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Sweep 22 Oct 2026 · 04:32Z Build v2.1.308 527 read Stable v2.1.308 Latest v2.1.308 Next v2.1.308 Feeds RSS JSON llms.txt llms-full.txt Unofficial
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Claude Code v2.1.299 ·

Cloud and headless runs can list tools to block

The configuration for cloud and headless runs now accepts an optional disallowed_tools list next to allowed_tools

Use it now Improvements
JSON All of v2.1.299
Use it nowTier: how much it should matter to you
3Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
Headless ModeArea: what it touches
ImprovementsKind: in v2.1.299,
What probably matters to youSection of the release

Unclear Whether Claude Code actually blocks the tools named in disallowed_tools is not shown, only that the setting is accepted.

What

The configuration used for cloud and headless runs (sessions that run without you typing into a terminal) already accepted timeout_seconds and allowed_tools. It now also accepts disallowed_tools, an optional list of tool names. Tools are the actions Claude can take, such as reading files or running commands.

Why

A request to start one of these runs can now name tools to deny outright, rather than only listing the tools that are allowed.

Read from
Names in the bundledisallowed_toolsallowed_toolstimeout_seconds
Since it was published

The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.

Added since A small documentation edit on Configure permissions touched a line naming allowed_tools after this was published. Allow rules accept tool-name globs only after a literal `mcp__<server>__` prefix. The server segment must be glob-free so the rule names a specific server you configured: `mcp__puppeteer__*` matches every tool from the `puppeteer` server, … agent-sdk/permissions see the edit
Confirmed since Anthropic's documentation has since written up timeout_seconds, on self-hosted-sandboxes-custom-tools. read, write, read_timeout_seconds=timedelta(seconds=60) managed-agents/self-hosted-sandboxes-custom-tools see the edit
Confirmed since Anthropic's documentation has since written up allowed_tools, on Subagents in the SDK. disallowed_tools=["Agent(fork)"], agent-sdk/subagents see the edit
Confirmed since Anthropic's documentation has since written up disallowed_tools, on Subagents in the SDK. disallowed_tools=["Agent(fork)"], agent-sdk/subagents see the edit
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtWhether Claude Code actually blocks the tools named in `disallowed_tools` is not shown, only that the setting is accepted.
Anthropic's documentation agreesAnthropic's documentation has since written up disallowed_tools, on Subagents in the SDK.
Anthropic's release notes agreeAdded --disallow-tools and a disallowed_tools case field to claude plugin eval to keep specific built-in tools, such as Agent, out of eval…

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