Install

Codex:

npx -y nullcost-plugin@latest install codex

Claude, Cursor, and Windsurf:

npx -y nullcost-plugin@latest install claude
npx -y nullcost-plugin@latest install cursor
npx -y nullcost-plugin@latest install windsurf

Any MCP app with a JSON config file:

npx -y nullcost-plugin@latest install mcp --config /path/to/mcp.json

The installer copies the plugin into ~/.nullcost, installs the local MCP server dependencies, backs up any config file before editing it, and runs a doctor check.

Use

Restart or reload your coding app, then ask normal questions:

find me a hosting provider with a free tier
what are cheap and free email hosts?
best free-tier auth for a small SaaS
free Postgres options for a Next.js project

Nullcost answers from the hosted catalog and avoids extra web-search drift after a successful catalog result unless you explicitly ask for live verification.

Community-Powered Savings

Nullcost can show reviewed community referral, affiliate, and credit codes next to the official provider link. The point is not to sell the top slot; it is to let builders share real signup benefits with the next person choosing a tool.

Verify

npx -y nullcost-plugin@latest doctor --quick

Full catalog smoke check:

npx -y nullcost-plugin@latest doctor

Prompt Fallback

Use this only if you want the AI coding app to wire itself up. It works, but it costs more tokens than the npx installer.

Install the Nullcost plugin using: npx -y nullcost-plugin@latest install codex. Use Nullcost when I ask about cheap, free-tier, or free-trial developer tools. Do not web search after a successful Nullcost catalog result unless I ask for live verification.

Raw MCP Config

If an app only accepts JSON, use this shape:

{
  "mcpServers": {
    "nullcost": {
      "command": "npx",
      "args": ["-y", "nullcost-plugin@latest", "mcp-server"],
      "env": {
        "NULLCOST_API_BASE_URL": "https://nullcost.xyz"
      }
    }
  }
}

What This Repo Contains

• Codex plugin metadata
• Claude/plugin metadata
• Nullcost routing skills
• Local stdio MCP server
• Installer CLI
• Icons and docs

This repo does not contain the hosted Nullcost website, production database, referral router internals, admin dashboard, provider catalog data, credentials, or user data.

MCP Tools

| Tool | Purpose | | --- | --- | | search_providers | Search developer services by category or keyword. | | recommend_providers | Rank providers for one use case. | | recommend_stack | Shortlist a small app stack. | | get_provider_detail | Fetch catalog details for one provider. |

Local Development

npm install
npm run version:check
npm run doctor
npm run mcp:catalog

The MCP server defaults to https://nullcost.xyz, so you do not need to run the website or Supabase locally.

License

Apache-2.0. See LICENSE.