> ## Documentation Index
> Fetch the complete documentation index at: https://cosmos-docs-cosmjs-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Transaction Structure

> How Cosmos transactions are structured and how message type URLs work

A Cosmos transaction is a Protobuf-encoded envelope containing three parts:

```text theme={"system"}
+--------------------------------------------------+
|                      TxRaw                        |
+-----------------+------------------+--------------+
|  bodyBytes      |  authInfoBytes   |  signatures  |
|  (TxBody)       |  (AuthInfo)      |  (bytes[])   |
+--------+--------+---------+--------+--------------+
         |                  |
         v                  v
+----------------+  +-------------------------------+
|    TxBody      |  |           AuthInfo             |
+----------------+  +-------------------------------+
|  messages[]    |  |  signerInfos[]                 |
|  memo          |  |    - publicKey (Any)           |
|  timeoutHeight |  |    - modeInfo (SignMode)       |
|                |  |    - sequence                  |
|                |  |  fee                           |
|                |  |    - amount (Coin[])           |
|                |  |    - gasLimit                  |
|                |  |    - payer                     |
|                |  |    - granter                   |
+----------------+  +-------------------------------+
```

Each message inside `TxBody.messages` is wrapped in a `google.protobuf.Any` —
a two-field wrapper that pairs a **type URL** string with raw Protobuf **bytes**.
This is how the chain knows which message handler to route to.

## Message Type URLs

Every Cosmos SDK message has a unique identifier called a **type URL**. It
follows the Protobuf `Any` convention: a leading `/` followed by the fully
qualified Protobuf type name.

```text theme={"system"}
/cosmos.bank.v1beta1.MsgSend
 ^                    ^
 |                    +-- message name
 +-- package path (module.version)
```

Type URLs serve as the bridge between your JavaScript code and the on-chain
message router. When a validator receives a transaction, it reads the type URL
from each `Any`-wrapped message to determine which module should handle it.

### Common Type URLs

| Module           | Type URL                                                      | Description                        |
| ---------------- | ------------------------------------------------------------- | ---------------------------------- |
| **Bank**         | `/cosmos.bank.v1beta1.MsgSend`                                | Transfer tokens                    |
|                  | `/cosmos.bank.v1beta1.MsgMultiSend`                           | Transfer to multiple recipients    |
| **Staking**      | `/cosmos.staking.v1beta1.MsgDelegate`                         | Delegate to a validator            |
|                  | `/cosmos.staking.v1beta1.MsgUndelegate`                       | Begin unbonding                    |
|                  | `/cosmos.staking.v1beta1.MsgBeginRedelegate`                  | Move delegation between validators |
|                  | `/cosmos.staking.v1beta1.MsgCreateValidator`                  | Register a new validator           |
|                  | `/cosmos.staking.v1beta1.MsgEditValidator`                    | Edit validator details             |
|                  | `/cosmos.staking.v1beta1.MsgCancelUnbondingDelegation`        | Cancel pending unbonding           |
| **Distribution** | `/cosmos.distribution.v1beta1.MsgWithdrawDelegatorReward`     | Claim staking rewards              |
|                  | `/cosmos.distribution.v1beta1.MsgSetWithdrawAddress`          | Set reward withdrawal address      |
|                  | `/cosmos.distribution.v1beta1.MsgFundCommunityPool`           | Fund the community pool            |
|                  | `/cosmos.distribution.v1beta1.MsgWithdrawValidatorCommission` | Withdraw validator commission      |
| **Governance**   | `/cosmos.gov.v1.MsgSubmitProposal`                            | Submit a governance proposal (v1)  |
|                  | `/cosmos.gov.v1.MsgVote`                                      | Vote on a proposal (v1)            |
|                  | `/cosmos.gov.v1.MsgDeposit`                                   | Deposit on a proposal (v1)         |
|                  | `/cosmos.gov.v1beta1.MsgSubmitProposal`                       | Submit a proposal (legacy)         |
|                  | `/cosmos.gov.v1beta1.MsgVote`                                 | Vote on a proposal (legacy)        |
| **Authz**        | `/cosmos.authz.v1beta1.MsgGrant`                              | Grant authorization                |
|                  | `/cosmos.authz.v1beta1.MsgExec`                               | Execute on behalf of granter       |
|                  | `/cosmos.authz.v1beta1.MsgRevoke`                             | Revoke authorization               |
| **Fee Grant**    | `/cosmos.feegrant.v1beta1.MsgGrantAllowance`                  | Grant fee allowance                |
|                  | `/cosmos.feegrant.v1beta1.MsgRevokeAllowance`                 | Revoke fee allowance               |
| **Vesting**      | `/cosmos.vesting.v1beta1.MsgCreateVestingAccount`             | Create a vesting account           |
| **IBC**          | `/ibc.applications.transfer.v1.MsgTransfer`                   | Cross-chain token transfer         |
| **CosmWasm**     | `/cosmwasm.wasm.v1.MsgStoreCode`                              | Upload contract code               |
|                  | `/cosmwasm.wasm.v1.MsgInstantiateContract`                    | Create a contract instance         |
|                  | `/cosmwasm.wasm.v1.MsgExecuteContract`                        | Call a contract                    |
|                  | `/cosmwasm.wasm.v1.MsgMigrateContract`                        | Migrate a contract to new code     |