How to Configure Exa for Web Search in Agent-Reach

Agent-Reach provides free, API-key-less web search by connecting to the Exa semantic search engine through the mcporter MCP bridge, requiring only two CLI commands to enable.

Agent-Reach is an open-source framework that integrates external tools through the Model Context Protocol (MCP). To configure Exa for web search functionality, you install the mcporter bridge and register Exa's public MCP endpoint, enabling semantic search across the internet without managing API keys or credentials.

Prerequisites

Before configuring Exa, ensure you have Node.js installed on your system to run the mcporter CLI tool. The mcporter package is distributed via npm and acts as the MCP client bridge between Agent-Reach and external services.

Configuration Steps

Configuring Exa requires installing the MCP bridge and registering the Exa backend. These commands make the semantic search engine available to all Agent-Reach operations.

Step 1: Install the MCP Bridge

Install mcporter globally to enable the MCP client protocol:

npm install -g mcporter

This command provides the mcporter CLI used to register backends and route search queries.

Step 2: Register the Exa Backend

Register Exa's public MCP endpoint as the exa backend:

mcporter config add exa https://mcp.exa.ai/mcp

This stores the Exa configuration locally, allowing Agent-Reach to route web search requests through mcporter to Exa's semantic search engine.

How Exa Search Works in Agent-Reach

The integration relies on the ExaSearchChannel class defined in agent_reach/channels/exa_search.py. This class inherits from BaseChannel and implements the health check logic that validates your configuration.

When Agent-Reach initializes, the ExaSearchChannel.check() method runs mcporter config list to verify that the exa backend points to https://mcp.exa.ai/mcp. If the backend is present and reachable, the channel reports "ok" and becomes active for search operations.

Once active, calls to search methods in agent_reach/core.py delegate queries to mcporter, which forwards them to Exa's MCP endpoint. The read and search methods handle the response, returning semantic results without requiring an API key.

Verifying Your Configuration

Run the built-in diagnostics to confirm that Exa is properly configured:

agent-reach doctor | grep "Search"

When configured correctly, you should see output similar to:

Search (exa) – ok – 全网语义搜索可用（免费，无需 API Key）

This output indicates that ExaSearchChannel.check() successfully validated the mcporter configuration and the Exa backend is ready to handle queries.

Performing Web Searches

After configuration, you can perform searches via the CLI or programmatically through Python.

Searching via Command Line

Test the connection directly using mcporter:

mcporter call 'exa.web_search_exa(query: "latest AI news", numResults: 3)'

This returns a JSON payload containing the top three semantic results from Exa's index.

Searching via Python

Use the AgentReach class from agent_reach.core to perform searches in your application:

from agent_reach.core import AgentReach

# Initialize the library (uses the configured Exa backend)

ar = AgentReach()

# Perform a web search

results = ar.search("open source AI tools")
print(results)  # => list of result dicts with semantic matches

The search method automatically routes through the Exa backend when the channel is healthy, supporting queries across the general web, Reddit, and Twitter via site-specific filters.

Key Files and Implementation Details

Understanding the source code helps debug and extend the Exa integration:

• agent_reach/channels/exa_search.py: Contains the ExaSearchChannel class that validates the mcporter configuration and declares the channel health check. The check method ensures the Exa backend is registered before allowing search operations.

• agent_reach/core.py: Implements the core routing layer that forwards search calls to the active Exa backend when the channel reports healthy status.

• agent_reach/doctor.py: Runs diagnostics across all channels, including the Exa health check routine that executes mcporter config list.

• agent_reach/guides/setup-exa.md: Documents the step-by-step installation and verification commands for users setting up Exa for the first time.

Summary

• Install mcporter via npm install -g mcporter to enable the MCP bridge protocol.
• Register the Exa backend using mcporter config add exa https://mcp.exa.ai/mcp to connect to the semantic search engine.
• Verify the configuration with agent-reach doctor, which runs ExaSearchChannel.check() to confirm the backend is reachable.
• The integration requires no API keys and supports semantic search across the internet, Reddit, and Twitter through site-restricted queries.

Frequently Asked Questions

Do I need an Exa API key to use web search in Agent-Reach?

No. Agent-Reach connects to Exa through the public MCP endpoint at https://mcp.exa.ai/mcp via the mcporter bridge. This architecture eliminates the need for personal API keys or credentials, making the search functionality free to use once configured.

What does the ExaSearchChannel.check() method verify?

The check method executes mcporter config list to confirm that an exa backend entry exists and points to the correct MCP endpoint. It returns "ok" only when the backend is properly registered and reachable, ensuring that subsequent search calls will route correctly through mcporter.

Can I search specific sites like Reddit or Twitter with Exa?

Yes. Exa supports semantic search with site restrictions. When querying through Agent-Reach, you can specify domain filters to limit results to specific platforms such as Reddit or Twitter, allowing targeted search within particular communities.

Where is the Exa configuration stored after running mcporter config add?

The mcporter CLI stores backend configurations in your local environment. You can inspect the stored configuration by running mcporter config list, which outputs all registered backends including the Exa entry pointing to https://mcp.exa.ai/mcp.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}