argocd-mcp

The entire ArgoCD API, exposed to LLMs via MCP.
103+ endpoints. 2 tools. Zero hardcoded handlers.

Quick Start • How It Works • OAuth • Configuration

Most ArgoCD MCP servers hardcode a few operations: list apps, sync, get status. When ArgoCD adds a new feature, you wait for the maintainer to add it.

argocd-mcp takes a different approach, inspired by Cloudflare's MCP server which covers 2500+ endpoints with only 2 tools. It reads ArgoCD's OpenAPI spec at startup and exposes every endpoint through just 2 tools: search and execute. New ArgoCD version? Restart the server. Done.

• 103+ endpoints, 2 tools, ~200 tokens of system prompt
• Works with Claude Desktop, Claude Code, Cursor, or any MCP client
• No code per endpoint — the OpenAPI spec is the source of truth
• Two auth modes: static token or OAuth via ArgoCD Dex (per-user RBAC)
• Read-only mode — disable all write operations with a single flag
• Resource scoping — restrict which ArgoCD resources are exposed with ALLOWED_RESOURCES
• Prompt templates — pre-packaged workflows for common operations (unhealthy apps, diff, rollback, logs)
• Audit logging — structured JSON logs for every tool call (user, method, path, status, duration)
• Optional semantic search via Ollama embeddings

How It Works

graph TD
    A[ArgoCD /swagger.json] -->|Fetch at startup| B[Parse Swagger 2.0]
    B --> C[103+ Endpoints in memory]
    C --> D[search_operations]
    C --> E[execute_operation]
    D -->|LLM discovers endpoints| F[Returns method, path, summary, params]
    E -->|LLM calls API| G[Proxies to ArgoCD with user token]

1. At startup, the server fetches ArgoCD's Swagger spec
2. It parses every endpoint (method, path, summary, parameters, request body schema)
3. search_operations — keyword or semantic search across all endpoints
4. execute_operation — generic HTTP proxy to ArgoCD

Quick Start

Helm Chart (Kubernetes)

helm install argocd-mcp oci://ghcr.io/matthisholleville/charts/argocd-mcp \
  --set argocd.baseURL=https://argocd.example.com \
  --set argocd.token=your-token

See all configuration options in charts/argocd-mcp/values.yaml.

Static Token (simple)

Best for local dev, CI/CD, or single-user setups. Uses a static ArgoCD API token.

Claude Code

claude mcp add argocd -s user -- \
  docker run --rm -i \
  -e ARGOCD_BASE_URL=https://argocd.example.com \
  -e ARGOCD_TOKEN=your-token \
  ghcr.io/matthisholleville/argocd-mcp:latest

Claude Desktop

Add to your Claude Desktop MCP config (claude_desktop_config.json):

{
  "mcpServers": {
    "argocd": {
      "command": "docker",
      "args": ["run", "--rm", "-i",
        "-e", "ARGOCD_BASE_URL=https://argocd.example.com",
        "-e", "ARGOCD_TOKEN=your-token",
        "ghcr.io/matthisholleville/argocd-mcp:latest"
      ]
    }
  }
}

OAuth via ArgoCD Dex (per-user RBAC)

Best for multi-user, production setups. Each user authenticates with their own identity via ArgoCD's built-in Dex. No static token needed — the user's Dex id_token is forwarded to ArgoCD, which applies its RBAC policies per user.

Step 1: Start the server

docker run -p 8080:8080 \
  -e ARGOCD_BASE_URL=https://argocd.example.com \
  -e MCP_TRANSPORT=http \
  -e AUTH_MODE=oauth \
  -e DEX_CLIENT_ID=argo-cd-cli \
  -e SERVER_BASE_URL=http://localhost:8080 \
  ghcr.io/matthisholleville/argocd-mcp:latest

Step 2: Connect your MCP client

Claude Code

claude mcp add --transport http --callback-port 9382 argocd http://localhost:8080/mcp

Then run /mcp inside Claude Code to authenticate via the browser.

Claude Desktop

Claude Desktop requires a publicly accessible URL (the OAuth redirect goes through claude.ai). Expose the server via a reverse proxy or ngrok, then set SERVER_BASE_URL accordingly.

Add the public URL as a remote MCP server in Settings > Connectors (e.g. https://mcp.example.com/mcp). Claude Desktop handles the OAuth flow automatically.

staticClients:
  - id: argo-cd-cli
    name: Argo CD CLI
    public: true
    redirectURIs:
      - http://localhost
      - http://localhost:8085/auth/callback
      - http://localhost:9382/callback
      - https://claude.ai/api/mcp/auth_callback

Semantic Search (optional)

Enable Ollama-powered vector search for better results on natural language queries:

docker compose up --build -d  # Starts Ollama + argocd-mcp with embeddings

Set EMBEDDINGS_ENABLED=true, OLLAMA_URL, and EMBEDDINGS_MODEL (defaults to nomic-embed-text).

Read-Only Mode (optional)

Set DISABLE_WRITE=true to prevent any disruptive action on your cluster. When enabled:

• Write endpoints are hidden — POST, PUT, PATCH, DELETE operations are filtered out from the search index, so the LLM never discovers them.
• Write execution is blocked — even if a caller manually crafts an execute_operation request with a write method, it is rejected.
• Read operations work normally — GET, HEAD, OPTIONS are unaffected.

This is ideal for production environments, demos, or any setup where you want LLMs to observe but never modify your ArgoCD resources.

# Claude Code
claude mcp add argocd -s user -- \
  docker run --rm -i \
  -e ARGOCD_BASE_URL=https://argocd.example.com \
  -e ARGOCD_TOKEN=your-token \
  -e DISABLE_WRITE=true \
  ghcr.io/matthisholleville/argocd-mcp:latest

Resource Scoping (optional)

Set ALLOWED_RESOURCES to restrict which ArgoCD resource types the LLM can discover and call. This filters both search results and blocks execution of out-of-scope endpoints.

# Only expose application and version endpoints
ALLOWED_RESOURCES=ApplicationService,VersionService

Composes with DISABLE_WRITE:

# Read-only access to applications only
DISABLE_WRITE=true
ALLOWED_RESOURCES=ApplicationService

Available resource tags (from ArgoCD's OpenAPI spec):

Matching is case-insensitive (applicationservice works).

Rate Limiting (optional)

Protect ArgoCD from excessive API calls by setting RATE_LIMIT. Only execute_operation is rate limited — search is local and not affected.

RATE_LIMIT=10              # 10 requests/sec per user
RATE_LIMIT_BURST=20        # allow short bursts up to 20

Prompt Templates

Pre-packaged workflows for common ArgoCD operations. MCP clients (Claude Desktop, Cursor) show these as selectable prompts in their UI.

Each prompt guides the LLM through a step-by-step workflow using search_operations and execute_operation. No additional tools are needed.

Audit Logging

Audit logging is enabled by default. Every search_operations and execute_operation call emits a structured JSON log entry to stderr:

{"time":"2026-03-22T10:00:00Z","level":"INFO","msg":"audit","tool":"execute_operation","method":"GET","path":"/api/v1/applications","blocked":false,"duration_ms":142,"status_code":200,"user":"[email protected]"}

Each entry includes:

• tool — search_operations or execute_operation
• user — email from the OAuth token (empty in static token mode)
• method / path — the ArgoCD API call (execute) or query (search)
• status_code — upstream HTTP response code
• blocked — true if the call was rejected by DISABLE_WRITE or ALLOWED_RESOURCES
• duration_ms — round-trip time in milliseconds
• error — error message (logged at ERROR level when present)

Set AUDIT_LOG=false to disable.

Configuration

Build from source

make build
ARGOCD_BASE_URL=https://argocd.example.com ARGOCD_TOKEN=xxx ./bin/argocd-mcp

License

MIT