GET /workspaces/:id/files/config.yaml on hongming.moleculesai.app's
Hermes workspace returned 500 with body:
ssh cat: exit status 1 (Warning: Permanently added '[127.0.0.1]:37951'
(ED25519) to the list of known hosts.)
Root cause: ssh emits the "Permanently added" notice on every fresh
tunnel connection, even with UserKnownHostsFile=/dev/null (that
prevents persistence, not the warning). It lands on stderr, fooling
readFileViaEIC's classifier:
if len(out) == 0 && stderr.Len() == 0 {
return nil, os.ErrNotExist
}
return nil, fmt.Errorf("ssh cat: %w (%s)", runErr, ...)
stderr was non-empty (the warning), so we returned the wrapped error
→ 500 from the HTTP layer instead of 404.
Fix: add `-o LogLevel=ERROR` to BOTH writeFileViaEIC and readFileViaEIC
ssh invocations. Silences info+warning while keeping real auth/tunnel
errors visible (those emit at ERROR level).
Test: TestSSHArgs_LogLevelErrorBothSites pins the flag in both blocks.
Mutation-tested: stripping the flag from one site fails the gate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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