mcp

Model Context Protocol Python SDK by Model Context Protocol

Model Context Protocol SDK

Live Registry Versionv2.3.0Previous: v2.2.0Published 2026-10-02

Stability Grade

B (78/100)

90-Day Velocity

9 releases

Moderate cadence

Dependencies

19 direct

PYPI manifest

License

MIT

Verified on PYPI

Recommended Exact Pin: pip install "mcp==2.3.0"

PYPI Registry ->GitHub Repo ->

TL;DR Verdict & Quick Citation Summary (2026-10-24)Source: AgentBreakWatch Live PYPI Index

Model Context Protocol Python SDK (mcp) is currently at v2.3.0 on PYPI (published 2026-10-02), with a 90-day stability score of 78/100 (B) and HIGH schema drift risk across 9 releases in the past 90 days. v2.x restructures FastMCP lifespan context, StreamableHTTP session handling, and CallToolResult structuredContent validation. Production teams should pin pip install "mcp==2.3.0" rather than using unpinned @latest tags.

Breaking Changes & Tool Schema Drift Analysis

v2.x restructures FastMCP lifespan context, StreamableHTTP session handling, and CallToolResult structuredContent validation.

Watched Exports / MCP Tool Signatures:

FastMCPClientSessionstreamablehttp_clientCallToolResult

Before (Deprecated / Unpinned Pattern)

from mcp.client.sse import sse_client
async with sse_client("http://localhost:8000/sse") as (read, write):
    async with ClientSession(read, write) as session:
        await session.initialize()

After (Verified v2.3.0 Pattern)

from mcp.client.streamable_http import streamablehttp_client
async with streamablehttp_client("http://localhost:8000/mcp") as (read, write, _):
    async with ClientSession(read, write) as session:
        await session.initialize()

Frequently Asked Questions: mcp

What is the latest version of mcp on PYPI?

As of 2026-10-24, the latest stable version of mcp (Model Context Protocol Python SDK by Model Context Protocol) on PYPI is v2.3.0, published on 2026-10-02. It has shipped 9 releases in the last 90 days.

Does mcp v2.3.0 have breaking changes or MCP schema drift risk?

mcp currently carries a HIGH schema drift risk rating with a Stability Score of 78/100 (Grade B). v2.x restructures FastMCP lifespan context, StreamableHTTP session handling, and CallToolResult structuredContent validation.

How do I safely pin mcp in production?

Avoid unpinned @latest tags in production agent configs. Pin the exact verified version using `pip install "mcp==2.3.0"` and monitor FastMCP, ClientSession, streamablehttp_client, CallToolResult for parameter or schema changes.

30-Min Registry & Schema Poller