Treat stdio server env variables as secrets like HTTP headers - #342
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A config entry's `env` routinely holds API tokens — directly or via `${VAR}`
substitution — but only `headers` were protected. Resolved `env` values were
written to `sessions.json` in plaintext, printed verbatim by `mcpc --json
@session` / `connect --json`, and passed to the bridge in its command line,
where `ps` exposed them.
They now follow the exact same path as headers: stored in the OS keychain
(`session:<name>:env`), redacted to `<redacted>` in `sessions.json` and all
`--json` output, and delivered to the bridge over IPC after spawn. The bridge
merges them back into the stdio transport config, so servers still get their
environment unchanged. Sessions written before this change keep working —
their on-disk plaintext is used as is; recreate a session to move its values
into the keychain.
Rebuilt on main after the draft branch was squashed in as #316.
Fixes #341
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Rmdd458q2Bx68bPxuUtQGa
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A stdio server's
envroutinely holds API tokens (directly or via${VAR}substitution), but onlyheaderswere protected. Resolvedenvvalues were written tosessions.jsonin plaintext, printed verbatim bymcpc --json @session, and — not in the issue but worse — passed in the bridge's command line, wherepsexposed them. They now follow the exact same path as headers.session:{name}:env), removed with the sessionsessions.jsonand every--jsonoutput (documented in the help and docs/REFERENCE.md)stdio/env-securitye2e suite proves the secret is absent fromps,sessions.json, both--jsonshapes, the bridge log and verbose output, while anecho-envtool confirms it still reaches the serverFixes #341
https://claude.ai/code/session_01Rmdd458q2Bx68bPxuUtQGa