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

# Shared Types

> Common types used across all Protochain gRPC services.

These types appear as fields in request and response messages across multiple Protochain services. Each type is documented once here so method pages can link back rather than repeating definitions.

## CommitmentLevel

`protochain.solana.type.v1.CommitmentLevel`

CommitmentLevel controls which version of the ledger state a query reads from. Solana validators process blocks in three stages — processed, confirmed, finalized — each representing a higher degree of cluster consensus.

When a method accepts an optional `commitment_level` field, omitting it or passing `COMMITMENT_LEVEL_UNSPECIFIED` lets the service use its default (typically `COMMITMENT_LEVEL_CONFIRMED`).

<ResponseField name="COMMITMENT_LEVEL_UNSPECIFIED" type="enum value = 0">
  Not set. The service uses its default commitment level, which is `COMMITMENT_LEVEL_CONFIRMED` unless otherwise documented. Use this when you have no specific latency or finality requirements.
</ResponseField>

<ResponseField name="COMMITMENT_LEVEL_PROCESSED" type="enum value = 1">
  The transaction has been processed by the leader and included in a block, but the block has not yet been confirmed by the cluster. **Use when:** you need the absolute lowest latency and can tolerate the possibility that the block gets dropped. Not suitable for anything involving fund movements.
</ResponseField>

<ResponseField name="COMMITMENT_LEVEL_CONFIRMED" type="enum value = 2">
  The block containing the transaction has been confirmed by a supermajority of the cluster. **Use when:** you need a good balance of speed and reliability — the default for most operations. Appropriate for reading account balances, checking transaction status during interactive flows.
</ResponseField>

<ResponseField name="COMMITMENT_LEVEL_FINALIZED" type="enum value = 3">
  The block has been rooted (finalized) by the cluster. This block cannot be rolled back. **Use when:** funds must be irreversibly settled before proceeding — for example, confirming a deposit before crediting a user account. This is the slowest option; finality on Solana typically takes 32+ slots (\~13 seconds) after confirmation.
</ResponseField>

***

## TokenProgram

`protochain.solana.type.v1.TokenProgram`

TokenProgram identifies which Solana token program an operation targets. SPL Token (`LEGACY`) and Token-2022 (`2022`) are **incompatible** — a mint created with one program cannot be used with the other. You must use the correct program for all operations involving a given token.

<Warning>
  `TOKEN_PROGRAM_UNSPECIFIED` is not a valid value. Services return an error if this value is received. Always specify either `TOKEN_PROGRAM_LEGACY` or `TOKEN_PROGRAM_2022`.
</Warning>

<ResponseField name="TOKEN_PROGRAM_UNSPECIFIED" type="enum value = 0">
  Invalid. Do not use. Services return an error when this value is received.
</ResponseField>

<ResponseField name="TOKEN_PROGRAM_LEGACY" type="enum value = 1">
  The original SPL Token program (`spl-token`, program address `TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA`). The majority of existing Solana tokens use this program. **Use when:** you are working with existing SPL tokens or building for maximum ecosystem compatibility.
</ResponseField>

<ResponseField name="TOKEN_PROGRAM_2022" type="enum value = 2">
  The Token Extensions program (`spl-token-2022`, program address `TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb`), also known as Token-2022. Supports extensions: transfer fees, interest-bearing tokens, non-transferable tokens, confidential transfers, and more. **Use when:** you need Token-2022 extensions, or are creating new tokens and want access to the full extension model.
</ResponseField>

***

## KeyPair

`protochain.solana.type.v1.KeyPair`

A Solana cryptographic key pair used for transaction signing. Returned by `GenerateNewKeyPair` and accepted by `SignTransaction`.

<Warning>
  The `private_key` field is transmitted in plaintext over gRPC. Use TLS in production. Never log or store `private_key` values.
</Warning>

<ResponseField name="public_key" type="string" required>
  Base58-encoded Ed25519 public key. This is the account address on Solana.
</ResponseField>

<ResponseField name="private_key" type="string" required>
  Hex-encoded Ed25519 private key (32 bytes = 64 hex characters). Used to sign transactions.
</ResponseField>