Follow Discord
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
HomeReleasesv2.1.248entry #17

Claude Code v2.1.248 ·

MCP server allow and deny lists get settings keys

You can allow or block specific MCP servers with allowedMcpServers and deniedMcpServers settings.

Use it now Notable Internal Changes
JSON All of v2.1.248
Use it nowTier: how much it should matter to you
4Useful: my rating, 1 to 5
4Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.248,
What probably matters to youSection of the release
What

Two settings keys, allowedMcpServers and deniedMcpServers, are now paired with validation schemas in a table, so MCP servers can be permitted or blocked from settings files.

Details
  • New arrays group the settings tiers: policySettings, flagSettings and userSettings on one side, localSettings and projectSettings on the other, with a map labelling the first three policy, flag and user.
  • A separate map ties the decisions allow, deny and ask to the rule lists alwaysAllowRules, alwaysDenyRules and alwaysAskRules.
Evidence

{ key: "allowedMcpServers", schema: tzt }

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Read from
Names in the bundleallowedMcpServersdeniedMcpServers
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 deniedMcpServers 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
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 deniedMcpServers, on Claude Code changelog. * Fixed `allowManagedMcpServersOnly`, `deniedMcpServers` and `disableClaudeAiConnectors` set via MDM or `managed-settings.json` being ignored when server-managed settings are also present changelog 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
One source agreesOne thing we can check says the same as this entry.
Anthropic's documentation agreesAnthropic's documentation has since written up allowedMcpServers, on All settings.

See this entry in the whole of v2.1.248 →

Feedback