Integrate MCP

MCP is an open standard for securely connecting AI assistants to external data sources and tools. In Zero Runtime AI Agents, attach MCP servers to auto-discover services, databases, and APIs. The agent picks and runs the right tools and turns results into natural responses.

How It Works

MCP tools are automatically discovered and made available to your agent, which intelligently chooses which tools to use based on user requests. When a user asks for information that requires external data, the agent will:

Identify the need

Detect that the user’s request requires external data.

Select tools

Choose the appropriate tools from the available MCP servers.

Execute

Run the tools with the relevant parameters.

Respond

Process the results and provide a natural language response.

This integration allows your voice agent to access real-time data and external services while maintaining a natural conversational flow.

Transport Methods

Zero Runtime supports two transport methods for MCP servers.

Transport	Communication	Best For
STDIO	Direct process communication with local Python scripts	Custom tools and functions, server-side integrations
HTTP (Streamable HTTP or SSE)	Network-based communication with external MCP services	Third-party integrations, remote MCP servers

Example

Pass MCP servers to the agent via the mcp_servers parameter. Use MCPServerStdio for local scripts and MCPServerHTTP for remote services.

import sys
from zeroruntime import Agent, MCPServerStdio, MCPServerHTTP

class MyVoiceAgent(Agent):
    def __init__(self, pipeline):
        super().__init__(
            agent_id="assistant",
            instructions="You are a helpful assistant with access to real-time data.",
            pipeline=pipeline,
            mcp_servers=[
                # STDIO - local script
                MCPServerStdio(
                    executable_path=sys.executable,
                    process_arguments=["mcp_stdio_example.py"],
                ),
                # HTTP - remote service
                MCPServerHTTP(
                    endpoint_url="https://your-mcp-service.com/api/mcp",
                    request_headers={"Authorization": "Bearer <token>"},
                ),
            ],
        )

import { Agent, MCPServerStdio, MCPServerHTTP } from '@zeroruntime/js-sdk';

class MyVoiceAgent extends Agent {
  constructor(pipeline) {
    super({
      agent_id: 'assistant',
      instructions: 'You are a helpful assistant with access to real-time data.',
      pipeline,
      mcp_servers: [
        // STDIO - local script
        MCPServerStdio({
          executable_path: 'python3',
          process_arguments: ['mcp_stdio_example.py'],
        }),
        // HTTP - remote service
        MCPServerHTTP({
          endpoint_url: 'https://your-mcp-service.com/api/mcp',
          request_headers: { Authorization: 'Bearer <token>' },
        }),
      ],
    });
  }
}

The agent auto-discovers every tool exposed by each server and chooses among them at runtime, so you don’t register tools individually.

Server options

`MCPServerStdio` (local process)

Parameter	Type	Default	Description
`executable_path`	`str`	required	Program to run (e.g. `sys.executable` for Python).
`process_arguments`	`list[str]`	`[]`	Its arguments — typically the server script.
`environment_vars`	`dict[str, str] \| None`	`None`	Environment for the child. `None` inherits this process’s, which is usually what you want: the server needs the same API keys you already have.
`working_directory`	`str \| Path \| None`	`None`	Directory to run it in.
`session_timeout`	`float`	`5.0`	Seconds to wait for the connection and for each tool call. 5 is tight for a server that starts an interpreter; pass `30` for those.

`MCPServerHTTP` (remote service)

Parameter	Type	Default	Description
`endpoint_url`	`str`	required	The server’s URL.
`request_headers`	`dict[str, str] \| None`	`None`	Sent with every request — an API key usually lives here. Read in this process, so the credential stays with you.
`connection_timeout`	`float`	`10.0`	Seconds to wait for the connection.
`stream_read_timeout`	`float`	`300.0`	Seconds a quiet stream may stay open. Long by default: an MCP server that has nothing to say is not broken.
`session_timeout`	`float`	`5.0`	Seconds to wait for the session, and for each tool call.

Get started

Modalities

Configure Pipeline

Tools and Capabilities

Turn Detection and Interruptions

Telephony Agents

Context Management

Observability and Monitoring

How It Works

Transport Methods

Example

Server options

`MCPServerStdio` (local process)

`MCPServerHTTP` (remote service)

What’s Next

Function Tools

RAG

References

Examples

MCP Client

Examples

MCP Client

​How It Works

​Transport Methods

​Example

​Server options

​MCPServerStdio (local process)

​MCPServerHTTP (remote service)

​What’s Next

Function Tools

RAG

​References

​Examples

MCP Client

​Examples

MCP Client

How It Works

Transport Methods

Example

Server options

`MCPServerStdio` (local process)

`MCPServerHTTP` (remote service)

What’s Next

References

Examples

Examples