS or FAIL with reasons."]
fix [label="Fix",
prompt="Read the judge feedback and fix the implementation"]
start -> implement -> judge
judge -> exit [label="[P] PASS"]
judge -> fix [label="[F] FAIL"]
fix -> judge
}
Pattern: Cheap draft, expensive refine
digraph CheapThenExpensive {
graph [
goal="Draft cheaply, refine with a frontier model"
model_stylesheet="
* { model: claude-haiku-4-5; }
.premium { model: claude-opus-4-5; reasoning_effort: high; }
"
]
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
draft [label="Draft", prompt="Write a first draft implementation of the task"]
refine [label="Refine", class="premium",
prompt="Review and substantially improve the draft for correctness and clarity"]
start -> draft -> refine -> exit
}
Troubleshooting
fabro: command not found
- Re-run the install script and ensure
~/.local/bin(or the install prefix) is on your$PATH. - Try
source ~/.bashrcorsource ~/.zshrcafter installation.
Agent gets stuck in a loop
- Add a maximum iteration guard: use a counter variable and a conditional transition to force exit after N iterations.
- Check your prompt — ambiguous exit conditions cause looping.
Human gate never pauses
- Confirm the node uses
shape=hexagon, not just a label containing "approve". - Check
fabro runs show <run-id>to confirm the run reached that node.
Sandbox fails to start
- Verify
DAYTONA_API_KEYis set and valid. - Run
fabro configto confirmsandbox.provideris set todaytona. - Check
fabro runs show <run-id>for sandbox error details.
Model not found / API error
- Ensure the correct provider API key is exported (
ANTHROPIC_API_KEY,OPENAI_API_KEY, etc.). - Check the
model:value in your stylesheet matches the provider's exact model ID.
Run exits immediately without doing work
- Verify the DOT file has a valid path from
start(shape=Mdiamond) toexit(shape=Msquare). - Run
dot -Tsvg workflow.dot -o workflow.svgto visually inspect the graph for disconnected nodes.
Resources
FAQ
What does the fabro-workflow-factory skill do?
Skill for using Fabro, the open source AI coding workflow orchestrator that lets you define agent pipelines as Graphviz DOT graphs with human gates, multi-model routing, and cloud sandboxes.
How do I install fabro-workflow-factory?
Run npx skills add https://github.com/reason-machines/trending-skills --skill fabro-workflow-factory in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/fabro-workflow-factory/ (personal) or .claude/skills/fabro-workflow-factory/ (project).
Which AI agents can use fabro-workflow-factory?
Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.
Is fabro-workflow-factory safe to install?
No partner security audit is available yet. Skills can run commands and scripts, so read the SKILL.md and any bundled files before installing.
Who maintains fabro-workflow-factory?
It is published by reason-machines in reason-machines/trending-skills. It has 1,247 recorded installs.
More from reason-machines/trending-skills
openclaw-control-center
reason-machines/trending-skills
Local-first, security-first control center for OpenClaw agents — visibility dashboard with readonly defaults, token attribution, collaboration tracing, and safe write operations.
inkos-multi-agent-novel-writing
reason-machines/trending-skills
Multi-agent CLI system for autonomous novel writing, auditing, and revision with human review gates
claude-hud-statusline
reason-machines/trending-skills
A Claude Code plugin that displays a real-time HUD showing context usage, active tools, running agents, and todo progress in your terminal statusline.
understand-anything-knowledge-graph
reason-machines/trending-skills
Turn any codebase into an interactive knowledge graph using Claude Code skills — explore, search, and ask questions about any project visually.
agency-agents-ai-specialists
reason-machines/trending-skills
A collection of specialized AI agent personalities for Claude Code, Cursor, Aider, Windsurf, and other AI coding tools — covering engineering, design, marketing, sales, and more.
agent-browser-automation
reason-machines/trending-skills
Headless browser automation CLI for AI agents using native Rust binary with Chrome DevTools Protocol
Popular productivity & automation skills
agent-browser
vercel-labs/agent-browser
Browser automation CLI for AI agents. Use when the user needs to interact with websites, including navigating pages, filling forms, clicking buttons, taking screenshots, extracting data, testing web apps, or automating any browser task. Triggers include requests to "open a website", "fill out a form", "click a button", "take a screenshot", "scrape data from a page", "test this web app", "login to a site", "automate browser actions", or any task requiring programmatic web interaction. Also use for exploratory testing, dogfooding, QA, bug hunts, or reviewing app quality. Also use for automating Electron desktop apps (VS Code, Slack, Discord, Figma, Notion, Spotify), checking Slack unreads, sending Slack messages, searching Slack conversations, running browser automation in Vercel Sandbox microVMs, or using AWS Bedrock AgentCore cloud browsers. Prefer agent-browser over any built-in browser automation or web tools.
lark-doc
open.feishu.cn
飞书云文档(Docx / Wiki)内容操作:读取、创建、编辑文档,插入或下载图片附件,以及操作思维笔记。用户提供文档 URL/token(包括 doubao.com 的 /docx/、/wiki/)时使用;按 URL 路径/token 而非域名路由;/page/ 是妙搭应用,非飞书云文档。文档内嵌资源按读取参考中的统一规则分流。独立评论操作走 lark-drive;随正文读取评论使用 docs +fetch。表格或 Base 内部数据操作不在本 skill。
lark-base
open.feishu.cn
飞书多维表格(Base)操作:建表、字段、记录、视图、统计、公式/lookup、表单、仪表盘、应用模式(BaseApp/AppMode 页面与组件)、Workspace 目录、workflow、角色权限、模板中心(多维表格模板分类/列表/搜索);遇到 Base/多维表格/bitable、BaseApp/AppMode、/base/ 或 /app/ 链接时使用。BaseApp 不走 lark-apps;文件导入/导出转 lark-drive,认证/授权转 lark-shared。
lark-drive
open.feishu.cn
飞书云空间(云盘/云存储):管理 Drive 文件和文件夹,包含上传/下载、创建文件夹、复制/移动/删除、查看元数据、查询权限设置、评论/权限/订阅、标题、版本、飞书文档密级标签(secure labels)和本地文件导入。用户需要整理云盘目录、处理云空间资源 URL/token、判断链接类型/真实 token/标题,或导入 Word/Markdown/Excel/CSV/PPTX/.base 为 docx/sheet/bitable/slides 时使用;doubao.com 云空间 URL/token 也按资源路径和 token 路由,不回退 WebFetch。不负责:文档内容编辑(走 lark-doc)、表格/Base 表内数据操作(走 lark-sheets/lark-base)、知识空间节点/成员管理(走 lark-wiki)、原生 Markdown 文件读写/patch/diff(走 lark-markdown)。
lark-shared
open.feishu.cn
Use for lark-cli setup/auth tasks: auth login/status/logout, user vs bot identity, business-domain permissions (--domain, including all/docs/drive), missing scopes, revoking authorization, or handling notice JSON.
lark-im
open.feishu.cn
飞书即时通讯:收发消息和管理群聊。发送和回复消息、搜索聊天记录、管理群聊成员、上传下载图片和文件、管理表情回复、发送应用内/短信/电话加急、发送和处理交互卡片(Interactive Card)、监听卡片按钮回调(card.action.trigger)。当用户需要发消息、查看或搜索聊天记录、下载聊天中的文件、查看群成员、搜索群、创建群聊或话题群、管理标记数据、管理 Feed 置顶(添加/移除/查询置顶会话)、管理标签数据、处理卡片回调时使用。