The official Python SDK for Model Context Protocol servers and clients
C-Rank Grade: A (Welcoming) - 55/100
External PR Merge Rate: 30%
Response Time: 17h
First Timer Success: 3%
modelcontextprotocol/python-sdk has a recorded first-timer success rate of 3.3%. Repositories ranked A typically provide actionable feedback during code reviews and actively nurture new community contributors.
Maintainers in modelcontextprotocol/python-sdk respond to incoming external pull requests in approximately 17.1 hours on average. Keeping PRs focused on single tasks and ensuring tests pass helps maintainers review faster.
The C-Rank™ system evaluates GitHub projects on a 0–100 scale using real data: PR merge rates, review turnaround time, active maintainer presence, and first-time contributor success. A score of 55.2 places modelcontextprotocol/python-sdk in the A tier.
The external contributor pull request merge rate for modelcontextprotocol/python-sdk is 29.9%, based on public PR activity from non-core contributors.
modelcontextprotocol/python-sdk currently has 1 active issue(s) tagged with beginner-friendly labels like "good first issue", "beginner", or "up-for-grabs".
Rigorous architecture standards (66% critical review signals). Ensure PRs strictly follow guidelines before requesting review in modelcontextprotocol/python-sdk.
Average Response Latency
Tracks hours until a maintainer leaves a review, comment, or PR response.
External Acceptance Rate
Percentage of community pull requests successfully merged into main.
First PR Conversion
Rate at which developers submitting their first repository PR succeed.
Show contributors that your repository actively reviews and merges external pull requests.
[](https://getmerged.abhishekco.de/modelcontextprotocol/python-sdk?utm_source=github&utm_medium=badge)
Historical health & responsiveness evolution
External PR acceptance
First PR success rate
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90% receive response in
Maintainer review activity heatmap & prime window prediction
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Detected: UTC
Maintainers are most responsive around 16:00 UTC (16:00 UTC in your timezone). Recommended submission window is Monday - Wednesday from 13:00 to 17:00 UTC (13:00 - 17:00 UTC local).
Maintainer Strategy: Maintainer Sweet Spot: PRs under 150 lines merge in ~11 hours (37% approval). Large PRs (>500 lines) take ~82 hours (15% approval). Keep your diff compact for rapid review.
Initial Checks I confirm that I'm using the latest version of MCP Python SDK I confirm that I searched for my issue in https://github.com/modelcontextprotocol/python-sdk/issues before opening this issue Description Hi! I ran into an issue where running the server with transport="stdio" causes subsequent stdio operations to fail after the server exits. Minimal reproduction from mcp.server.fastmcp import FastMCP mcp = FastMCP("Demo") mcp.run(transport="stdio") print("?") When using Ctrl+D to exit the server, the final print raises: Traceback (most recent call last): File "...", line 5, in <module> print("?") ValueError: I/O operation on closed file. I’m not sure if this is intended behavior though. Likely cause In stdio.py, stdio is wrapped like this: python-sdk/src/mcp/server/stdio.py Lines 44 to 47 in 5301298 if not stdin: stdin = anyio
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When evaluating whether to contribute to modelcontextprotocol/python-sdk, response velocity and maintainer engagement are crucial. GetMerged continuously tracks pull request trajectories, first-comment latency, and code review rounds to help developers avoid submitting pull requests to backlogged repositories.
Currently, maintainers of modelcontextprotocol/python-sdk acknowledge new external contributions in approximately 17 hours. Out of all submitted pull requests from non-core authors in the last 180-day window, 29.9% were successfully merged into the primary branch.
modelcontextprotocol/python-sdk has a recorded first-timer success rate of 3.3%. Repositories ranked Welcoming typically provide actionable feedback during code reviews and actively nurture new community contributors.
The initial maintainer response time averages ~17 hours. Keeping PRs scoped to single concerns and ensuring CI checks succeed will optimize review turnaround.
The C-Rank™ index scores repositories on a 0 to 100 scale using an objective formula: external PR merge rates, initial response speed, active maintainer count, and first-time contributor retention. A score of 55.2 places modelcontextprotocol/python-sdk in the Welcoming tier.
The external pull request merge rate is 29.9%. GetMerged isolates non-core community contributions so external developers get an accurate benchmark of PR acceptance probability.
Yes, modelcontextprotocol/python-sdk currently has 1 active issue(s) tagged with beginner-friendly labels. You can inspect these directly from the repository issues tab.
All metrics displayed for modelcontextprotocol/python-sdk are automatically retrieved via the public GitHub API and recalculated daily. Insider pull requests submitted by repository owners or organization members are excluded from merge rate calculations to preserve objective external contributor statistics.