---
title: "OpenCap Stack Overview"
description: "Open-source cap table and equity management platform — REST API, MCP server, OCTA v2.0"
canonical: "https://docs.ainative.studio/docs/opencapstack/overview"
last-updated: "2026-10-03T21:47:10.764Z"
---

# OpenCap Stack Overview

Source: https://docs.ainative.studio/docs/opencapstack/overview

> Open-source cap table and equity management platform — REST API, MCP server, OCTA v2.0

## OpenCap Stack

OpenCap Stack is an open-source cap table and equity management platform built for startups, growth-stage companies, and the AI agents that work with them. Every feature is available via a **REST API** and **MCP server** — so you can manage equity from code, from Claude, or from any MCP-compatible agent.

| | |
|---|---|
| **API Base** | `https://api.opencapstack.com/api/v1` |
| **MCP Package** | `@opencapstack/mcp-server@1.6.0` |
| **Schema Standard** | OCTA v2.0 (Open Cap Table Alliance) |
| **License** | MIT — self-host for free |
| **Docs** | `https://opencapstack.com/developers` |
| **GitHub** | `https://github.com/Open-Cap-Stack/opencapstack` |

---

## What You Can Build

- **Cap table dashboards** — query live ownership data, dilution models, vesting schedules
- **AI-powered equity agents** — let Claude manage grants, approve SAFEs, run waterfall analysis
- **Investor portals** — pull stakeholder data, generate reports, export to OCTA format
- **409A automation** — trigger valuations, retrieve results, integrate with finance workflows
- **Onboarding automation** — provision stakeholders, issue grants, send notifications programmatically

---

## Core Concepts

| Concept | Description |
|---------|-------------|
| **Stakeholder** | Any person or entity with equity — founder, investor, employee, advisor |
| **ShareClass** | Common, preferred (Series A/B/C), options pool |
| **EquityGrant** | Stock options, RSUs, warrants with vesting schedules |
| **SAFENote** | Simple Agreement for Future Equity with valuation cap and discount rate |
| **Valuation409A** | IRS-compliant fair market value determination |
| **FundraisingRound** | Round details, investors, dilution modeling |
| **Document** | Legal docs, grant agreements, board consents |

---

## Architecture

```
Your App / AI Agent
        │
        ├── REST API  ──►  https://api.opencapstack.com/api/v1
        │                           │
        └── MCP Server ─────────────┘
             (via Claude Code,               ZeroDB (primary DB)
              Cursor, Windsurf)              MinIO (document storage)
                                            AINative Auth (SSO)
```

---

## Guides in This Section

| Guide | What it covers |
|-------|---------------|
| [Authentication](./authentication) | AINative SSO, email/password, API keys, agent tokens |
| [REST API](./rest-api) | Full endpoint reference with examples |
| [MCP Server](./mcp-server) | 29 tools, setup for Claude Code / Cursor / Windsurf |
| [Builders Guide](./builders-guide) | End-to-end: build a cap table agent from scratch |
| [OCTA Schema](./octa-schema) | Data model, JSON examples, interoperability |
| [Self-Hosting](./self-hosting) | Run OpenCap Stack on your own infrastructure |

---

## Quick Start

**Option A — Call the REST API directly:**

```bash
## 1. Get a token
TOKEN=$(curl -s -X POST https://api.opencapstack.com/api/v1/auth/login \
  -H "Content-Type: application/json" \
  -d '{"email":"you@example.com","password":"yourpassword"}' \
  | python3 -c "import sys,json; print(json.load(sys.stdin)['token'])")

## 2. Query the cap table
curl https://api.opencapstack.com/api/v1/stakeholders \
  -H "Authorization: Bearer $TOKEN"
```

**Option B — Use the MCP server from Claude:**

```bash
npm install -g @opencapstack/mcp-server
```

Then in Claude: *"Show me the cap table summary"* — and it just works.

→ See the [MCP Server guide](./mcp-server) for full setup.