client_assertion
A Claude Code settings key, read out of the shipped bundle. It has been in the build since v2.1.287, including the newest one read.
The gateway's OIDC config accepts private_key_jwt with a certificate in oidc.client_assertion, so oidc.client_secret is now optional
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.284.
In the changelogs
1Releases whose published page names client_assertion.
-
v2.1.284
Claude gateway can sign in to its identity provider with a certificate
The gateway's OIDC config accepts
private_key_jwtwith a certificate inoidc.client_assertion, sooidc.client_secretis now optionalfound in this entry's text
First cited
1The earliest release whose published evidence quoted client_assertion was v2.1.284, 28 Sep 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
Presence across releases
1Build by build
9One 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.
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 settings key does. All settings keys.