OpenTTD AI suitability list

This list is not officially sanctioned, it is a players opinion from tests and not connected to OpenTTD developers.
All AI's were tested on a 1028x1028 map, with no GRF's. Your mileage may vary if you use GRF's, especially those that change industries or vehicles. Some AI react badly to oddly shaped maps, or maps that are tiny or excessively large.
At the bottom of the page are criteria used to measure AI's, click here to skip to bottom.

Stable, more than likely to operate fine in your game, also actively updated and any current issues are not pervasive.	Stable, but with some issues, also unupdated so fixes are not expected for anything at all. Also includes failed AI's that have a fix (which will be linked) by a different user.	Flat out not recommended due to crash issues, with no anticipated updates.

If you'd like to use an AI with a CPU error in valuator, Xarick has provided a fix here.
Last updated: December 2024

AI Name	Recommended	Notes	Link
AAAHogEx		-> Extremely competitive. By far the best for if you're trying to have a game where you outperform a challenger.	TT-Forums
AdmiralAI		-> May crash if you build a town whilst in game. A fix for this is by using this updated code by odisseus. -> Clones profitable vehicles endlessly, which may jam up a rail network until nothing can move.	TT-Forums
AIAI		-> Excess CPU violation error. -> Builds RV stops sometimes well outside of the town roads.	TT-Forums
BorkAI		-> Creates stations it never uses, or doesn't destroy them reliably after stopping using them.	TT-Forums
Chopper		-> Requires aircraft to not be set to 0, only builds helicopters.	TT-Forums
CivilAI		-> May crash with invalid type 'null' errors. -> No fixes or updates are expected, the author has declared it is dead.	TT-Forums
ChooChoo		-> Some of its track laying is hilarious. -> Clones profitable vehicles endlessly, which may jam up a rail network until nothing can move.	TT-Forums GitHub
CluelessPlus			TT-Forums
CoronaAI			TT-Forums GitHub
CPU		-> Poor performing, but functional without crashing. -> Leaves debug messages around, disable it from AI options before starting game. -> Uses road vehicles only.
Denver & Rio Grande		-> Excess CPU violation error	TT-Forums
DictatorAI		-> Excess CPU violation error.	TT-Forums
EmotionAI
EpicTrans		-> Creates stations it never uses, or doesn't destroy them reliably after stopping using them.
FastPTPAI		-> Excess CPU violation error.	TT-Forums
gelignAlte		-> Only builds minimal amount of stuff and makes little profit using RVs.	TT-Forums
HeliFerry		-> Builds excessive buoys. -> Blindly follows the coastline, even if there is a large estuary or similar which adds time to a journey that it wouldn't have had, had it gone straight ahead instead of around coastlines.	TT-Forums
LuDiAI		-> Doesn't check vehicle limits before building stations, so can have empty stations as it has no vehicles left in max allowed vehicles for each type (RVs, boats, aircraft etc), example. -> Index doesn't exist error.
LuDiAI AfterFix			TT-Forums
MailAI		-> If you run into lots of signs being made, a fix is available by Steffl on TT-Forums here.
MpAI		-> Crashes with index doesn't exist error.
Mungo		-> Aircraft only, will not work if you have max aircraft allowed to 0. -> Doen't handle save/load sequence, crashes with "GetLocation doesn't exist".	TT-Forums
NoCAB		-> Crashes with save error -> Sends all RV's to depot for some reason.
NoNoCAB			TT-Forums
NotPerfectAI		-> Sometimes builds road stops outside of the city grid.	TT-Forums
OtviAI		-> AI is confused by dual headed trains, and builds carriages up to max length setting, but gets stuck in a loop if its double headed and the second loco on the back goes over limit [example].
PathZilla		-> Crashes with "too long to save" error. A fix is available on TT-Forums here.	TT-Forums
PAXLink		-> Excess CPU violation error. -> Creates mass buses that may go a very short distance and lose money, often resulting in bankrupcy. -> Pays no respect to other roads users, if they get stuck within its mass swarm of RV's that lose money anyway, so be it.	TT-Forums
RailwAI		-> Sometimes edits its own network whilst trains are in the area, causing crashes.	TT-Forums
RoadRunner		-> Crashes with index 'pptile' does not exist.	TT-Forums
RoadAI		-> May fail to build anything at all with error of pathfinding taking too long.	TT-Forums
rocketAI		-> Builds a very basic amount of stuff, then terminates (crashes) itself.	TT-Forums
Rythorn Airline AI		-> Index doesn't exist error.	TT-Forums
SimpleAI
SmallTownAI		-> Crashes with expecting integer but given null errors.
Snake		-> Often builds arguably too many RV depots. -> Sometimes leaves remnants when cleaning up old routes. -> Performs better with higher max airplanes & road vehicles per user limits than default, if your machine can handle it, then worth doing.	TT-Forums
SuperSimpleAI			TT-Forums
ShipAI
SynTrans			TT-Forums
Terron			TT-Forums
TeshiNet		-> Crashes with invalid location.
TracAI		-> Excess CPU violation error. -> Index doesn't exist error.
TrAIns		-> Clones profitable vehicles endlessly, which may jam up a rail network until nothing can move. -> Creates stations it never uses, or doesn't destroy them reliably after stopping using them, usually rail ones
TransAI		-> Appears to build airports, but doesn't use them.
UberSwarm		-> Road vehicle only.
WrightAI		-> Instantly crashes if max airplanes is set to 0, only uses aircraft. -> Appears to essentially be a demo AI made by OTTD team with no further updates.	OpenTTD Wiki
WmDOT		-> Builds one way roads with no respect for stations or other RV's. [example]	TT-Forums
WormAI			TT-Forums

Criteria

• Any 'Error' -> This is a crash situation, the AI crashed & needed restarting, which wipes any current progress of the AI.
• 'Creates stations it never uses / doesn't destroy' -> At the end of at least one test period, the AI had at least 15 stations, of any type, without vehicles stopping at.
• 'Clones profitable vehicles endlessly' -> The AI created enough vehicles on the same route that it negatively affected itself, or worse, it totally jammed up a segment of railway or road.

Icons are from FlatIcon.