What it is
Two new env vars were added to internal forwarding and auth-token handling lists.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.260.
Presence across releases
1Build by build
17One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
First cited
0No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.
Names beside it
Every environment variable in the inventory starting claude_code_forward, 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 environment variable does. All environment variables.