Developer Tools stdio

OpenSpec

Created by Fission-AI

Facilitates spec-driven development to ensure alignment between humans and AI coding assistants before any code is written.

How to Connect & Install

Select your client or environment below to copy the verified, ready-to-run installation configuration.

1-line autonomous agent setup instruction. Paste into Claude Code, Codex CLI, or Cursor Agent:
Fetch and configure Model Context Protocol (MCP) server OpenSpec from https://www.fastmcp.dev/server/openspec

Agents automatically discover, install, and execute the server spec without manual token setup.

Connect via direct Stateless MCP v2 / Streamable HTTP endpoint or JSON-RPC:
https://github.com/fission-ai/openspec

Stateless edge endpoint compliant with MCP 2024-11-05 and v2 draft protocol specs.

Includes server instructions and tool definitions for Claude:
claude mcp add openspec -- npx -y openspec

Run in terminal to register server in current project or pass --scope user for global availability.

Configures server instructions and tools for OpenAI Codex & ChatGPT Desktop:
[mcp_servers.openspec] command = "npx" args = ["-y","openspec"]

Applies to ChatGPT Desktop app, Codex CLI, and IDE extension across your Codex host.

Add to Cursor project settings (.cursor/mcp.json) or Cursor Settings > Features > MCP:
{ "mcpServers": { "openspec": { "type": "stdio", "command": "npx", "args": [ "-y", "openspec" ] } } }

Commit to version control to allow teammates to connect immediately.

Install as an autonomous Agent Skill using the standard skills CLI:
npx skills add https://github.com/fission-ai/openspec

Standard agent skill installer compatible with Claude Code, Cursor, and agy harnesses.

Server Guidance & Instructions OpenAI & Claude Spec Compliant
OpenSpec: Facilitates spec-driven development to ensure alignment between humans and AI coding assistants before any code is written. Key capabilities: Lightweight spec-driven workflow requiring no API keys and minimal setup.; Supports native slash commands for a wide range of AI coding assistants (e.g., Claude Code, Cursor, GitHub Copilot, Amazon Q Developer).; Structured change tracking for proposals, tasks, and spec deltas, with an archiving mechanism..

Codex and Claude read this instruction prompt during initialization to orchestrate cross-tool workflows and rate limits.

Top Core Functions
01 Manage project context and conventions
02 Track structured project change proposals
03 Maintain project specs using commands