exa-acp-mcp

A fork of exa-mcp-server that routes all Exa API requests through ACP (Agent Credential Proxy) for secure credential management.

What is ACP?

ACP is a credential injection proxy that sits between AI agents and APIs. Instead of giving agents direct access to API keys, ACP:

• Stores credentials securely outside the agent's context
• Injects credentials at the network layer when requests pass through the proxy
• Provides audit logging of all API access
• Allows credential rotation without updating agent configurations

Prerequisites

1. ACP installed and running - See ACP setup instructions
2. Exa plugin configured in ACP - With your Exa API credentials stored
3. ACP token - Created via acp token create

Installation

npm install -g exa-acp-mcp

Configuration

Environment Variables

Create a .env file in your working directory or set environment variables:

# Required: ACP token for proxy authentication
ACP_TOKEN=acp_xxxxxxxxxxxx

# Optional: ACP proxy URL (defaults to http://localhost:9443)
ACP_PROXY_URL=http://localhost:9443

The server automatically loads .env from the current working directory.

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "exa": {
      "command": "npx",
      "args": ["-y", "exa-acp-mcp"],
      "env": {
        "ACP_TOKEN": "acp_xxxxxxxxxxxx"
      }
    }
  }
}

Claude Code

claude mcp add exa -e ACP_TOKEN=acp_xxxxxxxxxxxx -- npx -y exa-acp-mcp

Or with a .env file in your project:

claude mcp add exa -- npx -y exa-acp-mcp

Available Tools

By default, two tools are enabled:

• web_search_exa - Real-time web search with content extraction
• get_code_context_exa - Code snippets, documentation, and examples from GitHub repos and docs

Additional Tools

Enable more tools using the tools parameter:

{
  "mcpServers": {
    "exa": {
      "command": "npx",
      "args": [
        "-y",
        "exa-acp-mcp",
        "tools=web_search_exa,get_code_context_exa,deep_search_exa,crawling_exa"
      ],
      "env": {
        "ACP_TOKEN": "acp_xxxxxxxxxxxx"
      }
    }
  }
}

All available tools:

• web_search_exa - Web search (enabled by default)
• get_code_context_exa - Code context search (enabled by default)
• deep_search_exa - Deep search with query expansion
• crawling_exa - Extract content from specific URLs
• company_research_exa - Company research
• linkedin_search_exa - LinkedIn search
• deep_researcher_start - Start async research task
• deep_researcher_check - Check research task status

How It Works

┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│   Claude    │────▶│     ACP     │────▶│   Exa API   │
│   Agent     │     │   Proxy     │     │             │
└─────────────┘     └─────────────┘     └─────────────┘
                          │
                    Injects Exa
                    API credentials

1. Agent makes request through this MCP server
2. Request is routed through ACP proxy on localhost:9443
3. ACP authenticates the request using the ACP_TOKEN
4. ACP injects Exa API credentials into the request
5. Request is forwarded to api.exa.ai

Differences from exa-mcp-server

| Feature | exa-mcp-server | exa-acp-mcp | |---------|---------------|-------------| | Credential handling | Direct EXA_API_KEY | Via ACP proxy | | API key exposure | In env/config | Never exposed to agent | | Audit logging | None | Via ACP | | Setup complexity | Simple | Requires ACP |

Troubleshooting

"ACP_TOKEN is required"

Set the ACP_TOKEN environment variable or add it to your .env file.

"ACP CA certificate not found"

Ensure ACP is installed and initialized. The CA cert should be at ~/.config/acp/ca.crt.

Connection refused on port 9443

Start the ACP proxy server. Check status with acp status.

License

MIT

Credits

• Original exa-mcp-server by Exa Labs
• ACP by Anthropic