transmission/docs/rpc-spec.md

Transmission's RPC specification

This document describes a protocol for interacting with Transmission sessions remotely.

1.1 Terminology

The JSON terminology in RFC 4627 is used. RPC requests and responses are formatted in JSON.

1.2 Tools

If transmission-remote is called with a --debug argument, its RPC traffic to the Transmission server will be dumped to the terminal. This can be useful when you want to compare requests in your application to another for reference.

If transmission-qt is run with an environment variable TR_RPC_VERBOSE set, it too will dump the RPC requests and responses to the terminal for inspection.

Lastly, using the browser's developer tools in the Transmission web client is always an option.

1.3 Libraries of ready-made wrappers

Some people outside of the Transmission project have written libraries that wrap this RPC API. These aren't supported by the Transmission project, but are listed here in the hope that they may be useful:

Language	Link
C#	https://www.nuget.org/packages/Transmission.API.RPC
Go	https://github.com/hekmon/transmissionrpc
Python	https://github.com/Trim21/transmission-rpc
Rust	https://crates.io/crates/transmission-rpc

2 Message format

Messages are formatted as objects. There are two types: requests (described in section 2.1) and responses (described in section 2.2).

All text must be UTF-8 encoded.

2.1 Requests

Requests support three keys:

1. A required method string telling the name of the method to invoke
2. An optional arguments object of key/value pairs. The keys allowed are defined by the method.
3. An optional tag number used by clients to track responses. If provided by a request, the response MUST include the same tag.

{
   "arguments": {
     "fields": [
       "version"
     ]
   },
   "method": "session-get",
   "tag": 912313
}

2.2 Responses

Responses to a request will include:

1. A required result string whose value MUST be success on success, or an error string on failure.
2. An optional arguments object of key/value pairs. Its keys contents are defined by the method and arguments of the original request.
3. An optional tag number as described in 2.1.

{
   "arguments": {
      "version": "2.93 (3c5870d4f5)"
   },
   "result": "success",
   "tag": 912313
}

2.3 Transport mechanism

HTTP POSTing a JSON-encoded request is the preferred way of communicating with a Transmission RPC server. The current Transmission implementation has the default URL as http://host:9091/transmission/rpc. Clients may use this as a default, but should allow the URL to be reconfigured, since the port and path may be changed to allow mapping and/or multiple daemons to run on a single server.

2.3.1 CSRF protection

Most Transmission RPC servers require a X-Transmission-Session-Id header to be sent with requests, to prevent CSRF attacks.

When your request has the wrong id -- such as when you send your first request, or when the server expires the CSRF token -- the Transmission RPC server will return an HTTP 409 error with the right X-Transmission-Session-Id in its own headers.

So, the correct way to handle a 409 response is to update your X-Transmission-Session-Id and to resend the previous request.

2.3.2 DNS rebinding protection

Additional check is being made on each RPC request to make sure that the client sending the request does so using one of the allowed hostnames by which RPC server is meant to be available.

If host whitelisting is enabled (which is true by default), Transmission inspects the Host: HTTP header value (with port stripped, if any) and matches it to one of the whitelisted names. Regardless of host whitelist content, localhost and localhost. domain names as well as all the IP addresses are always implicitly allowed.

For more information on configuration, see settings.json documentation for rpc-host-whitelist-enabled and rpc-host-whitelist keys.

2.3.3 Authentication

Enabling authentication is an optional security feature that can be enabled on Transmission RPC servers. Authentication occurs by method of HTTP Basic Access Authentication.

If authentication is enabled, Transmission inspects the Authorization: HTTP header value to validate the credentials of the request. The value of this HTTP header is expected to be Basic <b64 credentials>, where is equal to a base64 encoded string of the username and password (respectively), separated by a colon.

3 Torrent requests

3.1 Torrent action requests

Method name	libtransmission function
torrent-start	tr_torrentStart
torrent-start-now	tr_torrentStartNow
torrent-stop	tr_torrentStop
torrent-verify	tr_torrentVerify
torrent-reannounce	tr_torrentManualUpdate ("ask tracker for more peers")

Request arguments: ids, which specifies which torrents to use. All torrents are used if the ids argument is omitted.

ids should be one of the following:

1. an integer referring to a torrent id
2. a list of torrent id numbers, SHA1 hash strings, or both
3. a string, recently-active, for recently-active torrents

Response arguments: none

3.2 Torrent mutator: torrent-set

Method name: torrent-set

Request arguments:

Key	Value Type	Value Description
bandwidthPriority	number	this torrent's bandwidth tr_priority_t
downloadLimit	number	maximum download speed (KBps)
downloadLimited	boolean	true if downloadLimit is honored
files-unwanted	array	indices of file(s) to not download
files-wanted	array	indices of file(s) to download
group	string	The name of this torrent's bandwidth group
honorsSessionLimits	boolean	true if session upload limits are honored
ids	array	torrent list, as described in 3.1
labels	array	array of string labels
location	string	new location of the torrent's content
peer-limit	number	maximum number of peers
priority-high	array	indices of high-priority file(s)
priority-low	array	indices of low-priority file(s)
priority-normal	array	indices of normal-priority file(s)
queuePosition	number	position of this torrent in its queue [0...n)
seedIdleLimit	number	torrent-level number of minutes of seeding inactivity
seedIdleMode	number	which seeding inactivity to use. See tr_idlelimit
seedRatioLimit	double	torrent-level seeding ratio
seedRatioMode	number	which ratio to use. See tr_ratiolimit
trackerAdd	array	DEPRECATED use trackerList instead
trackerList	string	string of announce URLs, one per line, and a blank line between tiers.
trackerRemove	array	DEPRECATED use trackerList instead
trackerReplace	array	DEPRECATED use trackerList instead
uploadLimit	number	maximum upload speed (KBps)
uploadLimited	boolean	true if uploadLimit is honored

Just as an empty ids value is shorthand for "all ids", using an empty array for files-wanted, files-unwanted, priority-high, priority-low, or priority-normal is shorthand for saying "all files".

Response arguments: none

3.3 Torrent accessor: torrent-get

Method name: torrent-get.

Request arguments:

1. An optional ids array as described in 3.1.
2. A required fields array of keys. (see list below)
3. An optional format string specifying how to format the torrents response field. Allowed values are objects (default) and table. (see "Response arguments" below)

Response arguments:

1. A torrents array.

   If the format request was objects (default), torrents will be an array of objects, each of which contains the key/value pairs matching the request's fields arg. This was the only format before Transmission 3 and has some obvious programmer conveniences, such as parsing directly into Javascript objects.

   If the format was table, then torrents will be an array of arrays. The first row holds the keys and each remaining row holds a torrent's values for those keys. This format is more efficient in terms of JSON generation and JSON parsing.

2. If the request's ids field was recently-active, a removed array of torrent-id numbers of recently-removed torrents.

Note: For more information on what these fields mean, see the comments in libtransmission/transmission.h. The 'source' column here corresponds to the data structure there.

Key	Value Type	transmission.h source
activityDate	number	tr_stat
addedDate	number	tr_stat
availability	array (see below)	tr_torrentAvailability()
bandwidthPriority	number	tr_priority_t
comment	string	tr_torrent_view
corruptEver	number	tr_stat
creator	string	tr_torrent_view
dateCreated	number	tr_torrent_view
desiredAvailable	number	tr_stat
doneDate	number	tr_stat
downloadDir	string	tr_torrent
downloadedEver	number	tr_stat
downloadLimit	number	tr_torrent
downloadLimited	boolean	tr_torrent
editDate	number	tr_stat
error	number	tr_stat
errorString	string	tr_stat
eta	number	tr_stat
etaIdle	number	tr_stat
file-count	number	tr_info
files	array (see below)	n/a
fileStats	array (see below)	n/a
group	string	n/a
hashString	string	tr_torrent_view
haveUnchecked	number	tr_stat
haveValid	number	tr_stat
honorsSessionLimits	boolean	tr_torrent
id	number	tr_torrent
isFinished	boolean	tr_stat
isPrivate	boolean	tr_torrent
isStalled	boolean	tr_stat
labels	array of strings	tr_torrent
leftUntilDone	number	tr_stat
magnetLink	string	n/a
manualAnnounceTime	number	tr_stat
maxConnectedPeers	number	tr_torrent
metadataPercentComplete	double	tr_stat
name	string	tr_torrent_view
peer-limit	number	tr_torrent
peers	array (see below)	n/a
peersConnected	number	tr_stat
peersFrom	object (see below)	n/a
peersGettingFromUs	number	tr_stat
peersSendingToUs	number	tr_stat
percentComplete	double	tr_stat
percentDone	double	tr_stat
pieces	string (see below)	tr_torrent
pieceCount	number	tr_torrent_view
pieceSize	number	tr_torrent_view
priorities	array (see below)	n/a
primary-mime-type	string	tr_torrent
queuePosition	number	tr_stat
rateDownload (B/s)	number	tr_stat
rateUpload (B/s)	number	tr_stat
recheckProgress	double	tr_stat
secondsDownloading	number	tr_stat
secondsSeeding	number	tr_stat
seedIdleLimit	number	tr_torrent
seedIdleMode	number	tr_inactivelimit
seedRatioLimit	double	tr_torrent
seedRatioMode	number	tr_ratiolimit
sizeWhenDone	number	tr_stat
startDate	number	tr_stat
status	number (see below)	tr_stat
trackers	array (see below)	n/a
trackerList	string	string of announce URLs, one per line, with a blank line between tiers
trackerStats	array (see below)	n/a
totalSize	number	tr_torrent_view
torrentFile	string	tr_info
uploadedEver	number	tr_stat
uploadLimit	number	tr_torrent
uploadLimited	boolean	tr_torrent
uploadRatio	double	tr_stat
wanted	array (see below)	n/a
webseeds	array of strings	tr_tracker_view
webseedsSendingToUs	number	tr_stat

availability: An array of pieceCount numbers representing the number of connected peers that have each piece, or -1 if we already have the piece ourselves.

files: array of objects, each containing:

Key	Value Type	transmission.h source
bytesCompleted	number	tr_file_view
length	number	tr_file_view
name	string	tr_file_view

fileStats: a file's non-constant properties. An array of tr_info.filecount objects, each containing:

Key	Value Type	transmission.h source
bytesCompleted	number	tr_file_view
wanted	number	tr_file_view (Note: For backwards compatibility, this is serialized as an array of 0 or 1 that should be treated as booleans)
priority	number	tr_file_view

peers: an array of objects, each containing:

Key	Value Type	transmission.h source
address	string	tr_peer_stat
clientName	string	tr_peer_stat
clientIsChoked	boolean	tr_peer_stat
clientIsInterested	boolean	tr_peer_stat
flagStr	string	tr_peer_stat
isDownloadingFrom	boolean	tr_peer_stat
isEncrypted	boolean	tr_peer_stat
isIncoming	boolean	tr_peer_stat
isUploadingTo	boolean	tr_peer_stat
isUTP	boolean	tr_peer_stat
peerIsChoked	boolean	tr_peer_stat
peerIsInterested	boolean	tr_peer_stat
port	number	tr_peer_stat
progress	double	tr_peer_stat
rateToClient (B/s)	number	tr_peer_stat
rateToPeer (B/s)	number	tr_peer_stat

peersFrom: an object containing:

Key	Value Type	transmission.h source
fromCache	number	tr_stat
fromDht	number	tr_stat
fromIncoming	number	tr_stat
fromLpd	number	tr_stat
fromLtep	number	tr_stat
fromPex	number	tr_stat
fromTracker	number	tr_stat

pieces: A bitfield holding pieceCount flags which are set to 'true' if we have the piece matching that position. JSON doesn't allow raw binary data, so this is a base64-encoded string. (Source: tr_torrent)

priorities: An array of tr_torrentFileCount() numbers. Each is the tr_priority_t mode for the corresponding file.

status: A number between 0 and 6, where:

Value	Meaning
0	Torrent is stopped
1	Torrent is queued to verify local data
2	Torrent is verifying local data
3	Torrent is queued to download
4	Torrent is downloading
5	Torrent is queued to seed
6	Torrent is seeding

trackers: array of objects, each containing:

Key	Value Type	transmission.h source
announce	string	tr_tracker_view
id	number	tr_tracker_view
scrape	string	tr_tracker_view
sitename	string	tr_tracker_view
tier	number	tr_tracker_view

trackerStats: array of objects, each containing:

Key	Value Type	transmission.h source
announceState	number	tr_tracker_view
announce	string	tr_tracker_view
downloadCount	number	tr_tracker_view
hasAnnounced	boolean	tr_tracker_view
hasScraped	boolean	tr_tracker_view
host	string	tr_tracker_view
id	number	tr_tracker_view
isBackup	boolean	tr_tracker_view
lastAnnouncePeerCount	number	tr_tracker_view
lastAnnounceResult	string	tr_tracker_view
lastAnnounceStartTime	number	tr_tracker_view
lastAnnounceSucceeded	boolean	tr_tracker_view
lastAnnounceTime	number	tr_tracker_view
lastAnnounceTimedOut	boolean	tr_tracker_view
lastScrapeResult	string	tr_tracker_view
lastScrapeStartTime	number	tr_tracker_view
lastScrapeSucceeded	boolean	tr_tracker_view
lastScrapeTime	number	tr_tracker_view
lastScrapeTimedOut	boolean	tr_tracker_view
leecherCount	number	tr_tracker_view
nextAnnounceTime	number	tr_tracker_view
nextScrapeTime	number	tr_tracker_view
scrapeState	number	tr_tracker_view
scrape	string	tr_tracker_view
seederCount	number	tr_tracker_view
sitename	string	tr_tracker_view
tier	number	tr_tracker_view

wanted: An array of tr_torrentFileCount() Booleans true if the corresponding file is to be downloaded. (Source: tr_file_view)

Example:

Say we want to get the name and total size of torrents #7 and #10.

Request:

{
   "arguments": {
       "fields": [ "id", "name", "totalSize" ],
       "ids": [ 7, 10 ]
   },
   "method": "torrent-get",
   "tag": 39693
}

Response:

{
   "arguments": {
      "torrents": [
         {
             "id": 10,
             "name": "Fedora x86_64 DVD",
             "totalSize": 34983493932
         },
         {
             "id": 7,
             "name": "Ubuntu x86_64 DVD",
             "totalSize": 9923890123
         }
      ]
   },
   "result": "success",
   "tag": 39693
}

3.4 Adding a torrent

Method name: torrent-add

Request arguments:

Key	Value Type	Description
cookies	string	pointer to a string of one or more cookies.
download-dir	string	path to download the torrent to
filename	string	filename or URL of the .torrent file
labels	array	array of string labels
metainfo	string	base64-encoded .torrent content
paused	boolean	if true, don't start the torrent
peer-limit	number	maximum number of peers
bandwidthPriority	number	torrent's bandwidth tr_priority_t
files-wanted	array	indices of file(s) to download
files-unwanted	array	indices of file(s) to not download
priority-high	array	indices of high-priority file(s)
priority-low	array	indices of low-priority file(s)
priority-normal	array	indices of normal-priority file(s)

Either filename or metainfo must be included. All other arguments are optional.

The format of the cookies should be NAME=CONTENTS, where NAME is the cookie name and CONTENTS is what the cookie should contain. Set multiple cookies like this: name1=content1; name2=content2; etc. See libcurl documentation for more information.

Response arguments:

• On success, a torrent-added object in the form of one of 3.3's torrent objects with the fields for id, name, and hashString.

• When attempting to add a duplicate torrent, a torrent-duplicate object in the same form is returned, but the response's result value is still success.

3.5 Removing a torrent

Method name: torrent-remove

Key	Value Type	Description
ids	array	torrent list, as described in 3.1
delete-local-data	boolean	delete local data. (default: false)

Response arguments: none

3.6 Moving a torrent

Method name: torrent-set-location

Request arguments:

Key	Value Type	Description
ids	array	torrent list, as described in 3.1
location	string	the new torrent location
move	boolean	if true, move from previous location. otherwise, search "location" for files (default: false)

Response arguments: none

3.7 Renaming a torrent's path

Method name: torrent-rename-path

For more information on the use of this function, see the transmission.h documentation of tr_torrentRenamePath(). In particular, note that if this call succeeds you'll want to update the torrent's files and name field with torrent-get.

Request arguments:

Key	Value Type	Description
ids	array	the torrent list, as described in 3.1 (must only be 1 torrent)
path	string	the path to the file or folder that will be renamed
name	string	the file or folder's new name

Response arguments: path, name, and id, holding the torrent ID integer

4 Session requests

4.1 Session arguments

Key	Value Type	Description
alt-speed-down	number	max global download speed (KBps)
alt-speed-enabled	boolean	true means use the alt speeds
alt-speed-time-begin	number	when to turn on alt speeds (units: minutes after midnight)
alt-speed-time-day	number	what day(s) to turn on alt speeds (look at tr_sched_day)
alt-speed-time-enabled	boolean	true means the scheduled on/off times are used
alt-speed-time-end	number	when to turn off alt speeds (units: same)
alt-speed-up	number	max global upload speed (KBps)
blocklist-enabled	boolean	true means enabled
blocklist-size	number	number of rules in the blocklist
blocklist-url	string	location of the blocklist to use for blocklist-update
cache-size-mb	number	maximum size of the disk cache (MB)
config-dir	string	location of transmission's configuration directory
default-trackers	string	announce URLs, one per line, and a blank line between tiers.
dht-enabled	boolean	true means allow DHT in public torrents
download-dir	string	default path to download torrents
download-dir-free-space	number	DEPRECATED Use the free-space method instead.
download-queue-enabled	boolean	if true, limit how many torrents can be downloaded at once
download-queue-size	number	max number of torrents to download at once (see download-queue-enabled)
encryption	string	required, preferred, tolerated
idle-seeding-limit-enabled	boolean	true if the seeding inactivity limit is honored by default
idle-seeding-limit	number	torrents we're seeding will be stopped if they're idle for this long
incomplete-dir-enabled	boolean	true means keep torrents in incomplete-dir until done
incomplete-dir	string	path for incomplete torrents, when enabled
lpd-enabled	boolean	true means allow Local Peer Discovery in public torrents
peer-limit-global	number	maximum global number of peers
peer-limit-per-torrent	number	maximum global number of peers
peer-port-random-on-start	boolean	true means pick a random peer port on launch
peer-port	number	port number
pex-enabled	boolean	true means allow PEX in public torrents
port-forwarding-enabled	boolean	true means ask upstream router to forward the configured peer port to transmission using UPnP or NAT-PMP
queue-stalled-enabled	boolean	whether or not to consider idle torrents as stalled
queue-stalled-minutes	number	torrents that are idle for N minuets aren't counted toward seed-queue-size or download-queue-size
rename-partial-files	boolean	true means append .part to incomplete files
rpc-version-minimum	number	the minimum RPC API version supported
rpc-version-semver	string	the current RPC API version in a semver-compatible string
rpc-version	number	the current RPC API version
script-torrent-added-enabled	boolean	whether or not to call the added script
script-torrent-added-filename	string	filename of the script to run
script-torrent-done-enabled	boolean	whether or not to call the done script
script-torrent-done-filename	string	filename of the script to run
script-torrent-done-seeding-enabled	boolean	whether or not to call the seeding-done script
script-torrent-done-seeding-filename	string	filename of the script to run
seed-queue-enabled	boolean	if true, limit how many torrents can be uploaded at once
seed-queue-size	number	max number of torrents to uploaded at once (see seed-queue-enabled)
seedRatioLimit	double	the default seed ratio for torrents to use
seedRatioLimited	boolean	true if seedRatioLimit is honored by default
speed-limit-down-enabled	boolean	true means enabled
speed-limit-down	number	max global download speed (KBps)
speed-limit-up-enabled	boolean	true means enabled
speed-limit-up	number	max global upload speed (KBps)
start-added-torrents	boolean	true means added torrents will be started right away
trash-original-torrent-files	boolean	true means the .torrent file of added torrents will be deleted
units	object	see below
utp-enabled	boolean	true means allow UTP
version	string	long version string $version ($revision)

units: an object containing:

Key	Value Type	transmission.h source
speed-units	array	4 strings: KB/s, MB/s, GB/s, TB/s
speed-bytes	number	number of bytes in a KB (1000 for kB; 1024 for KiB)
size-units	array	4 strings: KB/s, MB/s, GB/s, TB/s
size-bytes	number	number of bytes in a KB (1000 for kB; 1024 for KiB)
memory-units	array	4 strings: KB/s, MB/s, GB/s, TB/s
memory-bytes	number	number of bytes in a KB (1000 for kB; 1024 for KiB)

rpc-version indicates the RPC interface version supported by the RPC server. It is incremented when a new version of Transmission changes the RPC interface.

rpc-version-minimum indicates the oldest API supported by the RPC server. It is changes when a new version of Transmission changes the RPC interface in a way that is not backwards compatible. There are no plans for this to be common behavior.

4.1.1 Mutators

Method name: session-set

Request arguments: the mutable properties from 4.1's arguments, i.e. all of them except:

• blocklist-size
• config-dir
• rpc-version-minimum,
• rpc-version-semver
• rpc-version
• session-id
• version

Response arguments: none

4.1.2 Accessors

Method name: session-get

Request arguments: an optional fields array of keys (see 4.1)

Response arguments: key/value pairs matching the request's fields argument if present, or all supported fields (see 4.1) otherwise.

4.2 Session statistics

Method name: session-stats

Request arguments: none

Response arguments:

Key	Value Type	Description
activeTorrentCount	number
downloadSpeed	number
pausedTorrentCount	number
torrentCount	number
uploadSpeed	number
cumulative-stats	stats object (see below)
current-stats	stats object (see below)

A stats object contains:

Key	Value Type	transmission.h source
uploadedBytes	number	tr_session_stats
downloadedBytes	number	tr_session_stats
filesAdded	number	tr_session_stats
sessionCount	number	tr_session_stats
secondsActive	number	tr_session_stats

4.3 Blocklist

Method name: blocklist-update

Request arguments: none

Response arguments: a number blocklist-size

4.4 Port checking

This method tests to see if your incoming peer port is accessible from the outside world.

Method name: port-test

Request arguments: none

Response arguments: a Boolean, port-is-open

4.5 Session shutdown

This method tells the transmission session to shut down.

Method name: session-close

Request arguments: none

Response arguments: none

4.6 Queue movement requests

Method name	transmission.h source
queue-move-top	tr_torrentQueueMoveTop()
queue-move-up	tr_torrentQueueMoveUp()
queue-move-down	tr_torrentQueueMoveDown()
queue-move-bottom	tr_torrentQueueMoveBottom()

Request arguments:

Key	Value Type	Description
ids	array	torrent list, as described in 3.1.

Response arguments: none

4.7 Free space

This method tests how much free space is available in a client-specified folder.

Method name: free-space

Request arguments:

Key	Value type	Description
path	string	the directory to query

Response arguments:

Key	Value type	Description
path	string	same as the Request argument
size-bytes	number	the size, in bytes, of the free space in that directory
total_size	number	the total capacity, in bytes, of that directory

4.8 Bandwidth groups

4.8.1 Bandwidth group mutator: group-set

Method name: group-set

Request parameters:

Key	Value type	Description
honorsSessionLimits	boolean	true if session upload limits are honored
name	string	Bandwidth group name
speed-limit-down-enabled	boolean	true means enabled
speed-limit-down	number	max global download speed (KBps)
speed-limit-up-enabled	boolean	true means enabled
speed-limit-up	number	max global upload speed (KBps)

Response arguments: none

4.8.2 Bandwidth group accessor: group-get

Method name: group-get

Request arguments: An optional argument group. group is either a string naming the bandwidth group, or a list of such strings. If group is omitted, all bandwidth groups are used.

Response arguments:

Key	Value type	Description
group	array	A list of bandwidth group description objects

A bandwidth group description object has:

Key	Value type	Description
honorsSessionLimits	boolean	true if session upload limits are honored
name	string	Bandwidth group name
speed-limit-down-enabled	boolean	true means enabled
speed-limit-down	number	max global download speed (KBps)
speed-limit-up-enabled	boolean	true means enabled
speed-limit-up	number	max global upload speed (KBps)

5 Protocol versions

This section lists the changes that have been made to the RPC protocol.

There are two ways to check for API compatibility. Since most developers know semver, session-get's rpc-version-semver is the recommended way. That value is a semver-compatible string of the RPC protocol version number.

Since Transmission predates the semver 1.0 spec, the previous scheme was for the RPC version to be a whole number and to increment it whenever a change was made. That is session-get's rpc-version. rpc-version-minimum lists the oldest version that is compatible with the current version; i.e. an app coded to use rpc-version-minimum would still work on a Transmission release running rpc-version.

Breaking changes are denoted with a 💣 emoji.

Transmission 1.30 (rpc-version-semver 1.0.0, rpc-version: 1)

Initial revision.

Transmission 1.40 (rpc-version-semver 1.1.0, rpc-version: 2)

Method	Description
torrent-get	new port to peers

Transmission 1.41 (rpc-version-semver 1.2.0, rpc-version: 3)

Method	Description
session-get	new arg version
torrent-get	new arg downloaders
torrent-remove	new method

Transmission 1.50 (rpc-version-semver 1.3.0, rpc-version: 4)

Method	Description
session-get	new arg rpc-version-minimum
session-get	new arg rpc-version
session-stats	added cumulative-stats
session-stats	added current-stats
torrent-get	new arg downloadDir

Transmission 1.60 (rpc-version-semver 2.0.0, rpc-version: 5)

Method	Description
session-get	💣 renamed peer-limit to peer-limit-global
session-get	💣 renamed pex-allowed to pex-enabled
session-get	💣 renamed port to peer-port
torrent-get	💣 removed arg downloadLimitMode
torrent-get	💣 removed arg uploadLimitMode
torrent-set	💣 renamed speed-limit-down-enabled to downloadLimited
torrent-set	💣 renamed speed-limit-down to downloadLimit
torrent-set	💣 renamed speed-limit-up-enabled to uploadLimited
torrent-set	💣 renamed speed-limit-up to uploadLimit
blocklist-update	new method
port-test	new method
session-get	new arg alt-speed-begin
session-get	new arg alt-speed-down
session-get	new arg alt-speed-enabled
session-get	new arg alt-speed-end
session-get	new arg alt-speed-time-enabled
session-get	new arg alt-speed-up
session-get	new arg blocklist-enabled
session-get	new arg blocklist-size
session-get	new arg peer-limit-per-torrent
session-get	new arg seedRatioLimit
session-get	new arg seedRatioLimited
torrent-add	new arg files-unwanted
torrent-add	new arg files-wanted
torrent-add	new arg priority-high
torrent-add	new arg priority-low
torrent-add	new arg priority-normal
torrent-get	new arg bandwidthPriority
torrent-get	new arg fileStats
torrent-get	new arg honorsSessionLimits
torrent-get	new arg percentDone
torrent-get	new arg pieces
torrent-get	new arg seedRatioLimit
torrent-get	new arg seedRatioMode
torrent-get	new arg torrentFile
torrent-get	new ids option recently-active
torrent-reannounce	new method
torrent-set	new arg bandwidthPriority
torrent-set	new arg honorsSessionLimits
torrent-set	new arg seedRatioLimit
torrent-set	new arg seedRatioLimited

Transmission 1.70 (rpc-version-semver 2.1.0, rpc-version: 6)

Method	Description
method torrent-set-location	new method

Transmission 1.80 (rpc-version-semver 3.0.0, rpc-version: 7)

Method	Description
torrent-get	💣 removed arg announceResponse (use trackerStats instead)
torrent-get	💣 removed arg announceURL (use trackerStats instead)
torrent-get	💣 removed arg downloaders (use trackerStats instead)
torrent-get	💣 removed arg lastAnnounceTime (use trackerStats instead)
torrent-get	💣 removed arg lastScrapeTime (use trackerStats instead)
torrent-get	💣 removed arg leechers (use trackerStats instead)
torrent-get	💣 removed arg nextAnnounceTime (use trackerStats instead)
torrent-get	💣 removed arg nextScrapeTime (use trackerStats instead)
torrent-get	💣 removed arg scrapeResponse (use trackerStats instead)
torrent-get	💣 removed arg scrapeURL (use trackerStats instead)
torrent-get	💣 removed arg seeders (use trackerStats instead)
torrent-get	💣 removed arg swarmSpeed
torrent-get	💣 removed arg timesCompleted (use trackerStats instead)
session-set	new arg incomplete-dir-enabled
session-set	new arg incomplete-dir
torrent-get	new arg magnetLink
torrent-get	new arg metadataPercentComplete
torrent-get	new arg trackerStats

Transmission 1.90 (rpc-version-semver 3.1.0, rpc-version: 8)

Method	Description
session-set	new arg rename-partial-files
session-get	new arg rename-partial-files
session-get	new arg config-dir
torrent-add	new arg bandwidthPriority
torrent-get	new trackerStats arg lastAnnounceTimedOut

Transmission 1.92 (rpc-version-semver 3.2.0, rpc-version: 8)

Note: rpc-version was not bumped in this release due to an oversight.

Method	Description
torrent-get	new trackerStats arg lastScrapeTimedOut

Transmission 2.00 (rpc-version-semver 3.3.0, rpc-version: 9)

Method	Description
session-set	new arg start-added-torrents
session-set	new arg trash-original-torrent-files
session-get	new arg start-added-torrents
session-get	new arg trash-original-torrent-files
torrent-get	new arg isFinished

Transmission 2.10 (rpc-version-semver 3.4.0, rpc-version: 10)

Method	Description
session-get	new arg cache-size-mb
session-get	new arg units
session-set	new arg idle-seeding-limit-enabled
session-set	new arg idle-seeding-limit
torrent-set	new arg seedIdleLimit
torrent-set	new arg seedIdleMode
torrent-set	new arg trackerAdd
torrent-set	new arg trackerRemove
torrent-set	new arg trackerReplace

Transmission 2.12 (rpc-version-semver 3.5.0, rpc-version: 11)

Method	Description
session-get	new arg blocklist-url
session-set	new arg blocklist-url

Transmission 2.20 (rpc-version-semver 3.6.0, rpc-version: 12)

Method	Description
session-get	new arg download-dir-free-space
session-close	new method

Transmission 2.30 (rpc-version-semver 4.0.0, rpc-version: 13)

Method	Description
torrent-get	💣 removed arg peersKnown
session-get	new arg isUTP to the peers list
torrent-add	new arg cookies

Transmission 2.40 (rpc-version-semver 5.0.0, rpc-version: 14)

Method	Description
torrent-get	💣 values of status field changed
queue-move-bottom	new method
queue-move-down	new method
queue-move-top	new method
session-set	new arg download-queue-enabled
session-set	new arg download-queue-size
session-set	new arg queue-stalled-enabled
session-set	new arg queue-stalled-minutes
session-set	new arg seed-queue-enabled
session-set	new arg seed-queue-size
torrent-get	new arg fromLpd in peersFrom
torrent-get	new arg isStalled
torrent-get	new arg queuePosition
torrent-set	new arg queuePosition
torrent-start-now	new method

Transmission 2.80 (rpc-version-semver 5.1.0, rpc-version: 15)

Method	Description
torrent-get	new arg etaIdle
torrent-rename-path	new method
free-space	new method
torrent-add	new return arg torrent-duplicate

Transmission 3.00 (rpc-version-semver 5.2.0, rpc-version: 16)

Method	Description
session-get	new request arg fields
session-get	new arg session-id
torrent-get	new arg labels
torrent-set	new arg labels
torrent-get	new arg editDate
torrent-get	new request arg format

Transmission 4.0.0 (rpc-version-semver 5.3.0, rpc-version: 17)

Method	Description
/upload	⚠️ undocumented /upload endpoint removed
session-get	⚠️ DEPRECATED download-dir-free-space. Use free-space instead.
free-space	new return arg total_size
session-get	new arg default-trackers
session-get	new arg rpc-version-semver
session-get	new arg script-torrent-added-enabled
session-get	new arg script-torrent-added-filename
session-get	new arg script-torrent-done-seeding-enabled
session-get	new arg script-torrent-done-seeding-filename
torrent-add	new arg labels
torrent-get	new arg availability
torrent-get	new arg file-count
torrent-get	new arg group
torrent-get	new arg percentComplete
torrent-get	new arg primary-mime-type
torrent-get	new arg tracker.sitename
torrent-get	new arg trackerStats.sitename
torrent-get	new arg trackerList
torrent-set	new arg group
torrent-set	new arg trackerList
torrent-set	⚠️ DEPRECATED trackerAdd. Use trackerList instead.
torrent-set	⚠️ DEPRECATED trackerRemove. Use trackerList instead.
torrent-set	⚠️ DEPRECATED trackerReplace. Use trackerList instead.
group-set	new method
group-get	new method
torrent-get	⚠️ old arg wanted was implemented as an array of 0 or 1 in Transmission 3.00 and older, despite being documented as an array of booleans. Transmission 4.0.0 and 4.0.1 "fixed" this by returning an array of booleans; but in practical terms, this change caused an unannounced breaking change for any 3rd party code that expected 0 or 1. For this reason, 4.0.2 restored the 3.00 behavior and updated this spec to match the code.