Claude Agent SDK
anthropics/claude-agent-sdk-python
The SDK behind Claude Code, exposed for building your own agents.
Anthropic's Agent SDK packages the harness that powers Claude Code — the tool-use loop, subagents, context management, MCP support and hooks — so developers can build the same class of coding and task agents on top of Claude models.
In the news
Anthropic launches the Claude Agent SDK
Anthropic open-sources the SDK behind Claude Code — the agent loop, tool use, subagents, memory and hooks — letting developers build their own Claude-powered agents on production rails.
Anthropic blocks third-party use of Claude Code subscriptions
Anthropic began enforcing its terms against third-party clients using Claude Code subscriptions, forcing alternative harnesses like opencode to rework authentication (its issue thread became the debate's ground zero). A defining platform-risk moment for the open-harness ecosystem: the model provider owns the login, the harness does not.
Anthropic moves MCP toward open foundation governance
Anthropic announces plans to donate MCP to a neutral foundation, with new registry, auth and sandbox specs — cementing MCP as vendor-neutral infrastructure for the entire agent ecosystem.
Claude Code hits GA; Anthropic hosts 'Code with Claude'
Anthropic makes Claude Code generally available and holds its first developer conference — with Claude Code for web, enterprise features, and hooks/MCP improvements central to agent workflows.
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superpowers
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