This article describes how to skip IDP inspection of a set of attacks in certain traffic.

The exempt rulebase is available to skip detection of a set of attacks in certain traffic.

Please find the detail in techlibrary document below.
Understanding IDP Exempt Rulebases

Following example is to skip HTTP:TOO-MANY-PARAMETERS inspection for 192.168.0.1.

Example:
*create address-book for trusted user IP subnet
set security address-book global address exempt-user 192.168.0.1/32

*create rulebase-exempt rule
set security idp idp-policy Recommended rulebase-exempt rule test-rule match source-address exempt-user
set security idp idp-policy Recommended rulebase-exempt rule test-rule match from-zone trust
set security idp idp-policy Recommended rulebase-exempt rule test-rule match attacks predefined-attacks HTTP:TOO-MANY-PARAMETERS
set security idp idp-policy Recommended rulebase-exempt rule test-rule then notification log-attacks alert

For rule match options, we have following options.
root# set security idp idp-policy Recommended rulebase-exempt rule root-user match ?
Possible completions:
+ apply-groups     Groups from which to inherit configuration data
+ apply-groups-except Don't inherit configuration data from these groups
> attacks       Match attack objects
+ destination-address Match destination address
+ destination-except  Don't match destination address
 from-zone      Match from zone
+ source-address    Match source address
+ source-except    Don't match source address
 to-zone       Match to zone