Mod Note: Most of the AI scripting community has migrated to Discord and the AI Scripters Forums. You will be more likely to get your questions answered there.

I will update this as I come up with ideas.

Question: "What does A.I. stand for?"
Answer:Artificial Intelligence.

Question: "How do I use AIs?"
Answer: you simply install them into the "AI" folder and look for the drop down list (normally titled "computer", click on it) when starting a single player game/skirmish.

Question: "What do I write AIs in?"
Answer:Notepad is fine, any text editor is fine. Be warned though, if the text editor encodes the text using hidden sybols, you will get an error in game that you cannot solve. Notepad never inserts these and therefore is the wisest choice.

Question: "How do I write AIs?"
Answer:On your installation cd there is a text file titled "CPSB". It contains all the available commands and parameters. If you have any questions, please post in the correct topic. (I warn you that there are some "strategic numbers" that are known not to work. I will post these and most likely have them stickied.)

Question: "Why won't my custom AI show up on the list?"
Answer:You must have two files for a custom AI to show up on the list of oppenents. Both files must have the exact same name, the exception will be in their extensions. One must have ".ai" (I recommend putting notes or nothing in here) and one must have ".per", this is where the code goes. Most AI's however are designed to use the first ".per" file to load other ".per" file

Example:
(load "MyNewAIFolder/TrainingList")
Syntax: (load ""foldername"/"filename"")

Question: "What is a rule?"
Answer: A rule is the basic back bone of AIs. A rule will be in the form of:

(defrule
(conditions)
=>
(actions)
)

Example:

(defrule
(game-time > 30) ;in seconds
=>
(chat-to-all "30 second mark!")
)

Question: "What is "defrule"?"
Answer:It's a simple rule starter and short for define-rule.

Question: "What's with the parenthesis at the end?"
Answer:You mean:
Example:

(defrule
(conditions)
=>
(actions)
) ;<---Here?

it is what ends a rule

Question: "How do I use "or"?"
Answer:"or" means if this OR this condition is true, than continue.
Syntax:
(or
(condition 1)
(condition 2)
)

Example:

(defrule
(or ;<---- This is the "or" starter
(game-time > 30) ;this is in seconds
(civilian-population > 2)
) ;<--- This is the "or" ender.
=>
(chat-to-all "Game started!")
)

Question: "Why is there a semicolon?"
Answer:It is to mark the presence of an author's comment. So the AI compiler/reader won't try to read it as an executable line in the rule.

Question: "Can I smush the parenthesis together?"
Answer: If that's what you are comfortable with. Make sure your ending and beginning parenthesis are where they need to be. Using the last example...
Example:

(defrule
(or(game-time > 30)
(civilian-population > 2))
=>
(chat-to-all "Game Started!"))

Question: "Can I write the lines side by side?"
Answer:Again, if that's what you are comfortable with, using the last example:

(defrule(or(gametime > 30)(civilian-population > 2))=>(chat-to-all "Game Started!"))

The "AI reader" will still read it the same way

Question: "How do I use "and"?"
Answer: This is another logical operator just like "or".
Syntax:
(and
(condition 1)
(condition 2)
)

Example:

(defrule
(or(game-time > 60)
(and(game-time > 30)
(civilian-population > 2)))
=>
(chat-to-all "Game Started!"))

Question: "What if I want more than two conditions under "or" or "and"?"
Answer:You can stack them, please view my example with heavy attention.
Example:

(defrule
(or(game-time > 30)
   (or
     (civilian-population > 2)
     (military-population > 1)
    )
)
=>
(chat-to-all "Game started!")
)

-to place this example in syntax only, it will look like this:

(defrule
(or(condition 1)
(or <---- as "condition 2"
(condition 1)
(condition 2)
) <--- end the second "or"
) <--- end the first "or"

You can even compress that to:

(defrule
(or(game-time > 30)
(or(civilian-population > 2)
(military-population > 1)))
=>
(chat-to-all "Game started!")
)

Question: "How do I make sure certain conditions are excluded?"
Answer:Say for example, you want to keep your town safe and don't want to attack if your town is under attack. There is a condition that can detect this. "(town-under-attack)". This is where the "not" condition comes into play.

Example:
;Say this would normally be your attack code.

(defrule
(military-population > 10)
(players-military-population any-enemy < 10)
=>
(attack-now)
)

;here it is using the "not" condition
;syntax is (not (condition 1))

(defrule
(not(town-under-attack)) ;force this condition to be only excluded
(military-population > 10)
(players-military-population any-enemy < 10)
=>
(attack-now)
)

Question: "Is there a version of "not" that can include more than one condition?"
Answer:Yes, this is called "nor" (neither this nor this)
Syntax:
(nor
(condition 1)
(condition 2)
)

Example:

(defrule
(nor(town-under-attack)
(game-time < 600)) ;5min is 600 seconds
(military-population > 10)
(players-military-population any-enemy < 10)
=>
(attack-now)
)

Question: "What are constants?"
Answer:Constants are user defined number constants. Constants are loaded only once in the game and can never change in value (non-goals). ALL CONSTANTS MUST BE AT THE HEAD OF THE SCRIPT!!!
Syntax:
(defconst "user definition" "value")

Example:
(defconst MaxFeudalVillagers 35)
;defconst stands for "define constant"

Question: "Why use constants?"
Answer: Say you set this 50 times in the script in different rules using this amount of villagers as a condition but, just using the number "35". Ask yourself what you would do if you needed to replace this number in every single rule? Try the replace-all function? No, you'd have to go through the whole script looking for it and changing it yourself. With constants, all you do is have to change the number in the defined constant.

Question: "What are all the symbols you can use in constants?"
Answer:Any casing of letters, symbols (on the keyboard, i.e. the "$" sign), or numbers. You cannot have spaces in the definition, example:
(defconst this number 35)

The compiler will just give you an error or a major bug. If needed you can just use the "_" symbol. Example:
(defconst this_number 35)

Question: "What are goals and how do I use them?"
Answer:Goals are variables that can save any value. Goals can be used as conditions and actions.
goal action syntax:
(set-goal "goal number" "value")
goal condition syntax:
(goal "goal number" "value")
Example:

(defrule
(condition)
=>
(set-goal 1 1) ;sets goal "1" to value "1"
)

(defrule
(goal 1 1); any other value in goal "1" will be ignored in this rule
=>
(action)
)

Or another prime example:
(defconst Attack_now 1)
(defconst YES 1)
(defconst NO 2)

(defrule
(condition)
=>
(set-goal Attack_now YES); compiler reads this as set goal "1" to value "1"
)

(defrule
(goal Attack_now YES); compiler reads this as "if goal "1" is set to "1"" do...
=>
(attack-now)
)

Goal numbers can only range from 1-70 per AI, anything above "70" will not save the value you assign it. Goal values can range from -32,000 and 32,000... the standard short integer I believe.

Question: "What are strategic numbers?"
Answer:Strategic numbers are goals that effect the AI's behavior directly. Example: "sn-camp-max-distance". This strategic number controls how far the AI is allowed to build a lumber-camp/mining-camp. The strategic number has a conditional and action syntax, they are as follows.
Strategic number conditionally: (strategic-number "strategic number title" "value compare symbol" "value")-The value compare symbol are "<,>,=,<=,>=" signs.

Example:

(defrule
[b](strategic-number sn-max-camp-distance < 10)[/b]
=>
(set-strategic-number sn-max-camp-distance 10)
)

Strategic number action: (set-strategic-number "strategic number title" "value")

Example:

(defrule
(strategic-number sn-max-camp-distance < 10)
=>
[b](set-strategic-number sn-max-camp-distance 10)[/b]
)

Question: "Is it possible to get the AI to direct its attacks towards a specific sort of building?"
Answer:This only works well with monasteries and wonders. You can find a good definition of this strategic number in the CPSB.

Example:

(defrule
(players-building-type-count any-enemy wonder > 0)
=>
(set-strategic-number sn-special-attack-type1 wonder)
(set-strategic-number sn-special-attack-influence1 100)
)

(defrule
(enemy-captured-relics)
=>
(set-strategic-number sn-special-attack-type1 monastery)
(set-strategic-number sn-special-attack-influence1 100)
)

Question: "How many goals you can use in a single script? How many timers? How many rules?"
Answer: You can manage 40 goals numbered 1 to 40, 10 timers numbered 1 to 10 and only 999 rules. Conditional loads allows you to use more rules since some of them are not loaded by the game engine at the game start.
An example of a conditional load is:

#load-if-defined JAPANESE-CIV
(defrule
(game-time > 0)
=>
(chat-to-all "Konnichiwa, I am japanese")
(disable-self);this rule cycles once and once only
#end-if

Question: "How do I use timers?"
Answer: Timer are pretty simple, if you know how to use them. This code shows a simple usage of a timer, for training a villager every 15 seconds.

(defconst VillControltimer 10)

(defrule
(true)
=>
(enable-timer VillControlTimer 1)
(disable-self)
)

(defrule
(unit-type-count-total villager < 100)
(or
(building-type-count town-center == 1)
(timer-triggered VillControltimer)
)
(can-train villager)
=>
(train villager)
(disable-timer VillControltimer)
(enable-timer VillControlTimer 15)
)

Question: "My AI sometimes doesn't build docks, Why?"
Answer: In certain situations the AI is unable to build docks: in maps with ice (including Norse Lands!), in nomad maps and in all maps in which AI start the game without a town center.

Question: "Why does my AI have idle villagers on the map?"
Answer: There are few reasons for which an AI may have idle villagers. All villagers over the 100th will be idle. If the sum of sn-food-gather-percentage, wood, gold and stone percentages is less than 100, you may see idle villagers, and naturally if all resourches are finished villagers will be idle. Also, check that your sn-maximum-wood-drop-distance, sn-maximum-food-drop-distance, sn-maximum-gold-drop-distance and sn-maximum-stone-drop-distance are set adequately high. Also, if you have sn-number-forward-builders or sn-initial-exploration-required set to anything other than zero, that can/will be a problem.

Question: "How large can a single rule be?"
Answer: If a rule is too big the game will give you an error message. Remember that a single rule can contain up to 16 "elements". Elements are facts, actions and conditions: "or", "not", "and" and such. so the following rules contains 8 elements

(defrule
(current-age >= feudal-age)
(or
(building-type-count farm < 10)
(idle-farm-count >= 2)
)
(not(town-under-attack))
(can-build farm)
=>
(build farm)
)

[This message has been edited by Leif Ericson (edited 08-19-2020 @ 02:59 PM).]