DiffCI

by @DiffCI · io.github.DiffCI/diffci

Fail-closed, change-aware verification for AI coding agents with affected-test guidance.

OnlineRemote + local

Category: Developer tools
Connection: Remote (HTTP)
Tools: 3 reported
Status: Online

Connect it to your AI

Claude Code

claude mcp add --transport http diffci https://diffci.com/mcp/v1

Claude, ChatGPT, Cursor and other apps

Add it as a custom connector with this URL (Streamable HTTP):

https://diffci.com/mcp/v1

Or run it locally (npm)

claude mcp add diffci -- npx -y @diffci.com/diffci@0.3.21

Cursor, VS Code and other apps (mcp.json)

{
  "mcpServers": {
    "diffci": {
      "url": "https://diffci.com/mcp/v1"
    }
  }
}

Tools it offers

3 tools, as the server itself reported during our check on Oct 31, 2026.

diffci_validation_planPlan change-aware CI validation, affected-test selection, test impact analysis, or GitHub Actions workflow checks. Returns a safe local DiffCI command without accessing the checkout or executing it.
diffci_interpret_reportValidate and summarize a DiffCI observation report, including selective or full mode, affected-test counts, fallbacks, non-interference evidence, and the conservative next action.
diffci_verify_workflow_textPerform a stateless preliminary safety check of GitHub Actions YAML: dedicated observer job, continue-on-error, dependency isolation, read-only permissions, and immutable DiffCI references.

Questions

What is the DiffCI MCP server?

Fail-closed, change-aware verification for AI coding agents with affected-test guidance. It is made by @DiffCI and listed in the official MCP Registry as io.github.DiffCI/diffci. MCP (Model Context Protocol) is the open standard that lets AI apps like Claude, ChatGPT and Cursor use outside tools.

How do I add DiffCI to Claude?

In the Claude app or claude.ai, open Settings, then Connectors, choose "Add custom connector" and paste https://diffci.com/mcp/v1. In Claude Code, run: claude mcp add --transport http diffci https://diffci.com/mcp/v1

How do I add DiffCI to ChatGPT?

ChatGPT can use remote MCP servers as connectors. In ChatGPT settings, under Apps and Connectors, turn on developer mode if asked, create a new connector and paste https://diffci.com/mcp/v1.

How do I add DiffCI to Cursor?

Open Cursor settings, go to MCP, choose "Add new MCP server" (or edit ~/.cursor/mcp.json) and add: { "mcpServers": { "diffci": { "url": "https://diffci.com/mcp/v1" } } }

Does DiffCI work right now?

Yes. It responded when we last checked on 31 Oct 2026. We check remote MCP servers every day.

What can DiffCI do?

It gives your AI 3 tools, including diffci_validation_plan, diffci_interpret_report, diffci_verify_workflow_text. The full list is on this page.

Is this your server? Get the badge for your README

Markdown (GitHub README)

[![Listed on chen.media/mcp](https://chen.media/mcp/badge/github-diffci-diffci.svg)](https://chen.media/mcp/github-diffci-diffci)

HTML (switches to dark mode on its own)

<a href="https://chen.media/mcp/github-diffci-diffci"><picture><source media="(prefers-color-scheme: dark)" srcset="https://chen.media/mcp/badge/github-diffci-diffci.svg?theme=dark"><img src="https://chen.media/mcp/badge/github-diffci-diffci.svg" alt="Listed on chen.media/mcp" height="40"></picture></a>

DiffCI

Connect it to your AI

Claude Code

Claude, ChatGPT, Cursor and other apps

Or run it locally (npm)

Cursor, VS Code and other apps (mcp.json)

Tools it offers

Questions

Markdown (GitHub README)

HTML (switches to dark mode on its own)

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