> For the complete documentation index, see [llms.txt](https://ston-fi.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ston-fi.gitbook.io/docs/developer-section/dex/smart-contracts/v2/examples/lp-provide.md).
# LP Provide Examples
## Deposit liquidity (both tokens)
Liquidity provision is done via 2 transactions: deposit of the first token and deposit of the second token.
### Deposit of the first token
The amount of the first token sent is stored on a user's lp account awaiting a transaction of the second token.
```mermaid
flowchart LR
A0(("Bob"))
A1["Bob
Token1
Wallet"]
A2["Router
Token1
Wallet"]
A3{"Router"}
A4(["Pool
Token1-Token2"])
A5[["Bob
Token1-Token2
Lp Account"]]
A0 --> |index: 0
op::transfer|A1
A1 --> |index: 1
op::internal_transfer|A2
A2 --> |index: 2
op::transfer_notification|A3
A2 -.-> |index: 3
op::excesses|A0
A3 --> |index: 4
op::provide_lp|A4
A4 --> |index: 5
op::add_liquidity|A5
A5 -.-> |index: 6
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#0400f0,color:#0400f0
```
### Deposit of the second token
When the second token is sent, lp account automatically initiates liquidity addition into the pool. As a result, full amounts of deposited tokens are used as new liquidity and the user receives lp tokens.
```mermaid
flowchart LR
A0(("Bob"))
A1["Bob
Token2
Wallet"]
A2["Router
Token2
Wallet"]
A3{"Router"}
A4(["Pool
Token1-Token2"])
A5[["Bob
Token1-Token2
Lp Account"]]
A6["Bob
Token1-Token2
Lp Wallet"]
A0 --> |index: 0
op::transfer|A1
A1 --> |index: 1
op::internal_transfer|A2
A2 --> |index: 2
op::transfer_notification|A3
A2 -.-> |index: 3
op::excesses|A0
A3 --> |index: 4
op::provide_lp|A4
A4 --> |index: 5
op::add_liquidity|A5
A5 -.-> |index: 6
op::cb_add_liquidity|A4
A4 --> |index: 7
op::internal_transfer|A6
A6 -.-> |index: 8
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#02dbdb,color:#02dbdb
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#0400f0,color:#0400f0
```
**Notes:**
* the `Lp Account` contract is deleted on `cb_add_liquidity` in order to not pay storage fees (each deposit sends state init so it will be redeployed as soon as any new deposit occurs)
* when depositing initial liquidity `0.000001001` lp tokens will be reserved on pool, the rest of liquidity will be sent to the user
## Deposit liquidity (single side provision)
It is possible to deposit liquidity by sending just 1 type of token, the pool will automatically perform a swap and use the resulting amount to mint lp tokens
```mermaid
flowchart LR
A0(("Bob"))
A1["Bob
Token1
Wallet"]
A2["Router
Token1
Wallet"]
A3{"Router"}
A4(["Pool
Token1-Token2"])
A5[["Bob
Token1-Token2
Lp Account"]]
A6["Bob
Token1-Token2
Lp Wallet"]
A0 --> |index: 0
op::transfer|A1
A1 --> |index: 1
op::internal_transfer|A2
A2 --> |index: 2
op::transfer_notification|A3
A2 -.-> |index: 3
op::excesses|A0
A3 --> |index: 4
op::provide_lp|A4
A4 --> |index: 5
op::add_liquidity|A5
A5 -.-> |index: 6
op::cb_add_liquidity|A4
A4 --> |index: 7
op::internal_transfer|A6
A6 -.-> |index: 8
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#02dbdb,color:#02dbdb
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#0400f0,color:#0400f0
```
## Deposit liquidity (with payload)
It is possible to specify who will receive lp tokens and to include a payload which will be sent as `transfer_notification` (e.g. `Farm` contract)
```mermaid
flowchart LR
A0(("Alice"))
A1["Alice
Token1
Wallet"]
A2["Router0
Token1
Wallet"]
A3{"Router0"}
A4(["Pool0
Token1-Token2"])
A5[["Alice
Token1-Token2
Lp Account0"]]
A6["SomeContract
Token1-Token2
Lp Wallet0"]
A7(("SomeContract"))
A0 --> |index: 0
op: transfer|A1
A1 --> |index: 1
op: internal_transfer|A2
A2 --> |index: 2
op: transfer_notification|A3
A2 -.-> |index: 3
op: excesses|A0
A3 --> |index: 4
op: provide_lp|A4
A4 --> |index: 5
op: add_liquidity|A5
A5 -.-> |index: 6
op: cb_add_liquidity|A4
A4 --> |index: 7
op: internal_transfer|A6
A6 --> |index: 8
op: transfer_notification|A7
A6 -.-> |index: 9
op: excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#02dbdb,color:#02dbdb
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#ff4747,color:#ff4747
linkStyle 9 stroke:#0400f0,color:#0400f0
```
## Refund deposited liquidity
In the event that the issued amount of lp tokens doesn't match the specified minimum value, all deposited liquidity is returned to lp account and can be withdrawn by user.
### Liquidity is refunded to lp account
```mermaid
flowchart LR
A0(("Bob"))
A1["Bob
Token2
Wallet"]
A2["Router
Token2
Wallet"]
A3{"Router"}
A4(["Pool
Token1-Token2"])
A5[["Bob
Token1-Token2
Lp Account"]]
A0 --> |index: 0
op::transfer|A1
A1 --> |index: 1
op::internal_transfer|A2
A2 --> |index: 2
op::transfer_notification|A3
A2 -.-> |index: 3
op::excesses|A0
A3 --> |index: 4
op::provide_lp|A4
A4 --> |index: 5
op::add_liquidity|A5
A5 -.-> |index: 6
op::cb_add_liquidity|A4
A4 --> |index: 7
op::add_liquidity|A5
A5 -.-> |index: 8
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#02dbdb,color:#02dbdb
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#0400f0,color:#0400f0
```
### Withdraw refunded liquidity
```mermaid
flowchart LR
A0(("Bob"))
A1[["Bob
Token1-Token2
Lp Account"]]
A2(["Pool
Token1-Token2"])
A3{"Router"}
A4["Router
Token2
Wallet"]
A5["Router
Token1
Wallet"]
A6["Bob
Token2
Wallet"]
A7["Bob
Token1
Wallet"]
A0 --> |index: 0
op::refund_me|A1
A1 --> |index: 1
op::cb_refund_me|A2
A2 --> |index: 2
op::pay_to|A3
A2 --> |index: 3
op::pay_to|A3
A3 --> |index: 4
op::transfer|A4
A3 --> |index: 5
op::transfer|A5
A4 --> |index: 6
op::internal_transfer|A6
A5 --> |index: 7
op::internal_transfer|A7
A6 -.-> |index: 8
op::excesses|A0
A7 -.-> |index: 9
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#ff4747,color:#ff4747
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#ff4747,color:#ff4747
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#0400f0,color:#0400f0
linkStyle 9 stroke:#0400f0,color:#0400f0
```
## Withdraw liquidly
Liquidly is withdrawn from a pool by burning lp tokens, a user then receives both pool tokens based on the current exchange rate.
```mermaid
flowchart LR
A0(("Bob"))
A1["Bob
Token1-Token2
Lp Wallet"]
A2(["Pool
Token1-Token2"])
A3{"Router"}
A4["Router
Token2
Wallet"]
A5["Router
Token1
Wallet"]
A6["Bob
Token2
Wallet"]
A7["Bob
Token1
Wallet"]
A0 --> |index: 0
op::burn|A1
A1 --> |index: 1
op::burn_notification_ext|A2
A2 --> |index: 2
op::pay_to|A3
A2 --> |index: 3
op::pay_to|A3
A3 --> |index: 4
op::transfer|A4
A3 --> |index: 5
op::transfer|A5
A4 --> |index: 6
op::internal_transfer|A6
A5 --> |index: 7
op::internal_transfer|A7
A6 -.-> |index: 8
op::excesses|A0
A7 -.-> |index: 9
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#ff4747,color:#ff4747
linkStyle 4 stroke:#ff4747,color:#ff4747
linkStyle 5 stroke:#ff4747,color:#ff4747
linkStyle 6 stroke:#ff4747,color:#ff4747
linkStyle 7 stroke:#ff4747,color:#ff4747
linkStyle 8 stroke:#0400f0,color:#0400f0
linkStyle 9 stroke:#0400f0,color:#0400f0
```
## Providing already deposited liquidity
A user can deposit liquidity after it was refunded to lp account without doing a withdraw.
```mermaid
flowchart LR
A0(("Bob"))
A1[["Bob
Token1-Token2
Lp Account"]]
A2(["Pool
Token1-Token2"])
A3["Bob
Token1-Token2
Lp Wallet"]
A0 --> |index: 0
op::direct_add_liquidity|A1
A1 --> |index: 1
op::cb_add_liquidity|A2
A2 --> |index: 2
op::internal_transfer|A3
A3 -.-> |index: 3
op::excesses|A0
linkStyle 0 stroke:#ff4747,color:#ff4747
linkStyle 1 stroke:#ff4747,color:#ff4747
linkStyle 2 stroke:#ff4747,color:#ff4747
linkStyle 3 stroke:#0400f0,color:#0400f0
```