docs(gateway): document exact silence tokens (#46105)

website/docs/user-guide/features/cron.md

@@ -300,7 +300,7 @@ cron:
 
 ### Silent suppression
 
-If the agent's final response starts with `[SILENT]`, delivery is suppressed entirely. The output is still saved locally for audit (in `~/.hermes/cron/output/`), but no message is sent to the delivery target.
+If the agent's final response contains `[SILENT]`, delivery is suppressed entirely. The output is still saved locally for audit (in `~/.hermes/cron/output/`), but no message is sent to the delivery target.
 
 This is useful for monitoring jobs that should only report when something is wrong:
 
@@ -309,7 +309,7 @@ Check if nginx is running. If everything is healthy, respond with only [SILENT].
 Otherwise, report the issue.
 ```
 
-Failed jobs always deliver regardless of the `[SILENT]` marker — only successful runs can be silenced.
+Failed jobs always deliver regardless of the `[SILENT]` marker — only successful runs can be silenced. For quiet monitoring jobs, prompt the agent to reply with only `[SILENT]` when there is nothing to report.
 
 ## Script timeout
 

website/docs/user-guide/features/hooks.md

@@ -274,8 +274,8 @@ def _run_boot_agent(content: str) -> None:
             max_iterations=20,
         )
         result = agent.run_conversation(_build_prompt(content))
-        response = result.get("final_response", "")
-        if response and "[SILENT]" not in response:
+        response = (result.get("final_response", "") or "").strip()
+        if response.upper() not in {"[SILENT]", "SILENT", "NO_REPLY", "NO REPLY"}:
             logger.info("boot-md completed: %s", response[:200])
         else:
             logger.info("boot-md completed (nothing to report)")
@@ -323,7 +323,7 @@ Watch the logs:
 hermes logs --follow --level INFO | grep boot-md
 ```
 
-You should see `Running BOOT.md (N chars)` followed by either `boot-md completed: ...` (summary of what the agent did) or `boot-md completed (nothing to report)` when the agent replied `[SILENT]`.
+You should see `Running BOOT.md (N chars)` followed by either `boot-md completed: ...` (summary of what the agent did) or `boot-md completed (nothing to report)` when the agent replied with an exact silence token such as `[SILENT]`.
 
 Delete `~/.hermes/BOOT.md` to disable the checklist — the hook stays loaded but silently skips when the file isn't there.