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AI · April 2, 2026

Open-agent-SDK – Claude Code's internals, extracted and open-sourced

Claude Code's source map leaked last month. Instead of just reading it, I fed the entire source into Claude Code itself and asked it to extract the core agent loop logic. The result: open-agent-sdk — a drop-in replacement for claude-agent-sdk that's fully open source and doesn't spawn a CLI subprocess. Why this matters if you've built with claude-agent-sdk: claude-agent-sdk is just a thin wrapper around the Claude Code binary. It works, but it's a black box — when something breaks, you're stuck. Every query creates a new Claude Code process. That's fine on a laptop, not fine when you're…

Open-agent-SDK – Claude Code's internals, extracted and open-sourced launched on April 2, 2026 with 7 votes, #1,538 of 21,248 launches that month and more than 75% of that year's launches.

Visit github.com ↗Alternativestop 7% of April 2026

What it does

Agent-SDK without CLI dependencies, as an alternative to claude-agent-sdk, completely open source - codeany-ai/open-agent-sdk-typescript

In the maker’s words, at launch

Claude Code's source map leaked last month. Instead of just reading it, I fed the entire source into Claude Code itself and asked it to extract the core agent loop logic. The result: open-agent-sdk — a drop-in replacement for claude-agent-sdk that's fully open source and doesn't spawn a CLI subprocess. Why this…

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