Previous round narrowed the framing too far in the other direction —
made it sound like Nextcloud OIDC is *the* IdP. The MCP server
actually supports any OIDC-compliant provider (Nextcloud's built-in
OIDC, Keycloak, AWS Cognito, Auth0, etc.) selected via
`OIDC_DISCOVERY_URL`. `NEXTCLOUD_OIDC_CLIENT_ID/SECRET` are generic
OIDC client credentials despite the Nextcloud-flavored naming.
Code references:
- IdP discovery: app.py:607-668 (auto-detects integrated vs external
by comparing discovered issuer to NEXTCLOUD_HOST)
- JWKS: unified_verifier.py:71-73 (dynamically discovered, not
hard-coded to Nextcloud)
- IdP selection knob: OIDC_DISCOVERY_URL (config.py)
Changes:
- login-flow-v2.md: redraw "How It Works" diagram to show the IdP as
a separate component; replace "Nextcloud OIDC" with "configurable
IdP" framing throughout; add OIDC_DISCOVERY_URL to the env-var
reference; clarify NEXTCLOUD_OIDC_CLIENT_ID/SECRET are generic OIDC
creds; rename "OAuth Endpoints" subtitle to point at "the configured
IdP".
- running.md: rewrite the OAuth Mode intro and Quick Start note to
mention IdP configurability and OIDC_DISCOVERY_URL.
- configuration.md: update Best Practices "For Production" multi-user
bullet to reference the IdP selector and generic-creds caveat.
- auth-flows.md: generalize Astrolabe-flow and Login Flow v2
characteristics bullets — IdP and JWKS source are configurable.
- keycloak-multi-client-validation.md: REMOVE the "deprecated"
banner I added in 35c115e. The doc covers active behavior in
external-IdP mode (realm-level token validation by user_oidc),
not retired direct-OAuth-to-Nextcloud architecture. Replaced with
a scope note pointing at when this applies.
oauth-impersonation-findings.md keeps its deprecation banner — that
doc *is* about the rejected service-account / impersonation path
(ADR-002 Tier 2, "Will Not Implement"), so the deprecation framing
remains correct there.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Nextcloud MCP Server
A production-ready MCP server that connects AI assistants to your Nextcloud instance.
Enable Large Language Models like Claude, GPT, and Gemini to interact with your Nextcloud data through a secure API. Create notes, manage calendars, organize contacts, work with files, and more - all through natural language conversations.
This is a dedicated standalone MCP server designed for external MCP clients like Claude Code and IDEs. It runs independently of Nextcloud (Docker, VM, Kubernetes, or local) and provides deep CRUD operations across Nextcloud apps.
Note
Looking for AI features inside Nextcloud? Nextcloud also provides Context Agent, which powers the Assistant app and runs as an ExApp inside Nextcloud. See docs/comparison-context-agent.md for a detailed comparison of use cases.
Tip
Don't want to self-host? Astrolabe Cloud is a managed hosting service for this MCP server, aimed at users and teams who want advanced features like background sync and semantic search without operating the infrastructure themselves. The service is currently under development — sign up on the landing page to join the early-adopter list.
Quick Start
Run the server locally with uvx (no installation required):
NEXTCLOUD_HOST=https://your.nextcloud.instance.com \
NEXTCLOUD_USERNAME=your_username \
NEXTCLOUD_PASSWORD=your_app_password \
uvx nextcloud-mcp-server run --transport stdio
Or add it directly to your MCP client configuration (e.g. claude_desktop_config.json or .claude/settings.json):
{
"mcpServers": {
"nextcloud": {
"command": "uvx",
"args": ["nextcloud-mcp-server", "run", "--transport", "stdio"],
"env": {
"NEXTCLOUD_HOST": "https://your.nextcloud.instance.com",
"NEXTCLOUD_USERNAME": "your_username",
"NEXTCLOUD_PASSWORD": "your_app_password"
}
}
}
}
Tip
Generate an app password in Nextcloud under Settings > Security > Devices & sessions instead of using your login password.
Docker
For full features including semantic search, run with Docker:
docker run -p 127.0.0.1:8000:8000 --rm \
-e NEXTCLOUD_HOST=https://your.nextcloud.instance.com \
-e NEXTCLOUD_USERNAME=your_username \
-e NEXTCLOUD_PASSWORD=your_app_password \
ghcr.io/cbcoutinho/nextcloud-mcp-server:latest
Then connect your MCP client (Claude Desktop, IDEs, mcp dev, etc.) to http://127.0.0.1:8000/mcp.
For Kubernetes, see cbcoutinho/helm-charts. For other deployment options and Compose profiles, see docs/installation.md.
Key Features
- 110+ MCP Tools - Comprehensive API coverage across 10 Nextcloud apps
- MCP Resources - Structured data URIs for browsing Nextcloud data
- Semantic Search (Experimental) - Optional vector-powered search for Notes, Files, News items, and Deck cards (requires Qdrant + Ollama)
- Document Processing - OCR and text extraction from PDFs, DOCX, images with progress notifications
- Flexible Deployment - Docker, Kubernetes (Helm chart), VM, or local installation
- Production-Ready Auth - Basic Auth with app passwords; multi-user via Login Flow v2 (OAuth-to-MCP supported, with app-password conversion to Nextcloud)
- Multiple Transports - streamable-http (default) and stdio
Supported Apps
| App | Tools | Capabilities |
|---|---|---|
| Notes | 7 | Full CRUD, keyword search, semantic search |
| Calendar | 20+ | Events, todos (tasks), recurring events, attendees, availability |
| Contacts | 8 | Full CardDAV support, address books |
| Files (WebDAV) | 12 | Filesystem access, OCR/document processing |
| Deck | 15 | Boards, stacks, cards, labels, assignments |
| Cookbook | 13 | Recipe management, URL import (schema.org) |
| Tables | 5 | Row operations on Nextcloud Tables |
| Sharing | 10+ | Create and manage shares |
| News | 8 | Feeds, folders, items, feed health monitoring |
| Collectives | 16 | Full CRUD on collectives, pages, and tags |
| Talk (spreed) | 6 | List conversations, read/post messages, mark as read, list participants |
| Semantic Search | 2+ | Vector search for Notes, Files, News items, and Deck cards (experimental, opt-in, requires infrastructure) |
Want to see another Nextcloud app supported? Open an issue or contribute a pull request!
Authentication
The MCP server authenticates to Nextcloud using app-specific passwords (Basic Auth). Three deployment modes are supported:
| Mode | Best for |
|---|---|
| Single-User (BasicAuth) | Personal use, development, single-user deployments |
| Multi-User (BasicAuth pass-through) | Multi-user setups where clients send credentials via Authorization header |
| Multi-User (Login Flow v2) | Multi-user / hosted deployments — clients authenticate to the MCP server via OAuth, and the server obtains a per-user app password from Nextcloud and uses it transparently |
OAuth-direct-to-Nextcloud is no longer supported (it required upstream patches to user_oidc that were never merged). Login Flow v2 replaces it for multi-user deployments and works with stock Nextcloud.
See docs/authentication.md for setup instructions.
Semantic Search
An experimental RAG pipeline that lets MCP clients find Nextcloud content by meaning rather than keywords — a query for "car" also surfaces notes about "vehicle" or "transportation". Disabled by default (ENABLE_SEMANTIC_SEARCH=false); requires a vector database and embedding service. See docs/semantic-search-architecture.md and docs/configuration.md.
Tip
Don't want to run Qdrant and an embedding service? Astrolabe Cloud (under development) provides semantic search and background sync as a managed service.
Documentation
- Installation — Docker, Compose profiles, local, VM
- Configuration — Environment variables, document processing, semantic search setup
- Authentication — Basic Auth, Login Flow v2
- Running the Server — Start, manage, troubleshoot
- App Documentation — Per-app guides (Notes, Calendar, Contacts, WebDAV, Deck, Cookbook, Tables)
- Semantic Search Architecture + Vector Sync UI
- Login Flow v2 — recommended multi-user setup (architecture, env vars, scope reference, troubleshooting)
- Troubleshooting · Comparison with Context Agent
Contributing
Contributions are welcome!
- Report bugs or request features: GitHub Issues
- Submit improvements: Pull Requests
- Development guidelines: CLAUDE.md
Security
Found a security issue? Do not open a public GitHub issue. Use GitHub's private vulnerability reporting, or email security@astrolabecloud.com if you can't use GitHub. See SECURITY.md for details.
License
This project is licensed under the AGPL-3.0 License. See LICENSE for details.
