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 v2.1.259 ·

MCP allowedMcpServers check bypassed for non-plugin, non-env-expanded project scope

Project-scoped MCP servers that aren't from a plugin or env expansion now skip the allowlist check entirely.

TierUnder the hoodhow much it should matter to you
Useful2my rating, 1 to 5
Signal2worth watching, 1 to 5
AreaMCPwhat it touches
KindInternal Changesin v2.1.259,
Under the hood

Project-scoped MCP servers that aren't from a plugin or env expansion now skip the allowlist check entirely.

The allowedMcpServers restriction check now short-circuits to 'allowed' for servers whose scope is a project scope and which were not expanded from an environment variable or sourced from a plugin, skipping the full allowlist matching logic in that case.

Read from
Names in the bundleallowedMcpServers
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 Control MCP server access for your organization touched a line naming allowedMcpServers after this was published. * [Server-managed settings](/docs/en/server-managed-settings): deliver `allowedMcpServers` and `deniedMcpServers` from the claude.ai admin console managed-mcp see the edit
Confirmed since Anthropic's documentation has since written up allowedMcpServers, on All settings. | Restriction allowlists | Takes the list whole from the highest source that sets it, without adding entries from lower sources. When the highest source doesn't set one, takes it whole from the next source down | [`availableModels`](#avail… settings-reference see the edit
How sure we are
Two sources agreeTwo things we can check say the same as this entry.
Anthropic's documentation agreesAnthropic's documentation has since written up allowedMcpServers, on All settings.
Anthropic's release notes agreeChanged allowedMcpServers to govern only servers users add: a literal managed-mcp.json server your allowlist used to filter out now loads on…

See this entry in the whole of v2.1.259 →