CLAUDE_CODE_CLIENT_KEY_PASSPHRASE
A Claude Code environment variable, read out of the shipped bundle. It was in the build from v2.1.138 and was gone by v2.1.242.
What it is
Passphrase for encrypted CLAUDE\_CODE\_CLIENT\_KEY (optional)
Anthropic's own wording. Read off Environment variables, captured 2026-08-28.
Presence across releases
| Releases | Reading | Declared type | Default |
|---|---|---|---|
| 2.1.245 – 2.1.250 5 releases | never mined | — | — |
| 2.1.242 – 2.1.243 2 releases | not in the build | — | — |
| 2.1.160 – 2.1.241 73 releases | in the build | str | — |
| 2.1.138 – 2.1.159 20 releases | in the build | — | — |
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.
Changelog entries naming it
-
v2.1.232Password-protected client keys for mTLS
Set
CLAUDE_CODE_CLIENT_KEY_PASSPHRASEso an encrypted client key file works for mutual TLS.named in this entry
Documentation pages
- Environment variables reference table Claude Code CLI
- Monitoring mentions it Claude Code CLI
- Enterprise network configuration mentions it Claude Code CLI
A reference table page is one whose own table defines this name, and it is where the description above came from. A page that mentions it carries the name somewhere in its text and may say nothing about it at all. Every page carrying it.
Names beside it
Every environment variable in the inventory starting claude_code_client_key, 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.