idea-reality-mcp: MCP server checks for existing tools before Claude writes code

Pre-build market validation for AI coding agents

A developer created an MCP server called idea-reality-mcp that performs automated market research before writing code with Claude. The tool addresses the common problem of spending hours building something only to discover existing solutions.

How it works

The server scans multiple data sources to determine if similar tools already exist:

• GitHub Search API (repo count + star distribution)
• HN Algolia API (discussion volume)
• npm registry (quick mode skips this)
• PyPI (deep mode)
• Product Hunt (optional, requires token)

Unlike asking an LLM "does this exist?" which relies on guessing, this tool actually searches real APIs and returns quantitative data.

Integration with CLAUDE.md

The key integration involves adding four lines to your CLAUDE.md file:

## Pre-build Reality Check
Before creating any new project, feature, or tool, run `idea_check` with a one-line description.
- If reality_signal > 80: STOP. Warn me about high competition before proceeding.
- If reality_signal > 60: Proceed with caution. Suggest how to differentiate.
- If reality_signal < 40: Green light. Proceed normally.

This causes Claude to automatically check the market whenever you say "build me a ___".

Example output

The tool returns a "reality signal" score from 0-100, where higher numbers indicate more competition. Example output:

Reality Signal: 87/100
Top competitors found:
- existing-tool-1 (2.3k stars)
- existing-tool-2 (890 stars)
Recommendation: High competition. Consider focusing on [specific gap].

Technical details

The tool is open source and runs as a standard MCP server (stdio or HTTP). It works with Claude Code, Cursor, Windsurf, and any MCP-compatible client. Ready-made instruction templates are available for each client. The GitHub repository contains the full implementation and scoring formula.

This approach provides concrete data about market saturation before investing development time, helping developers avoid reinventing existing solutions and identify genuine gaps in the ecosystem.