Open-source AI agent platform for agentic coding — MCP server, knowledge packs, and AI workflow automation.

sidebutton.com · docs.sidebutton.com
Run AI coding agents with agentic workflows, knowledge packs, and real browser control. Connect Claude Code, Codex, Cursor, ChatGPT, or any MCP client.
What you get
| |
|---|
| MCP Server | AI agent tools for browser control, workflow execution, and knowledge pack access. Stdio and SSE transports. |
| REST API | Trigger workflows remotely from webhooks, cron jobs, mobile apps, or other agents. |
| Workflow Engine | AI workflow automation with browser, git, issue-tracking, LLM, shell, and control-flow steps. Define agentic workflows in YAML. |
| Knowledge Packs | Installable domain knowledge — CSS selectors, data models, state machines. Role playbooks turn coding agents into an AI software engineer, QA, or PM. |
| Chrome Extension | Browser commands with real DOM access via WebSocket, not screenshots. Recording mode. |
| Dashboard | Svelte UI — workflow browser, run logs, skill pack manager, system status. |
Quick Start
npx sidebutton@latest
pnpm install && pnpm build && pnpm start
CLI
pnpm cli serve
pnpm cli serve --stdio
pnpm cli list
pnpm cli status
pnpm cli registry add <path|url>
pnpm cli registry update [name]
pnpm cli registry remove <name>
pnpm cli search [query]
pnpm cli init [domain]
pnpm cli validate [path]
pnpm cli publish [source]
MCP Server
SideButton is an open-source MCP server for AI coding agents. Agents connect to it directly for browser control, workflow automation, and domain knowledge.
Works with Claude Code, Codex, Cursor, Claude Desktop, VS Code, Windsurf, ChatGPT — any MCP client.
Claude Code
claude mcp add sidebutton --transport http http://localhost:9876/mcp
Persists to ~/.claude.json; add --scope project to write ./.mcp.json instead. Full guide: Claude Code SideButton MCP setup.
Codex
Add to ~/.codex/config.toml:
[mcp_servers.sidebutton]
command = "sidebutton"
args = ["serve", "--stdio"]
Full guide: OpenAI Codex SideButton MCP setup.
Claude Desktop
Add to ~/Library/Application Support/Claude/claude_desktop_config.json:
{
"mcpServers": {
"sidebutton": {
"command": "npx",
"args": ["sidebutton", "--stdio"]
}
}
}
Cursor
Add to ~/.cursor/mcp.json:
{
"mcpServers": {
"sidebutton": {
"url": "http://localhost:9876/mcp"
}
}
}
| Tool | Description |
|---|
run_workflow | Execute a workflow by ID |
get_run_log | Get execution log for a run |
list_workflows | List all available workflows |
get_workflow | Get workflow YAML definition |
list_run_logs | List recent workflow executions |
publish_artifact | Publish evidence (screenshots, reports) from a session |
get_browser_status | Check browser extension connection |
capture_page | Capture selectors from current page |
navigate | Navigate browser to URL |
snapshot | Get page accessibility snapshot |
click | Click an element |
type | Type text into an element |
press_key | Send keyboard keys |
scroll | Scroll the page |
extract | Extract text from element |
screenshot | Capture page screenshot (pass path to write a PNG file instead of returning image bytes) |
select_option | Select dropdown option |
fill | Fill input value (React-compatible) |
wait | Wait for element or delay |
exists | Check if element exists |
extract_all | Extract all matching elements |
extract_map | Extract structured data from repeated elements |
scroll_into_view | Scroll element into viewport |
hover | Hover over element |
inject_css | Inject CSS into the page (blur/hide elements before a screenshot) |
evaluate | Execute JavaScript in browser |
browser_batch | Run a sequence of browser actions in one call |
set_basic_auth | Set HTTP Basic Auth credentials for the connected tab |
clear_basic_auth | Clear stored HTTP Basic Auth credentials |
REST API
JSON endpoints for external integrations. The same workflows are available via MCP locally and via REST remotely.
curl -X POST http://localhost:9876/api/workflows/check_ticket/run \
-H "Content-Type: application/json" \
-d '{"params": {"ticket_id": "PROJ-123"}}'
curl http://localhost:9876/api/workflows
curl http://localhost:9876/api/runs/latest
Trigger workflows from webhooks, cron jobs, mobile apps, or other agents on different machines.
Workflow Engine
YAML-first orchestration for agentic workflows. Step types by family:
Step Types
| Family | Steps |
|---|
browser.* | navigate, click, type, fill, extract, extractAll, extractMap, snapshot, screenshot, wait, exists, hover, key, scroll, scrollIntoView, select_option, injectCSS, injectJS |
git.* | createPR, getPR, listPRs, getIssue, listIssues |
issues.* | create, get, search, comment, attach, transition |
llm.* | classify, decide, generate |
control.* | if, foreach, retry, stop |
shell / terminal | shell.run, terminal.open, terminal.run |
data.* | first, get |
workflow.call | Call another workflow with parameters |
LLM steps work with Ollama (local), OpenAI, and Anthropic.
Example
id: check_ticket_status
title: "Check Jira ticket and classify"
steps:
- type: browser.navigate
url: "https://your-org.atlassian.net/browse/{{ticket_id}}"
- type: browser.extract
selector: "[data-testid='status-field']"
as: current_status
- type: control.if
condition: "{{current_status}} != 'Done'"
then:
- type: llm.classify
prompt: "Should this ticket be closed? Context: {{current_status}}"
classes: [close, keep_open]
as: decision
Variable Interpolation
Use {{variable}} syntax to reference extracted values or parameters:
steps:
- type: browser.extract
selector: ".username"
as: user
- type: shell.run
cmd: "echo 'Hello, {{user}}!'"
Knowledge Packs
Installable domain knowledge (skill packs) per web app or domain. Knowledge packs power AI code review, automated testing, and enterprise AI agent deployments.
Also referred to as skill packs in code and CLI commands.
- Selectors — CSS selectors for UI elements
- Data models — entity types, fields, relationships, valid states
- State machines — valid transitions per state
- Role playbooks — role-specific procedures (QA, SE, PM, SD)
- Common tasks — step-by-step procedures, gotchas, edge cases
sidebutton install github.com
sidebutton install atlassian.net
Open registry with published packs for popular web apps. Build and share packs for any domain.
Chrome Extension
Install the SideButton Chrome Extension from the Chrome Web Store.
- Browser commands — navigate, click, type, extract, scroll, wait, snapshot
- Real DOM access via CSS selectors — not pixel coordinates, not screenshots
- Recording mode — capture manual actions as workflows
- Embed buttons — inject action buttons into any web page
- WebSocket connection — stable reconnection, works with local or remote server
After installing:
- Navigate to any website
- Click the SideButton extension icon
- Click "Connect This Tab"
Dashboard & Observability
Svelte UI at http://localhost:9876:
- Workflow browser — list, search, run
- Run logs — step-by-step execution traces with timing, variables, errors
- Skill pack manager — install, browse, inspect
- System status — extension connection, LLM config, server health
SideButton handles multi-agent orchestration — from workflow execution to knowledge injection.
Architecture
┌──────────────────────────────────────────────────────────────────────────┐
│ @sidebutton/server │
│ │
│ ┌─────────────────────┐ ┌──────────────────────────────────────────┐ │
│ │ stdio Transport │ │ Fastify HTTP + WebSocket (port 9876) │ │
│ │ ───────────────── │ │ ──────────────────────────────────── │ │
│ │ stdin → JSON-RPC │ │ GET / → Dashboard (Svelte) │ │
│ │ stdout ← JSON-RPC │ │ GET /ws → Chrome Extension WS │ │
│ │ (Claude Desktop) │ │ POST /mcp → MCP JSON-RPC (SSE) │ │
│ └──────────┬──────────┘ │ GET /api/* → REST API │ │
│ │ └──────────────────────┬───────────────────┘ │
│ │ │ │
│ └──────────────────┬──────────────────┘ │
│ ▼ │
│ ┌────────────────────────────────────────────────────────────────────┐ │
│ │ @sidebutton/core │ │
│ │ │ │
│ │ - Workflow types & parser (YAML) │ │
│ │ - Step executors (YAML step types) │ │
│ │ - Variable interpolation │ │
│ │ - Execution context & events │ │
│ └────────────────────────────────────────────────────────────────────┘ │
└──────────────────────────────────────────────────────────────────────────┘
▲ ▲ ▲ ▲
│ stdio │ WebSocket │ HTTP POST │ REST
▼ ▼ ▼ ▼
┌──────────────┐ ┌─────────────────┐ ┌─────────────────┐ ┌───────────────────┐
│Claude Desktop│ │ Chrome Extension│ │ Claude Code │ │ Mobile App │
│ (MCP stdio) │ │ (Browser Auto) │ │ (MCP SSE) │ │ (REST Client) │
└──────────────┘ └─────────────────┘ └─────────────────┘ └───────────────────┘
Project Structure
sidebutton/
├── packages/
│ ├── core/ # @sidebutton/core — workflow engine
│ │ └── src/
│ │ ├── types.ts # Workflow types
│ │ ├── parser.ts # YAML loader
│ │ ├── executor.ts # Workflow runner
│ │ └── steps/ # Step implementations
│ ├── server/ # @sidebutton/server — MCP + HTTP + CLI
│ │ ├── bin/ # CLI entry point
│ │ └── src/
│ │ ├── server.ts # Fastify HTTP server
│ │ ├── stdio-mode.ts # stdio transport entry point
│ │ ├── extension.ts # WebSocket client
│ │ ├── mcp/ # MCP handlers
│ │ │ ├── handler.ts # MCP JSON-RPC logic
│ │ │ ├── stdio.ts # stdio transport adapter
│ │ │ └── tools.ts # Tool definitions
│ │ └── cli.ts # Commander CLI
│ └── dashboard/ # Svelte web UI
│ └── src/
│ ├── App.svelte
│ └── lib/
├── extension/ # Chrome extension
├── workflows/ # Public workflow library
├── actions/ # User-created workflows
├── skills/ # Installed skill packs
└── run_logs/ # Execution history
Environment Variables
| Variable | Required For | Description |
|---|
OPENAI_API_KEY | llm.* steps | OpenAI API key for LLM workflows |
ANTHROPIC_API_KEY | llm.* steps | Anthropic API key (alternative) |
Development
pnpm install
pnpm build
pnpm start
pnpm cli list
pnpm cli status
Watch Mode
pnpm dev
pnpm dev:server
pnpm dev:dashboard
pnpm dev:core
SideButton is a general-purpose browser automation framework. When automating third-party platforms:
- Review Terms of Service: Many platforms prohibit or restrict automation. You are responsible for complying with the terms of any platform you automate.
- Account Risk: Automation may result in account restrictions or suspension on some platforms.
- Use Responsibly: Only automate actions you would perform manually. Respect rate limits and platform guidelines.
The authors do not endorse or encourage violations of third-party terms of service.
License
This project uses mixed licensing — see LICENSING.md:
- Engine, server, CLI, dashboard — Apache-2.0
- Browser extension — FSL-1.1-Apache-2.0 (converts to Apache-2.0 on 2029-03-15)