Appendix A - MsgPack Reference

In the go-algorand reference implementation, all data structures that are exchanged between components of the Algorand node are annotated to specify how they should be encoded.

The Algorand Cryptographic specification defines the encoding rules for each type using a canonical variant of MessagePack.

Additional details about how encoding works in the Algorand Node can be found in the go-algorand MessagePack documentation.

Here are some important rules used by the codec:

• If a struct includes the special field \_struct struct{}, then all codec options (such as omitempty, omitemptyarray, etc.) apply to each field within that struct.

• The first part of the codec tag string specifies the field name to use in the encoded output. If this name is omitted (e.g., codec:"," or codec:",..."), the field will be encoded using its original Go field name.

For a broader understanding of the msgpack format in Go, refer to this primer.