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Co-authored-by: Wez Furlong <[email protected]>

docs/config/lua/wezterm/to_string.md

@@ -10,6 +10,14 @@ tags:
 This function returns a string representation of any Lua value. In particular
 this can be used to get a string representation of a table or userdata.
 
+The intended purpose is as a human readable way to inspect lua values.  It is not machine
+readable; do not attempt to use it as a serialization format as the format is not guaranteed
+to remain the same across different versions of wezterm.
+
+This same representation is used in the [debug overlay](../keyassignment/ShowDebugOverlay.md
+when printing the result of an expression from the Lua REPL and for the implicit string
+conversions of the parameters passed to [wezterm.log_info](log_info.md).
+
 ```lua
 local wezterm = require 'wezterm'
 assert(wezterm.to_string { 1, 2 } == [=[[