Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.271 ·

New 'strict' permission mode for permission-prompt tools (not yet reachable)

A stricter permission mode that rejects tool calls whose input was changed in disallowed ways is built but not yet wired up

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AreaSDK Permissionswhat it touches
KindIn Developmentin v2.1.271,
Group of 3 Nothing to try yet Notable

A stricter permission mode that rejects tool calls whose input was changed in disallowed ways is built but not yet wired up

What

  • The permission-prompt-tool flow was refactored to branch on a kind, with the existing behavior renamed "launcher" and a new "strict" path added. The kind is threaded through several internal functions, including createCanUseTool.
  • Under "strict", if a permission answer changed the tool's input in a way that isn't allowed, the tool call is hard-denied instead of running.
  • The sandbox's network-ask callback now takes this kind: "launcher" still applies broad, session-wide permission updates from an allowed network request, while "strict" instead applies only limited permission updates.
  • The PermissionRequest hook handler now validates, for "strict" kind, that a hook's updatedInput actually matches the original input, denying the call if it doesn't rather than silently accepting the change as before.

Why

This lays the groundwork for a tighter permission mode that can't be bypassed by a hook silently rewriting tool input, though the members indicate this "strict" path isn't reachable yet.

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 doubtThe finding shows the strict branch exists in code but does not show anything that selects or reaches it, so it is not yet active for any…

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