The Hermes installer printed "[OK] enabled plugin" and "Done!" while leaving agency-agents-router disabled or absent. On current Hermes this hit every user: the default plugins: block contains a column-0 "# ====" banner, and `hermes plugins enable/disable` writes enabled:/disabled: below it.
- Bound the enabled: sub-block at the first sibling key; sweep stale entries out of disabled: (Hermes: "an explicit disable wins"); handle inline [], [a,b], disabled: above enabled:, trailing comments, corrupted-scalar recovery; bail on shapes that can't be edited line-wise. (@guozi-lab)
- A column-0 comment no longer ends the plugins: block, and the rewrite's exit status propagates (`|| return 1`) so a bail warns instead of reporting success. (maintainer follow-up)
- check-hermes-config-rewrite.py: 16 cases, including Hermes' real shape.
Verified in real Hermes (official installer, 9a0a162) on configs Hermes wrote itself, with a live turn on local qwen3.8-27b: main -> "agency_agents_delegate does not exist"; this change -> delegated: true, real subagent, real result.
Closes#879
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
ensure_hermes_plugin_enabled() hardcoded a 2-space indent for the inserted `- agency-agents-router` line. Hermes writes plugins.enabled items at 4 spaces, so the new line and the next existing item collapsed into one plain scalar ("agency-agents-router - disk-cleanup") and every previously enabled plugin silently dropped (#839, and #689 diagnosed the same in July). The inserter now matches the existing item indent (default 4), appends after existing entries so order is preserved, and is idempotent on re-run. scripts/check-hermes-config-rewrite.{sh,py} runs seven regression cases; a small workflow runs it on every PR.
Reproduced on main with a 4-space config and verified fixed with this patch; installer suite 36/0; the regression script passes 7/7.
Fixes#839. Closes#689 (same fix, proposed first by @harshsinghmp).
Co-Authored-By: Harsh Singh <32476777+harshsinghmp@users.noreply.github.com>
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
