Pokémon Showdown’s protocol is relatively simple.
Pokémon Showdown is implemented in SockJS. SockJS is a compatibility layer over raw WebSocket, so you can actually connect to Pokémon Showdown directly using WebSocket:
ws://sim.smogon.com:8000/showdown/websocket
or
wss://sim3.psim.us/showdown/websocket
Client implementations you might want to look at for reference include:
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 unneeded (commands like /join lobby
can be sent anywhere). Responses will be sent to a PM box with no username
(so |/command is equivalent to |/pm &, /command).
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.
|init|ROOMTYPE
The first message received from a room when you join it.
ROOMTYPEis one of:chatorbattle
|title|TITLE
TITLEis the title of the room. The title is not guaranteed to resemble the room ID; for instance, roombattle-gen7uu-779767714could have titleAlice vs. Bob.
|users|USERLIST
USERLISTis a comma-separated list ofUSERs, sent from chat rooms when they’re joined. Optionally, aUSERcan end in@followed by a user status message. ASTATUSstarting in!indicates the user is away.
||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.
|uhtml|NAME|HTML
We recieved an HTML message (NAME) that can change what it’s displaying, this is used in things like our Polls system, for example.
|uhtmlchange|NAME|HTML
Changes the HTML display of the
|uhtml|message named (NAME).
|join|USER, |j|USER, or |J|USER
USERjoined the room. Optionally,USERmay be appended with@!to indicate that the user is away or busy.
|leave|USER, |l|USER, or |L|USER
USERleft the room.
|name|USER|OLDID, |n|USER|OLDID, or |N|USER|OLDID
A user changed name to
USER, and their previous userid wasOLDID. Optionally,USERmay be appended with@!to indicate that the user is away or busy.
|chat|USER|MESSAGE or |c|USER|MESSAGE
USERsaidMESSAGE. Note thatMESSAGEcan contain|characters, so you can’t just split by|and take the fourth string.If
MESSAGEstarts with/, it is a special message. For instance,/me TEXTor/announce TEXTor/uhtml HTML. A lot of these message types are abused to embed protocol messages in PMs (for instance,/uhtmlis a stopgap before the client is rewritten to support|uhtml|etc in PMs).If the server wants clients to actually render a message starting with
/, it will send a message starting with//(exactly like how users need to send those messages).
|notify|TITLE|MESSAGE
Send a notification with
TITLEandMESSAGE(usually,TITLEwill be bold, andMESSAGEis optional).
|notify|TITLE|MESSAGE|HIGHLIGHTTOKEN
Send a notification as above, but only if the user would be notified by a chat message containing
HIGHLIGHTTOKEN(i.e. ifHIGHLIGHTTOKENcontains words added to/highlight, or their username by default.)
|:|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
USER1andUSER2, and the battle room has IDROOMID.
|popup|MESSAGE
Show the user a popup containing
MESSAGE.||denotes a newline in the popup.
|pm|SENDER|RECEIVER|MESSAGE
A PM was sent from
SENDERtoRECEIVERcontaining the messageMESSAGE.
|usercount|USERCOUNT
USERCOUNTis the number of users on the server.
|nametaken|USERNAME|MESSAGE
You tried to change your username to
USERNAMEbut it failed for the reason described inMESSAGE.
|challstr|CHALLSTR
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
https://play.pokemonshowdown.com/api/upkeep?challstr=CHALLSTROtherwise, you’ll need to make an HTTP POST request to
https://play.pokemonshowdown.com/api/loginwith the dataname=USERNAME&pass=PASSWORD&challstr=CHALLSTR
USERNAMEis your username andPASSWORDis your password, andCHALLSTRis the value you got from|challstr|. Note thatCHALLSTRcontains|characters. (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,ASSERTIONwhereUSERNAMEis your desired username andASSERTIONisdata.assertion.
|updateuser|USER|NAMED|AVATAR|SETTINGS
Your name, avatar or settings were successfully changed. Your rank and username are now
USER. Optionally,USERmay be appended with@!to indicate that you are away or busy.NAMEDwill be0if you are a guest or1otherwise. Your avatar is nowAVATAR.SETTINGSis a JSON object representing the current state of various user settings.
|formats|FORMATSLIST
This server supports the formats specified in
FORMATSLIST.FORMATSLISTis a|-separated list ofFORMATs.FORMATis 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
JSONis a JSON object representing the current state of what battles the user is currently searching for.
|updatechallenges|JSON
JSONis a JSON object representing the current state of who the user is challenging and who is challenging the user.
|queryresponse|QUERYTYPE|JSON
JSONis a JSON object representing containing the data that was requested with/query QUERYTYPEor/query QUERYTYPE DETAILS.Possible queries include
/query roomlistand/query userdetails USERNAME.
|tournament|create|FORMAT|GENERATOR|PLAYERCAP
FORMATis the name of the format in which each battle will be played.GENERATORis eitherEliminationorRound Robinand describes the type of bracket that will be used.Eliminationincludes a prefix that denotes the number of times a player can lose before being eliminated (Single,Double, etc.).Round Robinincludes the prefixDoubleif every matchup will battle twice.PLAYERCAPis a number representing the maximum amount of players that can join the tournament or0if no cap was specified.
|tournament|update|JSON
JSONis a JSON object representing the changes in the tournament since the last update you recieved or the start of the tournament. These include:format: the tournament's custom name or the format being used teambuilderFormat: the format being used; sent if a custom name was set isStarted: whether or not the tournament has started isJoined: whether or not you have joined the tournament generator: the type of bracket being used by the tournament playerCap: the player cap that was set or 0 if it was removed bracketData: an object representing the current state of the bracket challenges: a list of opponents that you can currently challenge challengeBys: a list of opponents that can currently challenge you challenged: the name of the opponent that has challenged you challenging: the name of the opponent that you are challenging
|tournament|updateEnd
Signals the end of an update period.
|tournament|error|ERROR
An error of type
ERRORoccurred.
|tournament|forceend
The tournament was forcibly ended.
|tournament|join|USER
USERjoined the tournament.
|tournament|leave|USER
USERleft the tournament.
|tournament|replace|OLD|NEW
The player
OLDhas been replaced withNEW
|tournament|start|NUMPLAYERS
The tournament started with
NUMPLAYERSparticipants.
|tournament|replace|USER1|USER2
USER1was replaced byUSER2.
|tournament|disqualify|USER
USERwas disqualified from the tournament.
|tournament|battlestart|USER1|USER2|ROOMID
A tournament battle started between
USER1andUSER2, and the battle room has IDROOMID.
|tournament|battleend|USER1|USER2|RESULT|SCORE|RECORDED|ROOMID
The tournament battle between
USER1andUSER2in the battle roomROOMIDended.RESULTdescribes the outcome of the battle fromUSER1’s perspective (win,loss, ordraw).SCOREis an array of length 2 that denotes the number of PokemonUSER1had left and the number of PokemonUSER2had left.RECORDEDwill befailif the battle ended in a draw and the bracket type does not support draws. Otherwise, it will besuccess.
|tournament|end|JSON
The tournament ended.
JSONis a JSON object containing:results: the name(s) of the winner(s) of the tournament format: the tournament's custom name or the format that was used generator: the type of bracket that was used by the tournament bracketData: an object representing the final state of the bracket
|tournament|scouting|SETTING
Players are now either allowed or not allowed to join other tournament battles based on
SETTING(allowordisallow).
|tournament|autostart|on|TIMEOUT
A timer was set for the tournament to auto-start in
TIMEOUTseconds.
|tournament|autostart|off
The timer for the tournament to auto-start was turned off.
|tournament|autodq|on|TIMEOUT
A timer was set for the tournament to auto-disqualify inactive players every
TIMEOUTseconds.
|tournament|autodq|off
The timer for the tournament to auto-disqualify inactive players was turned off.
|tournament|autodq|target|TIME
You have
TIMEseconds to make or accept a challenge, or else you will be disqualified for inactivity.
Battle rooms will have a mix of room messages and battle messages. Battle
messages are documented in SIM-PROTOCOL.md.
To make decisions in battle, players should use the /choose command,
also documented in SIM-PROTOCOL.md.
|updatechallenges|JSON
JSONis a JSON object representing the current state of who the user is challenging and who is challenging the user. You’ll get this whenever challenges update (when you challenge someone, when you receive a challenge, when you or someone you challenged accepts/rejects/cancels a challenge).
JSON.challengesFrom will be a {userid: format} table of received
challenges.
JSON.challengeTo will be a challenge if you’re challenging someone, or null
if you haven’t.
If you are challenging someone, challengeTo will be in the format:
{"to":"player1","format":"gen7randombattle"}.
To challenge someone, send:
/utm TEAM
/challenge USERNAME, FORMAT
To cancel a challenge you made to someone, send:
/cancelchallenge USERNAME
To reject a challenge you received from someone, send:
/reject USERNAME
To accept a challenge you received from someone, send:
/utm TEAM
/accept USERNAME
Teams are in packed format. TEAM can also be
null, if the format doesn’t require user-built teams, such as Random Battle.
Invalid teams will send a |popup| with validation errors, and the /accept
or /challenge command won’t take effect.
If the challenge is accepted, you will receive a room initialization message.
|updatesearch|JSON
JSONis a JSON object representing the current state of what battles the user is currently searching for. You’ll get this whenever searches update (when you search, cancel a search, or you start or end a battle)
JSON.searching will be an array of format IDs you’re currently searching for
games in.
JSON.games will be a {roomid: title} table of games you’re currently in.
Note that this includes ALL games, so |updatesearch| will be sent when you
start/end challenge battles, and even non-Pokémon games like Mafia.
To search for a battle against a random opponent, send:
/utm TEAM
/search FORMAT
Teams are in packed format (see “Team format” below). TEAM can also be
null, if the format doesn’t require user-built teams, such as Random Battle.
To cancel searching, send:
/cancelsearch
Pokémon Showdown always sends teams over the protocol in packed format. For details about how to convert and read this format, see sim/TEAMS.md.
If you’re not using JavaScript and don’t want to reimplement these conversions, Pokémon Showdown’s command-line client can convert between packed teams and JSON using standard IO.