{"version":"2.1.300","anchor":"mcp-server-allowlist-check-can-use-a-new-flag-tengu-peppy-ri","canonical_anchor":"mcp-server-allowlist-check-can-use-a-new-flag-tengu-peppy-ri","heading":"An MCP server list check can now be answered by a single on\/off switch","tier":"internal","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.300\/e\/mcp-server-allowlist-check-can-use-a-new-flag-tengu-peppy-ri","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.300","markdown":"### An MCP server list check can now be answered by a single on\/off switch\n\nA check that matched MCP servers against a remote list can now read a single on\/off switch instead, depending on how it is called\n\n**Unclear.** What being on the list turns on for an MCP server is not stated.\n\n**What**\n\nMCP servers are outside programs that give Claude Code extra tools. Claude Code has a check that compares a server against a list supplied remotely. That check now takes an extra option. When the option is set, the check ignores the list and reads a single on\/off switch, `tengu_peppy_riddle`. It reports the switch's value as whether the server is listed.\n\nThe switch is off unless it is turned on remotely. The flag server has returned on for this site's account and for an anonymous check. When the extra option is not set, the check still uses the list as before.\n\n**Why**\n\nA feature that was turned on server by server can now be turned on for all servers at once, or for none.\n\n- Flag `tengu_peppy_riddle`: Off by default, switched on for this account (read for one account on one subscription tier against v2.1.300; this account: on, anonymous baseline: on, compiled default: off) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Flag `tengu_tender_truffle`: Not enough to say (read for one account on one subscription tier against v2.1.300; this account: no value returned, anonymous baseline: no value returned, compiled default: not a boolean we can read) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Area: MCP\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: no"}