---
title: "Legacy MCP HTTP+SSE JSON-RPC message handler"
method: POST
path: "/messages"
tags: ["MCP"]
---

# Legacy MCP HTTP+SSE JSON-RPC message handler

`POST /messages`

## Request

- Base URL: `https://api.m2msentinel.com`
- URL: `https://api.m2msentinel.com/messages`
- Auth: none required

Compatibility message endpoint paired with /sse for protocol 2024-11-05 clients. New clients POST to /mcp.

## Request body

- object

## Response `200`

MCP JSON-RPC response

- object

---

[API](https://skmtc.dev/m2msentinel/apis/m2m-sentinel-base-contract-capability-checks-before-you-sign.md) · [All operations](https://skmtc.dev/m2msentinel/apis/m2m-sentinel-base-contract-capability-checks-before-you-sign/llms.txt) · [OpenAPI document](https://skmtc.dev/m2msentinel/apis/m2m-sentinel-base-contract-capability-checks-before-you-sign/revisions/2dadd4e704fd?raw)