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Sweep 28 Aug 2026 ยท 00:00Z Build v2.1.250 478 read Stable v2.1.236 Latest v2.1.250 Next v2.1.250 Feeds RSS JSON llms.txt

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

One change

Subagents in the SDK

agent-sdk/subagents

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Nearest release: v2.1.235, published 4 hours before this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.

agent-sdk/subagents Changed · +2 / -0 lines

from line 188
 
 <Note>
   Even without defining custom subagents, Claude can spawn the built-in `general-purpose` subagent. This is useful for delegating research or exploration tasks without creating specialized agents. Include `Agent` in `allowedTools` so these invocations auto-approve without a permission prompt.
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+  A call to the Agent tool that leaves out `subagent_type` gets this built-in `general-purpose` subagent. If you disable the built-in subagents with [`CLAUDE_AGENT_SDK_DISABLE_BUILTIN_AGENTS=1`](/docs/en/env-vars), there is nothing to fall back to. Such a call then fails with `subagent_type is required: the general-purpose agent is not available in this session`, followed by the names of your subagents. Before TypeScript SDK v0.3.235 (Python SDK: bundled Claude Code earlier than v2.1.235), it failed with `Agent type 'general-purpose' not found` instead.
 </Note>
 
 ## What subagents inherit