Solr MCP Server

Name: solr-mcp
Author: apache

A Spring AI Model Context Protocol (MCP) server that provides tools for interacting with Apache Solr. Enables AI assistants like Claude to search, index, and manage Solr collections through the MCP protocol.

What's inside

🔍 Search Solr collections with filtering, faceting, and pagination
📝 Index documents in JSON, CSV, and XML
📁 Create collections with configurable shards, replicas, and configsets
📊 Manage collections and view statistics
🔧 Inspect schema
🔌 Transports: STDIO (Claude Desktop) and HTTP (MCP Inspector)
🔐 OAuth2 security with Auth0 (HTTP mode only)
🐳 Docker images built with Jib

Get started (users)

Prerequisites: Java 25+, Docker (and Docker Compose), Git
Start Solr with sample data:
```
docker compose up -d
```

Run the server:

STDIO mode (default):

Gradle:
```
./gradlew bootRun
```

JAR:

./gradlew build
java -jar build/libs/solr-mcp-1.0.0-SNAPSHOT.jar

Docker:

docker run -i --rm ghcr.io/apache/solr-mcp:latest

HTTP mode:

Gradle:
```
PROFILES=http ./gradlew bootRun
```

JAR:

PROFILES=http java -jar build/libs/solr-mcp-1.0.0-SNAPSHOT.jar

Docker:

docker run -p 8080:8080 --rm -e PROFILES=http ghcr.io/apache/solr-mcp:latest

For more options (custom SOLR_URL, Linux host networking) see the Deployment Guide: docs/DEPLOYMENT.md

Claude Desktop

Add this to your Claude Desktop config (macOS path shown); then restart Claude.

STDIO mode (default)

Using Docker:

{
  "mcpServers": {
    "solr-mcp": {
      "command": "docker",
      "args": ["run", "-i", "--rm", "ghcr.io/apache/solr-mcp:latest"],
        "env": {
            "SOLR_URL": "http://localhost:8983/solr/"
        }
    }
  }
}

Using JAR:

{
    "mcpServers": {
        "solr-mcp": {
            "command": "java",
            "args": [
                "-jar",
                "/absolute/path/to/solr-mcp-1.0.0-SNAPSHOT.jar"
            ],
            "env": {
                "SOLR_URL": "http://localhost:8983/solr/"
            }
        }
    }
}

HTTP mode

Using Docker:

{
    "mcpServers": {
        "solr-mcp": {
            "command": "docker",
            "args": [
                "run",
                "-p",
                "8080:8080",
                "--rm",
                "ghcr.io/apache/solr-mcp:latest"
            ],
            "env": {
                "PROFILES": "http",
                "SOLR_URL": "http://localhost:8983/solr/"
            }
        }
    }
}

Using JAR:

{
    "mcpServers": {
        "solr-mcp": {
            "command": "java",
            "args": [
                "-jar",
                "/absolute/path/to/solr-mcp-1.0.0-SNAPSHOT.jar"
            ],
            "env": {
                "PROFILES": "http",
                "SOLR_URL": "http://localhost:8983/solr/"
            }
    }
  }
}

Connecting to a running HTTP server

If you already have the MCP server running in HTTP mode (via Gradle, JAR, or Docker), you can connect Claude Desktop to
it using mcp-remote:

Running via Gradle:

PROFILES=http ./gradlew bootRun

Running locally (JAR):

PROFILES=http java -jar build/libs/solr-mcp-1.0.0-SNAPSHOT.jar

Running via Docker:

docker run -p 8080:8080 --rm -e PROFILES=http ghcr.io/apache/solr-mcp:latest

Then add to your claude_desktop_config.json:

{
    "mcpServers": {
        "solr-mcp-http": {
            "command": "npx",
            "args": [
                "mcp-remote",
                "http://localhost:8080/mcp"
            ]
        }
    }
}

More configuration options: docs/DEPLOYMENT.md#docker-images-with-jib

Claude Code

Add Solr MCP to Claude Code using the CLI or by adding a .mcp.json file to your project root.

STDIO mode (default)

Using Docker (CLI):

claude mcp add --transport stdio solr-mcp -- docker run -i --rm ghcr.io/apache/solr-mcp:latest

Using JAR (CLI):

claude mcp add --transport stdio -e SOLR_URL=http://localhost:8983/solr/ solr-mcp -- java -jar /absolute/path/to/solr-mcp-1.0.0-SNAPSHOT.jar

Or add to your project's .mcp.json:

Using Docker:

{
  "mcpServers": {
    "solr-mcp": {
      "type": "stdio",
      "command": "docker",
      "args": ["run", "-i", "--rm", "ghcr.io/apache/solr-mcp:latest"],
      "env": {
        "SOLR_URL": "http://localhost:8983/solr/"
      }
    }
  }
}

Using JAR:

{
  "mcpServers": {
    "solr-mcp": {
      "type": "stdio",
      "command": "java",
      "args": ["-jar", "/absolute/path/to/solr-mcp-1.0.0-SNAPSHOT.jar"],
      "env": {
        "SOLR_URL": "http://localhost:8983/solr/"
      }
    }
  }
}

HTTP mode

Start the server first (pick one):

# Gradle
PROFILES=http ./gradlew bootRun

# JAR
PROFILES=http java -jar build/libs/solr-mcp-1.0.0-SNAPSHOT.jar

# Docker
docker run -p 8080:8080 --rm -e PROFILES=http ghcr.io/apache/solr-mcp:latest

Then add to Claude Code:

claude mcp add --transport http solr-mcp http://localhost:8080/mcp

Or add to .mcp.json:

{
  "mcpServers": {
    "solr-mcp": {
      "type": "http",
      "url": "http://localhost:8080/mcp"
    }
  }
}

Security (OAuth2)

The Solr MCP server supports OAuth2 authentication when running in HTTP mode, providing secure access control for your
MCP tools.

Features

OAuth2 Resource Server: JWT token validation using Auth0 (or any OAuth2 provider)
HTTP Mode Only: Security is only active when using the http profile
CORS Support: Enabled for MCP Inspector compatibility
Machine-to-Machine: Uses Client Credentials flow for service authentication

Quick Setup

Configure Auth0 (see detailed guide: security-docs/AUTH0_SETUP.md)
- Create an Auth0 Application (Machine to Machine)
- Create an Auth0 API with your audience identifier
- Note your Domain, Client ID, Client Secret, and Audience

Set Environment Variable:

export OAUTH2_ISSUER_URI=https://your-tenant.auth0.com/
export PROFILES=http

Run the Server:
```
./gradlew bootRun
```

Get Access Token (using convenience script):

./scripts/get-auth0-token.sh --domain your-tenant.auth0.com \
  --client-id YOUR_CLIENT_ID \
  --client-secret YOUR_CLIENT_SECRET \
  --audience https://solr-mcp-api

Use the Token:

curl -H "Authorization: Bearer YOUR_TOKEN" \
  http://localhost:8080/mcp

For complete setup instructions, see security-docs/AUTH0_SETUP.md

Available MCP tools

Search

Tool	Description
`search`	Full-text search with filtering, faceting, sorting, and pagination

Indexing

Tool	Description
`index-json-documents`	Index documents from a JSON string into a Solr collection
`index-csv-documents`	Index documents from a CSV string into a Solr collection
`index-xml-documents`	Index documents from an XML string into a Solr collection

Collections

Tool	Description
`create-collection`	Create a new Solr collection (configSet, numShards, replicationFactor optional — default to `_default`, `1`, `1`)
`list-collections`	List all available Solr collections
`get-collection-stats`	Get statistics and metrics for a collection
`check-health`	Check the health status of a collection

Schema

Tool	Description
`get-schema`	Retrieve schema information for a collection

Available MCP Resources

MCP Resources provide a way to expose data that can be read by MCP clients. The Solr MCP Server provides the following resources:

Resource URI	Description
`solr://collections`	List of all Solr collections available in the cluster
`solr://{collection}/schema`	Schema definition for a specific collection (supports autocompletion)

Resource Autocompletion

The solr://{collection}/schema resource supports autocompletion for the {collection} parameter. MCP clients can use the completion API to get a list of available collection names.

MCP Inspector Resources