Pokemon Showdown's protocol is relatively simple.
Pokemon Showdown is implemented in SockJS. SockJS is a compatibility layer over raw WebSocket, so you can actually connect to Pokemon Showdown directly using WebSocket:
ws://sim.smogon.com:8000/showdown/websocket
or
wss://sim.smogon.com/showdown/websocket
Client implementations you might want to look at for reference include:
- pickdenis' chat bot (Ruby) - https://github.com/pickdenis/ps-chatbot
- Quinella and TalkTakesTime's chat bot (Node.js) - https://github.com/TalkTakesTime/Pokemon-Showdown-Bot
- the official client (HTML5 + JavaScript) - https://github.com/Zarel/Pokemon-Showdown-Client
The official client logs protocol messages in the JavaScript console, so opening that (F12 in most browsers) can help tell you what's going on.
Messages from the user to the server are in the form:
ROOMID|TEXT
ROOMID
can optionally be left blank if it's the lobby, or if the room
is irrelevant (for instance, if TEXT
is a command like
/join lobby
where it doesn't matter what room it's sent from, you can
just send |/join lobby
.)
TEXT
can contain newlines, in which case it'll be treated the same
way as if each line were sent to the room separately.
A partial list of available commands can be found with /help
.
To log in, look at the documentation for the |challstr|
server message.
Messages from the server to the user are in the form:
>ROOMID
MESSAGE
MESSAGE
MESSAGE
...
>ROOMID
and the newline after it can be omitted if the room is lobby
or global. MESSAGE
cannot start with >
, so it's unambiguous whether
or not >ROOMID
has been omitted.
As for the payload: it's made of any number of blocks of data separated by newlines; empty lines should be ignored. In particular, it should be treated the same way whether or not it ends in a newline, and if the payload is empty, the entire message should be ignored.
If MESSAGE
doesn't start with |
, it should be shown directly in the
room's log. Otherwise, it will be in the form:
|TYPE|DATA
For example:
|j| Some dude
|c|@Moderator|hi!
|c| Some dude|you suck and i hate you!
Some dude was banned by Moderator.
|l| Some dude
|b|battle-ou-12| Cool guy|@Moderator
This might be displayed as:
Some dude joined.
@Moderator: hi!
Some dude: you suck and i hate you!
Some dude was banned by Moderator.
Some dude left.
OU battle started between Cool guy and Moderator
For bandwidth reasons, five of the message types - chat
, join
, leave
,
name
, and battle
- are sometimes abbreviated to c
, j
, l
, n
,
and b
respectively. All other message types are written out in full so they
should be easy to understand.
Four of these can be uppercase: J
, L
, N
, and B
, which are
the equivalent of their lowercase versions, but are recommended not to be
displayed inline because they happen too often. For instance, the main server
gets around 5 joins/leaves a second, and showing that inline with chat would
make it near-impossible to chat.
USER
= a user, the first character being their rank (users with no rank are
represented by a space), and the rest of the string being their username.
####Room initialization
|init|ROOMTYPE
The first message received from a room when you join it.
ROOMTYPE
is one of:chat
orbattle
|users|USERLIST
USERLIST
is a comma-separated list ofUSER
s, sent from chat rooms when they're joined.
####Room messages
||MESSAGE
or MESSAGE
We received a message
MESSAGE
, which should be displayed directly in the room's log.
|html|HTML
We received an HTML message, which should be sanitized and displayed directly in the room's log.
|join|USER
or |j|USER
USER
joined the room.
|leave|USER
or |l|USER
USER
left the room.
|name|USER|OLDID
or |n|USER|OLDID
A user changed name to
USER
, and their previous userid wasOLDID
.
|chat|USER|MESSAGE
or |c|USER|MESSAGE
USER
saidMESSAGE
. Note thatMESSAGE
can contain|
characters, so you can't just split by|
and take the fourth string.
|:|TIMESTAMP
|c:|TIMESTAMP|USER|MESSAGE
c:
is pretty much the same asc
, but also comes with a UNIX timestamp; (the number of seconds since 1970). This is used for accurate timestamps in chat logs.
:
is the current time according to the server, so that times can be adjusted and reported in the local time in the case of a discrepancy.The exact fate of this command is uncertain - it may or may not be replaced with a more generalized way to transmit timestamps at some point.
|battle|ROOMID|USER1|USER2
or |b|ROOMID|USER1|USER2
A battle started between
USER1
andUSER2
, and the battle room has IDROOMID
.
####Battle messages
|player|PLAYER|USERNAME|AVATAR
Appears when you join a battle room.
PLAYER
denotes which player it is (p1
orp2
) andUSERNAME
is the username.AVATAR
is the player's avatar identifier (usually a number, but other values can be used for custom avatars).
|gametype|GAMETYPE
|gen|GENNUM
|tier|TIERNAME
|rated
|rule|RULE: DESCRIPTION
Additional details when you join a battle room.
GAMETYPE
is one ofsingles
,doubles
, ortriples
;GENNUM
denotes the generation of Pokemon being played;tier
is the format; andrule
appears multiple times, once for each clause in effect.rated
only appears if the battle is rated.
|clearpoke
|poke|PLAYER|SPECIES
|poke|PLAYER|SPECIES
...
|teampreview
These messages appear if you're playing a format that uses team previews.
PLAYER
is the player ID (see|player|
) andSPECIES
is the species of the Pokemon.teampreview
commonly appears afterrule
tags instead of after the Pokemon in the team preview.
|request|REQUEST
Gives a JSON object containing a request for a decision (to move or switch). To assist in your decision,
REQUEST.active
has information about your active Pokemon, andREQUEST.side
has information about your your team as a whole.
|inactive|MESSAGE
or |inactiveoff|MESSAGE
A message related to the battle timer has been sent. The official client displays these messages in red.
inactive
means that the timer is on at the time the message was sent, whileinactiveoff
means that the timer is off.
|start
Indicates that the game has started.
|win|USER
USER
has won the battle.
|tie
The battle has ended in a tie.
Major actions
In battle, most Pokemon actions come in the form |ACTION|POKEMON|DETAILS
followed by a few messages detailing what happens after the action occurs.
A Pokemon is always identified in the form POSITION: NAME
. POSITION
is
the spot that the Pokemon is in: it consists of the PLAYER
of the player
(see |player|
), followed by a letter indicating the given Pokemon's
position, counting from a
.
In doubles and triples battles, a
will refer to the leftmost Pokemon
on one team and the rightmost Pokemon on the other (so p1a
faces p2c
,
etc). NAME
is the nickname of the Pokemon performing the action.
|move|POKEMON|MOVE|TARGET
The specified Pokemon has used move
MOVE
atTARGET
. If a move has multiple targets or no target,TARGET
should be ignored. If a move targets a side,TARGET
will be a (possibly fainted) pokemon on that side.
move
can be tagged with|[miss]
to indicate that the move missed.
|switch|POKEMON|SPECIES|HP STATUS
or |drag|POKEMON|SPECIES|HP STATUS
A Pokemon identified by
POKEMON
has switched in (the old Pokemon, if still there, is switched out).The new Pokemon has species
SPECIES
, HPHP
, and statusSTATUS
.HP
is specified as a fraction; if it is your own Pokemon then it will beCURRENT/MAX
, if not, it will be/100
if HP Percentage Mod is in effect and/48
otherwise.STATUS
can be left blank, or it can beslp
,par
, etc.
switch
means it was intentional, whiledrag
means it was unintentional (forced by Whirlwind, Roar, etc).
|detailschange|POKEMON|FORME|HP STATUS
or
|detailschange|POKEMON|FORME, GENDER|HP STATUS
or
|-formechange|POKEMON|FORME|HP STATUS
The specified Pokemon has changed formes (via Mega Evolution, ability, etc.) to
FORME
. If the forme change cannot be reverted (Mega Evolution or a Shaymin-Sky that is frozen), thendetailschange
will appear; otherwise, the client will send-formechange
.GENDER
can appear indetailschange
if the transforming Pokemon has a gender, displayed asM
orF
for male and female, respectively.
|cant|POKEMON|REASON
or |cant|POKEMON|REASON|MOVE
The Pokemon
POKEMON
could not perform a move because of the indicatedREASON
(such as paralysis, Disable, etc). Sometimes, the move it was trying to use is given.
|faint|POKEMON
The Pokemon
POKEMON
has fainted.
Minor actions
Minor actions are less important than major actions. In the official client, they're usually displayed in small font if they have a message. Pretty much anything that happens in a battle other than a switch or the fact that a move was used is a minor action. So yes, the effects of a move such as damage or stat boosts are minor actions.
Minor actions often come with tags such as |[from] EFFECT|[of] SOURCE
.
EFFECT
will be an effect (move, ability, item, status, etc), and SOURCE
will be a Pokemon. These can affect the message or animation displayed, but
do not affect anything else. Other tags include |[still]
(suppress
animation) and |[silent]
(suppress message).
|-fail|POKEMON|ACTION
The specified
ACTION
has failed against thePOKEMON
targetted. TheACTION
in question can be a move that fails, or a stat drop blocked by an ability like Hyper Cutter, in which caseACTION
will beunboost|STAT
, whereSTAT
indicates where the ability prevents stat drops. (For abilities that block all stat drops, like Clear Body,|STAT
does not appear.)
|-damage|POKEMON|HP STATUS
The specified Pokemon
POKEMON
has taken damage, and is now atHP STATUS
(see|switch|
for details).If
HP
is 0,STATUS
should be ignored. The current behavior is forSTATUS
to befnt
, but this may change and should not be relied upon.
|-heal|POKEMON|HP STATUS
Same as
-damage
, but the Pokemon has healed damage instead.
|-status|POKEMON|STATUS
The Pokemon
POKEMON
has been inflicted withSTATUS
.
|-curestatus|POKEMON|STATUS
The Pokemon
POKEMON
has recovered fromSTATUS
.
|-cureteam|POKEMON
The Pokemon
POKEMON
has used a move that cures its team of status effects, like Heal Bell.
|-boost|POKEMON|STAT|AMOUNT
The specified Pokemon
POKEMON
has gainedAMOUNT
inSTAT
, using the standard rules for Pokemon stat changes in-battle.STAT
is a standard three-letter abbreviation fot the stat in question, so Speed will bespe
, Special Defense will bespd
, etc.
|-unboost|POKEMON|STAT|AMOUNT
Same as
-boost
, but for negative stat changes instead.
|-weather|WEATHER
Indicates the weather that is currently in effect. If
|[upkeep]
is present, it means thatWEATHER
was active previously and is still in effect that turn. Otherwise, it means that the weather has changed due to a move or ability, or has expired, in which caseWEATHER
will benone
.
|-crit|POKEMON
A move has dealt a critical hit against the
POKEMON
.
|-supereffective|POKEMON
A move was super effective against the
POKEMON
.
|-resisted|POKEMON
A move was not very effective against the
POKEMON
.
|-immune|POKEMON
The
POKEMON
was immune to a move.
|-item|POKEMON|ITEM
The
ITEM
held by thePOKEMON
has been changed or revealed due to a move or ability. In addition, Air Balloon reveals itself when the Pokemon holding it switches in, so it will also cause this message to appear.
|-enditem|POKEMON|ITEM
The
ITEM
held byPOKEMON
has been destroyed, and it now holds no item. This can be because of an item's own effects (consumed Berries, Air Balloon), or by a move or ability, like Knock Off. If a berry is consumed, it also has an additional modifier|[eat]
to indicate that it was consumed. This message does not appear if the item's ownership was changed (with a move or ability like Thief or Trick), even if the move or ability would result in a Pokemon without an item.
|-ability|POKEMON|ABILITY
The
ABILITY
of thePOKEMON
has been changed or revealed due to a move or ability. This also includes abilities that reveal themselves upon switch-in, like Mold Breaker. The only move tha does not trigger this message is Skill Swap, so that if you use Skill Swap between teammates in a doubles or triples battle, the abilities of the two Pokemon are not revealed to the opponent, similar to its behavior in game.
|-endability|POKEMON
The
POKEMON
has had its ability surpressed, either by a move like Gastro Acid, or by the effects of Mummy.
|-transform|POKEMON|SPECIES
The Pokemon
POKEMON
has transformed intoSPECIES
by the effect of Transform or the ability Imposter.
|-activate|EFFECT
A miscellaneous effect has activated. This is triggered whenever an effect could not be better described by one of the other minor messages: for example, healing abilities like Water Absorb simply use
-heal
, and items that are consumed upon use have the-enditem
message instead.
|-hint|MESSAGE
Displays a message in parentheses to the client. Hint messages appear to explain and clarify why certain actions, such as Fake Out and Mat Block failing, have occurred,
when there would normally be no in-game messages.
|-message|MESSAGE
Displays a miscellaneous message to the client. These messages are primarily used for messages from game mods that aren't supported by the client, like rule clauses such as Sleep Clause, or other metagames with custom messages for specific scenarios. It is also used in triples battles for the automatic centering of Pokemon when only one remains on each side.
I'll document all the message types eventually, but for now this should be enough to get you started. You can watch the data sent and received from the server on a regular connection, or look at the client source code for a full list of message types.
####Global messages
|popup|MESSAGE
Show the user a popup containing
MESSAGE
.||
denotes a newline in the popup.
|pm|SENDER|RECEIVER|MESSAGE
A PM was sent from
SENDER
toRECEIVER
containing the messageMESSAGE
.
|usercount|USERCOUNT
USERCOUNT
is the number of users on the server.
|nametaken|USERNAME|MESSAGE
You tried to change your username to
USERNAME
but it failed for the reason described inMESSAGE
.
|challstr|KEYID|CHALLENGE
You just connected to the server, and we're giving you some information you'll need to log in.
If you're already logged in and have session cookies, you can make an HTTP GET request to
http://play.pokemonshowdown.com/action.php?act=upkeep&challengekeyid=KEYID&challenge=CHALLENGE
Otherwise, you'll need to make an HTTP POST request to
http://play.pokemonshowdown.com/action.php
with the dataact=login&name=USERNAME&pass=PASSWORD&challengekeyid=KEYID&challenge=CHALLENGE
USERNAME
is your username andPASSWORD
is your password, andKEYID
andCHALLENGE
are the values you got from|challstr|
. (Also feel free to make the request tohttps://
if your client supports it.)Either way, the response will start with
]
and be followed by a JSON object which we'll calldata
.Finish logging in (or renaming) by sending:
/trn USERNAME,0,ASSERTION
whereUSERNAME
is your desired username andASSERTION
isdata.assertion
.
|updateuser|USERNAME|NAMED|AVATAR
Your name or avatar was successfully changed. Your username is now
USERNAME
.NAMED
will be0
if you are a guest or1
otherwise. And your avatar is nowAVATAR
.
|formats|FORMATSLIST
This server supports the formats specified in
FORMATSLIST
.FORMATSLIST
is a|
-separated list ofFORMAT
s.FORMAT
is a format name with one or more of these suffixes:,#
if the format uses random teams,,,
if the format is only available for searching, and,
if the format is only available for challenging. Sections are separated by two vertical bars with the number of the column of that section prefixed by,
in it. After that follows the name of the section and another vertical bar.
|updatesearch|JSON
JSON
is a JSON object representing the current state of what battles the user is currently searching for.
|updatechallenges|JSON
JSON
is a JSON object representing the current state of who the user is challenging and who is challenging the user.
|queryresponse|QUERYTYPE|JSON
JSON
is a JSON object representing containing the data that was requested with/query QUERYTYPE
or/query QUERYTYPE DETAILS
.Possible queries include
/query roomlist
and/query userdetails USERNAME
.