tengu_mcp_discovery_cache_enable
A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.238, including the newest one read.
What it is
Calling a tool on a disabled MCP server would tell you to re-enable it, but that path is off.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.238.
Presence across releases
| Releases | Reading | Declared type | Default |
|---|---|---|---|
| 2.1.245 – 2.1.250 5 releases | never mined | — | — |
| 2.1.238 – 2.1.243 6 releases | in the build | — | null |
A row reading never mined is a release with no archived bundle behind it. Nothing was read out of it, so nothing here says whether the name was in it. A declared type or a default is only ever what that release's own bundle stated.
Gate readings
| Release | Resolved | This account | Anonymous | Compiled default |
|---|---|---|---|---|
| v2.1.238 | Not enough to say | no value returned | no value returned | not a boolean we can read |
Two arms, because they disagree: this account is the one account this site reads and anonymous is a baseline with no identity attached. A reading says nothing about your account, and off cannot rule out a rollout both readings sit outside of. What these readings can and cannot show.
Changelog entries naming it
-
v2.1.238Calling a tool on a disabled MCP server errors instead of quietly reconnecting
Calling a tool on a disabled MCP server would tell you to re-enable it, but that path is off.
gate cited by this entry
-
v2.1.238The MCP discovery cache is now off unless explicitly turned on
The MCP discovery cache flipped from on-by-default to off unless the server or you enable it.
gate cited by this entry
-
v2.1.238MCP work aborts when the signed-in account changes mid-flight
Switching accounts would cancel in-flight MCP work instead of finishing it under the new identity, but it's dark.
gate cited by this entry
Documentation pages
None of Anthropic's documentation pages this site has a copy of carries this name.
Names beside it
Every feature flag in the inventory starting tengu_mcp_discovery_cache, up to twelve of them.
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the feature flag does. All feature flags.