Reply MCP server for AI agents and assistants

Securely connect your AI agents and chatbots (Claude, ChatGPT, Cursor, etc) with Reply MCP or direct API to automate email outreach, send and track campaigns, monitor reply rates, and organize leads—all through natural language.

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Api Key

Reply.io is a sales engagement platform for automating multichannel outreach and managing email campaigns. It helps sales teams boost productivity by tracking responses and centralizing campaign performance.

21 Tools

Try Reply now

Type what you want done — sign in and watch it run live in the Tool Router playground.

TOOL ROUTER PLAYGROUND
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TOOLS

Supported Tools

Every Reply action and event your agent gets out of the box.

Create Personal List

Tool to add a new personal list on the People page.

Delete Email Account

Tool to delete a specific email account.

Delete List By ID

Tool to delete a list by its ID.

Delete Sequence

Tool to delete a sequence.

Delete User

Tool to delete a user.

Generate ULID

Generate ULID

Get All Lists

Tool to retrieve all available people lists.

Get full blacklist of domains and emails

Tool to retrieve the full list of blacklisted domains and emails.

Get all campaign schedules

Retrieves all campaign schedules from Reply.

Get Campaigns For Contact

Tool to retrieve campaigns a contact belongs to by contact ID.

Get Contacts in List by ID

Tool to retrieve contacts in a specific personal list.

Get List by ID

Tool to return a specific people list by its ID.

Get templates list

Retrieves all email templates from Reply.

List Campaigns

Tool to list all campaigns (sequences).

List Contacts Basic

Tool to list contacts.

Reply.io List Email Accounts

Tool to list all email accounts.

Mark Contact As Finished

Marks a contact (by email) or all contacts under a domain as finished in all Reply.

Mark Contact as Replied

Tool to mark a contact as replied in all campaigns by email or domain.

Move Contacts to Lists

Tool to move one or more contacts to specified lists.

Remove Domain from Blacklist

Tool to remove the specified domain from the blacklist.

Search Contacts by Email

Tool to search contacts by email.

SETUP GUIDE

Connect Reply MCP Tool with your Agent

1

Install Composio

typescript
npm install @composio/core ai @ai-sdk/mcp @ai-sdk/openai
Install the Composio SDK and your agent framework
2

Create a session with MCP enabled

typescript
import { Composio } from "@composio/core";

const composio = new Composio();
const { mcp } = await composio.create("your-user-id", {
  toolkits: ["reply"],
  mcp: true,
});
Create a session scoped to Reply and read its MCP URL and headers
3

Connect your agent to the MCP server

typescript
import { createMCPClient } from "@ai-sdk/mcp";
import { openai } from "@ai-sdk/openai";
import { generateText, stepCountIs } from "ai";

const client = await createMCPClient({
  transport: { type: "http", url: mcp.url, headers: mcp.headers },
});

const { text } = await generateText({
  model: openai("gpt-5.6-sol"),
  tools: await client.tools(),
  prompt: "List all active email campaigns running this week",
  stopWhen: stepCountIs(10),
});

console.log(text);
await client.close();
Pass the session's MCP URL and headers to your agent and run a Reply request
SETUP GUIDE

Connect Reply API Tool with your Agent

1

Install Composio

typescript
npm install @composio/core @composio/openai openai
Install the Composio SDK, the OpenAI provider, and the OpenAI SDK
2

Create a Composio session

typescript
import OpenAI from "openai";
import { Composio } from "@composio/core";
import { OpenAIResponsesProvider } from "@composio/openai";

const composio = new Composio({ provider: new OpenAIResponsesProvider() });
const client = new OpenAI();

const session = await composio.create("your-user-id", { toolkits: ["reply"] });
const tools = await session.tools();
Initialize Composio with the OpenAI Responses provider and create a session scoped to Reply
3

Run Reply tools with your agent

typescript
let response = await client.responses.create({
  model: "gpt-5.6-sol",
  tools,
  input: [{ role: "user", content: "List all active email campaigns running this week" }],
});

while (response.output.some((o) => o.type === "function_call")) {
  const outputs = await composio.provider.handleToolCalls(session, response.output);
  response = await client.responses.create({
    model: "gpt-5.6-sol",
    tools,
    previous_response_id: response.id,
    input: outputs,
  });
}

console.log(response.output_text);
Send a request, execute the Reply tool calls through the session, and print the final answer

Why Use Composio?

AI Native Reply Integration

  • Supports both Reply MCP and direct API based integrations
  • Structured, LLM-friendly schemas for reliable tool execution
  • Rich coverage for reading, writing, and querying your Reply data

Managed Auth

  • Built-in API key management with automatic rotation
  • Central place to manage, scope, and revoke Reply access
  • Per user and per environment credentials instead of hard-coded keys

Agent Optimized Design

  • Tools are tuned using real error and success rates to improve reliability over time
  • Comprehensive execution logs so you always know what ran, when, and on whose behalf

Enterprise Grade Security

  • Fine-grained RBAC so you control which agents and users can access Reply
  • Scoped, least privilege access to Reply resources
  • Full audit trail of agent actions to support review and compliance

Rolling this out across your team?

Give your team centralized access control across every framework with Composio’s MCP Gateway.

EXPLORE MCP GATEWAY
FAQ

Frequently asked questions

Yes, Reply requires you to configure your own API key credentials. Once set up, Composio handles secure credential storage and API request handling for you.

Yes! Composio's Tool Router enables agents to use multiple toolkits. Learn more.

Yes. Composio is SOC 2 Type II compliant and is built to keep your Reply connection and credentials secure. OAuth tokens and API keys are encrypted, and sensitive customer data is protected at rest and in transit.

Composio also undergoes independent security testing and continuously monitors its systems for security threats. You can review the latest reports and policies in the Composio Trust Center.

Composio maintains and updates all toolkit integrations automatically, so your agents always work with the latest API versions.

Create the key in your Reply account settings, then paste it once on Composio's connection page. Composio stores it encrypted and uses it only for the Reply actions your agent runs. Nobody else in your workspace can read it, and you can revoke it inside Reply at any time.

When you connect a Reply account through Composio, every action runs under that account, so anything the agent creates, sends, or changes shows up in Reply as done by you. Keep an approval step in your prompt for actions with side effects, such as sending or deleting, and have the agent draft first.

Whatever the credentials you connect allow inside Reply. If Reply lets you scope a key to specific permissions, create a scoped one so the agent can only do what you intend. You can revoke the key inside Reply at any time.

Yes. Composio supports multiple connected accounts for the same app, and that works in Claude, ChatGPT, or any other assistant you connect through Composio. Give each Reply connection a name such as work or personal, and the assistant uses the one you mention in the request. Each account keeps its own credentials and nothing is merged.

The connection stops working the moment Reply rejects the old key. Create a new key in Reply and reconnect the account from the Composio dashboard or by asking your agent to reconnect Reply. Nothing else changes.

Composio's free Hobby plan includes 100,000 tool calls per month with no credit card, which covers most personal Reply use. Paid plans add higher limits and team features. Your Reply plan and its API limits still apply as usual.

Built-in connectors usually give one AI access to a limited set of apps. Many people use Composio because it lets their AI connect to more apps than it normally supports, or connect to multiple accounts for the same app (e.g. connect Claude to multiple Reply accounts).

With Composio, you connect Reply once and then use it across different AI assistants without setting it up separately in each one. Connect your apps to Composio once, then connect Composio to whichever AI you use, whether that's Claude, ChatGPT, Hermes, or your own custom assistant.

Start with Reply.It takes 30 seconds.

Managed auth, hosted MCP servers, and every Reply tool your agent needs.Free to start.

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