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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

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One change

Give Claude custom tools

agent-sdk/custom-tools

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Nearest release: v2.1.233, published 20 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/custom-tools Changed · +2 / -2 lines

from line 315
 
 ### Configure allowed tools
 
-The `tools` option and the allowed/disallowed lists affect two layers: availability, which controls whether a tool appears in Claude's context, and permission, which controls whether a call is approved once Claude attempts it. `tools` and bare-name `disallowedTools` entries change availability. `allowedTools` and scoped `disallowedTools` rules change permission only.
+The `tools` option and the allowed/disallowed lists affect two layers: availability, which controls whether a tool appears in Claude's context, and permission, which controls whether a call is approved once Claude attempts it. `tools` and bare-name `disallowedTools` entries change availability. `allowedTools` and scoped `disallowedTools` rules change permission. If you name one of the [task-tracking tools](/docs/en/agent-sdk/todo-tracking#model-availability) in `allowedTools`, Claude Code also opts the session in.
 
 | Option                    | Layer        | Effect                                                                                                                                                                                                          |
 | :------------------------ | :----------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | `tools: ["Read", "Grep"]` | Availability | Only the listed built-ins are in Claude's context. Unlisted built-ins are removed. MCP tools are unaffected.                                                                                                    |
 | `tools: []`               | Availability | All built-ins are removed. Claude can only use your MCP tools.                                                                                                                                                  |
-| allowed tools             | Permission   | Listed tools run without a permission prompt. Unlisted tools remain available; calls go through the [permission flow](/docs/en/agent-sdk/permissions).                                                               |
+| allowed tools             | Permission   | Listed tools run without a permission prompt. Other unlisted tools remain available; calls go through the [permission flow](/docs/en/agent-sdk/permissions).                                                         |
 | disallowed tools          | Both         | A bare tool name such as `"Bash"` removes the tool from Claude's context, the same as omitting it from `tools`. A scoped rule such as `"Bash(rm *)"` leaves the tool in context and denies only matching calls. |
 
 To remove a built-in entirely, omit it from `tools` or list its bare name in `disallowedTools` (Python: `disallowed_tools`); both keep the tool out of context so Claude never attempts it. A scoped `disallowedTools` rule blocks matching calls but leaves the tool visible, so Claude may waste a turn trying it. See [Configure permissions](/docs/en/agent-sdk/permissions) for the full evaluation order.