docs: document config.json and notifyctl reload

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/README.md b/README.md
index b7ef38d..f2f7cef 100644
--- a/README.md
+++ b/README.md
@@ -31,6 +31,25 @@ dunst is not removed until this proves itself. To switch:
 The renderer that draws the balloons is a separate plan; until it ships the
 queue is visible through `notifyctl list`.
 
+## Configuration
+
+`~/.config/notifyd/config.json` (`$XDG_CONFIG_HOME` is honoured). Every key
+is optional and the defaults are the behaviour without the file:
+
+    {
+      "timeouts": { "low": 10, "normal": 10, "critical": 0 },
+      "liveCap": 20,
+      "historyCap": 20
+    }
+
+Timeouts are seconds, 0 is never, and apply only when a client sends
+`expire_timeout -1`. Caps clamp to 1..100; a lowered cap applies at the next
+notification. A broken file is logged and read as the defaults.
+
+The daemon reads it at start and on `notifyctl reload`. The quickshell
+settings page writes it; the same file carries the balloon shell's keys
+(`balloons`, `dndPassCritical`, `muted`), which the daemon ignores.
+
 ## License
 
 GPLv2 only. See [LICENSE](LICENSE).