CodeSampleX (CSX) is a free upgrade pack for AI coding agents, providing an execution memory of package versions, APIs, and environments that have been tested in practice. Rather than relying on documentation or plausible guesses, it helps agents recall recorded successes and failures for specific package and runtime combinations before writing code. Its evidence covers build-stage observations and distinguishes whether a sample exists from how it performed in a particular environment. Users can explore compatibility data, search for samples that built and passed their contracts, and inspect detailed failure information or verification receipts when needed.

The CSX command-line interface can wrap builds and tests to record anonymous evidence, scan projects to identify public package usage without building, and provide local statistics. It also connects with coding agents, including Claude Code, Codex, Gemini CLI, Antigravity, and OpenCode; other clients can be configured manually. Community mode shares sanitized facts about public packages, versions, symbols, environments, and build results, not source code or raw logs.