Free tools for agent builders

Small, free tools for people shipping with Claude Code, Cursor and Codex. Work out what a run cost, write a CLAUDE.md your agent will actually follow, and build an MCP config for any client. Each one runs in your browser; nothing you type is sent anywhere.

Claude Code cost calculator

Turn a run’s token counts into the API-equivalent cost, with cache reads priced right.
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CLAUDE.md & AGENTS.md generator

Answer a few questions and get a CLAUDE.md and AGENTS.md to copy into your repo.
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MCP config builder

Pick a popular MCP server, copy the config for Claude Code, Cursor, Codex or Claude Desktop.
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