The inverse of the inbound webhook platform: hooks.outbound in
config.yaml lists HTTP targets + the plugin-hook events they subscribe
to (on_session_end, subagent_stop, post_tool_call, ...). Each firing
POSTs a JSON payload (same top-level shape as shell hooks' stdin wire)
signed GitHub-style with HMAC-SHA256 (X-Hermes-Signature-256).
Rides the existing hook bus — notify-only callbacks registered on the
plugin manager at the same CLI/gateway/main entry points as shell
hooks. Delivery is fire-and-forget via a bounded queue + single daemon
worker thread, so a dead endpoint can never stall a tool call. Bounded
retries (5xx/conn errors once; 4xx never). secret_env preferred over
inline secret. HERMES_SAFE_MODE skips registration. hermes hooks list
shows outbound targets with signed/UNSIGNED status.
Zero new model tools, zero new subsystems.