Multi Collateral Dai (MCD) CLI

Welcome to the MCD CLI

Installation

First install dapp tools:

$ curl https://dapp.tools/install | sh

Then install the mcd package:

$ dapp pkg install mcd

The following list details all of the commands available when interacting with the command-line interface:

MCD - Multi-collateral Dai

Usage: mcd [<options>] <command> [<args>]
   or: mcd help [<command>]

Commands:

   bite            Trigger liquidation of an unsafe Urn
   bites           Recent bites
   cdp             CDP managerment
   dai             Dai management
   debt            Total dai issuance
   drip            Trigger stability fee accumulation
   flap            Trigger a flap auction
   flips           View flips and kick-off auctions
   flog            Release queued bad-debt for auction
   flop            Trigger a flop auction
   frob            Urn management
   frobs           Recent frobs
   gem             Collateral management
   help            Print help about mcd or one of its subcommands
   ilk             Ilk (collateral type) parameters
   line            Total debt ceiling
   live            Liveness flag
   poke            Update the spot price for a given Ilk
   unwrap          Unwrap WETH to ETH
   urn             CDP state
   vice            Total bad debt
   vow             Liquidator balances
   wrap            Wrap ETH to WETH

Configuration

Mcd is built on Seth and uses the same network configuration options, which just like Seth, can be defined in the ~/sethrc initialisation file.

Similar to Seth, mcd also supports transaction signing with Ledger hardware wallets and can run against both local and remote nodes.

Since mcd will always be used against a known deployment of the system, defaults can be loaded wherever possible. In most cases the only required configuration parameter is the -C, --chain=<chain> (MCD_CHAIN) option and -F, --from=<address> (ETH_FROM) sender account when not using a testnet.

Example ~/.sethrc:

#!/usr/bin/env bash
export ETH_FROM=0x4Ffa8667Fe2db498DCb95A322b448eA688Ce430c
export MCD_CHAIN=kovan

Kovan

Run against the latest Kovan deployment by setting the -C, --chain option to kovan. Specify a sender account when sending transactions using the -F, --from option, or via the ETH_FROM env variable.

$ export ETH_FROM=0x4Ffa8667Fe2db498DCb95A322b448eA688Ce430c
$ mcd --chain=kovan dai join 100

Remote testchain

Run agaist remote testchain deployments by setting the -C, --chain option to the remote testchain Id. Mcd will auto-configure account settings via the testchain api so that no further configuration is required. To view a list of available testchains run:

$ mcd testnet chains`

Then set the chain option, or the chain env variable to the appropriate testchain Id.

$ export MCD_CHAIN=12899149080555595289
$ mcd dai join 100

Local testnet

Run against a locally running instance of Dapp testnet where the system has been deployed by setting the C, --chain option to testnet. Mcd will auto-configure account testings for dapp testnet so that no further configuration is required.

By default, Mcd assumes that the output of the testchain deployment script is available at ~/.dapp/testnet/8545/config/addresses.json. Configuration addresses can be loaded from a different location by setting the --config (MCD_CONFIG) option.

$ export MCD_CONFIG=~/testchain-deployment-scripts/out/addresses.json
$ mcd -C testnet dai join 100

Ilk

Ilks are collateral types with corresponding risk parameters which have been approved by system governance. Use the ilks command to view the list off available Ilks.

$ mcd ilks
ILK      GEM    DESC

ETH-A    WETH   Ethereum
ETH-B    WETH   Ethereum
REP-A    REP    Augur

Each Ilk has its own set of configuration parameters which can be viewed via the ilk command. The I, --ilk=<id> option is used to scope commands to a particular Ilk:

$ mcd --ilk=ETH-A ilk
Art  40.000000000000000000                      Total debt (DAI)
rate 1.000080370887129123082627939              WETH DAI exchange rate
spot 99.333333333333333333333333333             WETH price with safety mat (USD)
line 1000.0000000000000000000000000000000000000 Debt ceiling (DAI)
dust 0.0000000000000000000000000000000000000000 Debt floor (DAI)
flip 0x9d905effff127a01da3b38124f8da88e766eb8dd Flip auction contract
chop 1.000000000000000000000000000              Liquidation penalty
lump 10000.000000000000000000                   Flip auction lot size
tax  1.000000000782997609082909351              Stability fee
rho  1552802862                                 Last drip timestamp
pip  0x98312e16f5b2c0def872a1f7484a8456e5a67a3b Price feed contract
mat  1.500000000000000000000000000              Liquidation ratio

Individial ilk values can be retrieved by adding the parameter name as an argument to the ilk command:

$ mcd --ilk=ETH-A ilk spot
99.333333333333333333333333333

Gem

Gems are collateral tokens. Collateral is added and removed from the via adapters, which abstract away the differences between various token behaviours. Use gem [<subcommand>] to manage collateral balances for any given Ilk.

gem --ilk=<id> symbol             Gem symbol e.g. WETH
gem --ilk=<id> balance            Print balances for a given urn (default: ETH_FROM)
gem --ilk=<id> join <wad>         Add collateral to a given Urn (default: ETH_FROM)
gem --ilk=<id> exit <wad> [<guy>] Remove collateral from an Urn (default: ETH_FROM)

The join command can add collateral from the sender account to any specified Urn. The exit command can remove collateral from a specified Urn, provided that the sender controls the private key associated with that Urn.

By default, ETH_FROM is used to determine which Urn should be credited with collateral. Use U, --urn=<address> to optionally credit an Urn other than the default.

$ mcd --ilk=ETH-A --urn=0x123456789abcdef0123456789abcdef012345678 join 100

The exit command can remove collateral from a specified Urn, provided that the sender controls the private key associated with that Urn. The exit command can also withdraw collateral to an account other than ETH_FROM buy passing the destination address as an additional argument:

$ mcd --ilk=ETH-A exit 100 0xDecaf00000000000000000000000000000000000

Urn

Urns represent Cdp state for any given Urn address.

Use the urn command to view Urn state for any given Ilk:

ilk  ETH-A                                      Collateral type
urn  0xC93C178EC17B06bddBa0CC798546161aF9D25e8A Urn handler
ink  45.000000000000000000                      Locked collateral (WETH)
art  120.000000000000000000                     Issued debt (Dai)
tab  120.000244107582797248312544980            Outstanding debt (Dai)
rap  0.000244107582797248312544980              Accumulated stability fee (Dai)
-->  37.24                                      Collateralization ratio

spot 99.333333333333333333333333333             WETH price with safety mat (USD)
rate 1.000002034229856643749638820              WETH DAI exchange rate

By default, ETH_FROM is used to determine which Urn to query. Use the U, --urn=<address> option to query Urns at other indexes.

Urn management

Urn state (urn.ink and urn.art) is managed via the frob <dink> <dart> command, where dink and dart are delta amounts by which ink (Locked collateral) and art (Outstanding debt) should be changed. For example, to lock 100 WETH and draw 400 Dai on the ETH-A Ilk:

$ mcd --ilk=ETH-A frob 100 400

To reduce outstanding debt by 200 Dai whilst keeping the amount of locked collateral constant:

$ mcd --ilk=ETH-A frob -- 0 -200

Dai

Similar to Gem adapters, a Dai adapter is used to exchange Vat Dai for ERC20 token Dai which can then be used outside the system. Use dai [<subcommand>] to manage dai balances.

dai balance    Print balances for a given urn (default: ETH_FROM)
dai join <wad> Exchange DSToken Dai for Vat Dai
dai exit <wad> Exchange Vat Dai for DSToken Dai

Once Dai has been drawn on an Urn, it can be withdrawn for use outside the system using dai exit. Dai can be returned to repay Urn debt via dai join.

The dai balance command displays the internal system (vat) balance and the external (ext) token balance:

$ mcd dai balance
vat 1030.003120998308631176024235912000000000000000000 Vat balance
ext 0.000000000000000000 ERC20 balance

Individial balance values can be retrieved by adding vat or ext as an argument to the balance command:

$ mcd dai balance vat
1030.003120998308631176024235912000000000000000000

Cdp

The cdp command provides compatability with CDPs managed via the CDP Portal and uses the same proxy contract and Cdp Manager font-end. This allows CDPs to be managed via a unique integer identifier rather than the I, --ilk and U, --urn options.

Usage: mcd cdp [<id>] [<command>]

Commands: ls [<owner>]     List Cdps
          count [<owner>]  Cdp count
          open             Open a new Cdp
          <id> urn         Cdp state
          <id> lock <wad>  Join & lock collateral
          <id> free <wad>  Free & exit collateral
          <id> draw <wad>  Draw & exit dai
          <id> wipe <wad>  Join & wipe dai

Examples

Note: examples assume that ETH_FROM is set to an address controlled by the user, and that the MCD_CHAIN env variable has been set to a vaild chain identifier.

1. Native Urn - lock 100 ETH & draw 500 Dai

Note: The system doesn't handle ETH directly but instead uses WETH to represent ETH collateral. For convenience, the wrap and unwrap commands are provided for exchanging ETH to WETH and visa versa.

# i) Wrap
$ mcd wrap 100
eth  900.000000000000000000
weth 100.000000000000000000

# ii) Gem join
$ mcd --ilk=ETH-A gem join 100
$ Grant approval to move WETH to the Vat? [Y/n]: Y
vat 100.000000000000000000 Free collateral (WETH)
ink   0.000000000000000000 Locked collateral (WETH)
ext   0.000000000000000000 External account balance (WETH)
ext 900.000000000000000000 External account balance (ETH)

# iii) Lock & Draw
$ mcd --ilk=ETH-A frob 100 500
ilk  ETH-A                                      Collateral type
urn  0xC93C178EC17B06bddBa0CC798546161aF9D25e8A Urn handler
ink  100.000000000000000000                     Locked collateral (WETH)
art  500.000000000000000000                     Issued debt (Dai)
tab  500.000244107582797248312544980            Outstanding debt (Dai)
rap  0.000244107582797248312544980              Accumulated stability fee (Dai)
-->  19.86                                      Collateralization ratio

# iv) Withdraw Dai
$ mcd dai exit 500
vat 0.000060682318362511884962000000000000000000000 Vat balance
ext 500.000000000000000000 ERC20 balance

2. Managed Cdp - lock 100 REP & draw 50 Dai

# i) Open
$ mcd --ilk=REP-A cdp open
mcd-cdp-open: Waiting for transaction receipt...
0x800e5578d3ac4b77b7ada1aba48cf80d0d238d4392d2676d79159eac2c2cdd73
Opened: cdp 19

# ii) Lock
$ mcd --ilk=REP-A cdp 19 lock 100
seth-send: Published transaction with 260 bytes of calldata.
seth-send: 0x4d30cb4863ca997d24ff2346c9a92e86648369ce7b4a86ed004c73b8d4ef299a
seth-send: Waiting for transaction receipt...
seth-send: Transaction included in block 333.
ilk  REP-A                                      Collateral type
urn  0x4518c4709a50C915b7996A0e6Dfb38c67248BBcF Urn handler
ink  100.000000000000000000                     Locked collateral (REP)
art  0.000000000000000000                       Issued debt (Dai)
tab  0                                          Outstanding debt (Dai)
rap  0                                          Accumulated stability fee (Dai)
-->  0                                          Collateralization ratio

# iii) Draw
$ mcd --ilk=REP-A cdp 19 draw 500
seth-send: Published transaction with 260 bytes of calldata.
seth-send: 0xd5fb7ddf94bb910fbba2af118ecde88a03a13129b2e1979238236afe672781c3
seth-send: Waiting for transaction receipt...
seth-send: Transaction included in block 335.
ilk  REP-A                                      Collateral type
urn  0x4518c4709a50C915b7996A0e6Dfb38c67248BBcF Urn handler
ink  100.000000000000000000                     Locked collateral (REP)
art  49.999505439113270178                      Issued debt (Dai)
tab  50.000000000000000000000000000             Outstanding debt (Dai)
rap  0.000494560886729822000020743              Accumulated stability fee (Dai)
-->  16.66                                      Collateralization ratio