Solana Chain Support

Extension Type: Chain Adaptation
Status: Draft
Version: 0.1.0
Authors: 8004scan Team

Overview

This extension defines how ERC-8004 standards apply to the Solana blockchain. Solana uses different address formats, signature algorithms, and NFT standards compared to EVM chains. This document covers the necessary adaptations for agent registration, feedback submission, and authentication on Solana.

1. Chain Identifiers

CAIP-2: Blockchain ID

Solana networks use the solana namespace with the first 32 bytes of the genesis block hash (base58-encoded) as the CAIP-2 reference:

text

solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp   → Solana Mainnet
solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1   → Solana Devnet

Note: Solana Testnet is not used in production.

CAIP-10: Account Address

Solana addresses are base58-encoded Ed25519 public keys (32 bytes, 32-44 characters):

text

solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp:Aqq2ZKnzXpsR4S18biMnJVEXVecgqU4Szi6rduszF8Sn
solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1:2KmHw8VbShuz9xfj3ecEjBM5nPKR5BcYHRDSFfK1286t

CAIP-10 for Program Addresses

Solana programs (equivalent to smart contracts) are referenced by their Program ID:

text

solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp:8oo48pya1SZD23ZhzoNMhxR2UGb8BRa41Su4qP9EuaWm

2. Agent Identity on Solana

NFT Standard: Metaplex Core

On Solana, ERC-8004 agents are represented as Metaplex Core assets instead of ERC-721 NFTs.

Concept	EVM (ERC-721)	Solana (Metaplex Core)
Token standard	ERC-721	Metaplex Core Asset
Canonical identifier	`tokenId` (uint256)	`asset` pubkey (base58)
Numeric identifier	`tokenId` (sequential)	`globalId` (sequential, indexer-assigned)
Contract/Program	Registry contract address	Program ID
Owner	`ownerOf(tokenId)`	Asset owner field
Metadata pointer	`tokenURI(tokenId)`	`agentURI` on-chain field
Collection	N/A	Metaplex Collection

Agent Registry Reference

text

# EVM format
eip155:84532:0x8004C269D0A5647E51E121FeB226200ECE932d55

# Solana format
solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp:8oo48pya1SZD23ZhzoNMhxR2UGb8BRa41Su4qP9EuaWm

The agent metadata file (Registration File) follows the same JSON schema as EVM agents. Only the registrations array entry differs.

Solana Agent Identifier Strategy

Solana agents have two identifiers that serve different purposes:

Identifier	Type	Source	Purpose
Asset pubkey (base58)	`string` (32-44 chars)	On-chain Metaplex Core asset	Canonical, immutable, globally unique
Global ID (numeric)	`bigint` (sequential)	Indexer DB sequence trigger	Display-compatible, EVM-compatible

Key points:

Asset pubkey is the canonical Solana agent identifier — it is the on-chain NFT address and is immutable once created.
Global ID (globalId / agentid in the indexer GraphQL) is a sequential auto-increment number assigned by the indexer's PostgreSQL trigger on agent creation. It provides EVM-compatible numeric addressing (e.g., #001, #042) for display and URL compatibility.
Global ID is stable once assigned (no shifting when new agents register), but not guaranteed consistent across independent indexer instances — re-indexing from scratch may re-assign numbers.
API endpoints and URLs SHOULD accept both formats and auto-detect:
- Numeric string → lookup by globalId / token_id
- Non-numeric string → lookup by asset pubkey / agent_id
Frontend URLs and display SHOULD prefer the base58 asset pubkey for Solana agents, truncating to 7-8 characters when space is limited (e.g., 84bgovN...).

GraphQL field mapping (indexer → backend):

Indexer GraphQL	Backend DB	Description
`agentid`	`token_id`	Sequential global ID (bigint)
`agentidFormatted`	—	Display format: `#001`, `#042`
`solana.assetPubkey`	`agent_id`	Base58 asset pubkey (canonical)
`agentId`	—	Legacy hash-derived uint64 (deprecated)

Note: The indexer also exposes agentId (camelCase), a hash-derived uint64 from the first 8 bytes of the asset pubkey. This field is deprecated — use agentid (lowercase) for numeric identifiers.

3. Address and Transaction Formats

Comparison Table

Property	EVM	Solana
Address encoding	Hex with `0x` prefix	Base58 (no prefix)
Address length	42 chars (`0x` + 40 hex)	32-44 chars (base58)
Raw address size	20 bytes	32 bytes
Case sensitivity	Case-insensitive (EIP-55 checksum optional)	Case-sensitive
Transaction hash	66 chars (`0x` + 64 hex)	87-88 chars (base58 signature)
Block identifier	Block number (uint64)	Slot number (uint64)

Validation Rules

Solana Address:

Base58-encoded string (alphabet: 123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz)
Decodes to exactly 32 bytes
Case-sensitive — do NOT apply .toLowerCase() or .toUpperCase()

Solana Transaction Signature:

Base58-encoded Ed25519 signature
87-88 characters
Decodes to 64 bytes

4. Content Hashing

Hash Algorithm Differences

Property	EVM (ERC-8004 v1)	Solana (SEAL v1)
Algorithm	Keccak-256	SHA-256
Output format	`0x` + 64 hex chars	64 hex chars (no prefix)
Output length	66 chars	64 chars
Hash chain	Simple content hash	Running digest chain

SEAL v1 (Solana Event Authenticity Layer)

Solana feedback uses SEAL v1 for tamper-proof hash chains:

text

feedback_hash = SHA-256(feedback_content)
running_digest = SHA-256(previous_digest + feedback_hash)

This creates an append-only, verifiable chain of feedback events per agent+client pair.

5. Authentication

Signature Algorithm

Property	EVM	Solana
Algorithm	ECDSA (secp256k1)	Ed25519
Signature format	`0x` + hex (130 chars)	Base58 (~88 chars)
Message signing	EIP-191 `personal_sign`	`signMessage` (raw bytes)
Smart wallet	ERC-1271 / ERC-6492	N/A (no smart wallets)

Message format for wallet authentication:

text

8004scan wants you to sign in with your Solana account:
Aqq2ZKnzXpsR4S18biMnJVEXVecgqU4Szi6rduszF8Sn

Sign this message to authenticate with 8004scan.

Nonce: a1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4

Verification uses Ed25519 VerifyKey from the wallet's public key.

6. Feedback on Solana

SEAL v1 Fields

Solana feedback includes additional fields from the SEAL v1 protocol:

Field	Type	Description
`value`	int64	Raw metric value
`valueDecimals`	uint8 (0-6)	Decimal places for value
`score`	uint8 (0-100)	ATOM trust-weighted score (optional)
`feedbackHash`	hex string	SHA-256 hash (64 chars, no `0x`)
`runningDigest`	bytes	Hash chain digest
`isRevoked`	boolean	Revocation status

ATOM Trust Metrics

The ATOM engine computes on-chain trust scores for agents:

Metric	Range	Description
`trustTier`	0-4	Overall trust level
`qualityScore`	0-10000	Feedback quality aggregate
`confidence`	0-10000	Statistical confidence
`riskScore`	0-100	Sybil/manipulation risk
`diversityRatio`	0-255	Unique reviewer diversity

These metrics are computed on-chain and available through the Solana indexer's GraphQL API as the solana extension on Agent and Feedback types.

7. Payment Proof Format

SOL Payment

json

{
  "proofOfPayment": {
    "fromAddress": "D9bMDMbJungXQrE8n6ZsM3r6ZQLFTzygmsQL7yzGMDHw",
    "toAddress": "2KmHw8VbShuz9xfj3ecEjBM5nPKR5BcYHRDSFfK1286t",
    "chainId": "5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "txSignature": "5piJm888s7beTTrB9JuCR5WFvNxXHN78C9ifGEokTucoQy5mb6bKg3e6Fkiv8RznZG2NmzENBWUru5yUGbqMiTMp",
    "amount": "1000000000",
    "currency": "SOL",
    "decimals": 9
  }
}

Note: Solana uses txSignature (base58, 87-88 chars) instead of txHash (hex, 66 chars). The amount is in lamports (1 SOL = 10^9 lamports).

SPL Token Payment

json

{
  "proofOfPayment": {
    "fromAddress": "D9bMDMbJungXQrE8n6ZsM3r6ZQLFTzygmsQL7yzGMDHw",
    "toAddress": "2KmHw8VbShuz9xfj3ecEjBM5nPKR5BcYHRDSFfK1286t",
    "chainId": "5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "txSignature": "53i5Ymuosn6RduaxLw8Bx1P8XMrnzBRj7EJKdmNLnMtmN9WL45gjzq3jRQupTfhBP7MEghM9TUkhTq3zWz8gkB74",
    "amount": "1000000",
    "currency": "USDC",
    "tokenMint": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "decimals": 6
  }
}

8. Cross-Chain Agent Registration

Agents can be registered on both EVM and Solana chains simultaneously. The registration file's registrations array includes entries for each chain:

json

{
  "name": "My Cross-Chain Agent",
  "registrations": [
    {
      "agentId": 42,
      "agentRegistry": "eip155:84532:0x8004C269D0A5647E51E121FeB226200ECE932d55"
    },
    {
      "agentId": 7,
      "agentRegistry": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp:8oo48pya1SZD23ZhzoNMhxR2UGb8BRa41Su4qP9EuaWm"
    }
  ]
}

The registrations array uses a uniform schema across all chains: agentId + agentRegistry (CAIP-10 string). On EVM, agentId is a sequential uint256 token ID. On Solana, the agentId in the registration file SHOULD be the numeric globalId (sequential auto-increment from the indexer) for cross-chain consistency. Implementations MUST also support resolving agents by base58 asset pubkey for native Solana addressing.

9. Implementation Notes

Address Normalization

python

# EVM: case-insensitive, normalize to lowercase
address = evm_address.lower()

# Solana: case-sensitive, DO NOT normalize
address = solana_address  # Keep as-is

Storage Considerations

Field	EVM Sizing	Solana Sizing	Recommended
Address	42 chars	44 chars	String(50)
Transaction hash	66 chars	88 chars	String(100)
Content hash	66 chars	64 chars	String(66) — fits both
Feedback ID	~40 chars	91 chars (composite)	String(150)

Validation Helper

python

import base58

def is_valid_solana_address(address: str) -> bool:
    """Validate Solana address: base58-encoded, decodes to 32 bytes."""
    try:
        decoded = base58.b58decode(address)
        return len(decoded) == 32
    except Exception:
        return False

10. References

CAIP-2 Specification
CAIP-10 Specification
Metaplex Core Documentation
ATOM Engine — On-chain trust scoring
SEAL v1 — Solana Event Authenticity Layer
Solana Genesis Hash (CAIP-2) — CAIP-2 namespace definition for Solana
Sign-In with Solana — Authentication standard

Solana Chain Support ​

Overview ​

1. Chain Identifiers ​

CAIP-2: Blockchain ID ​

CAIP-10: Account Address ​

CAIP-10 for Program Addresses ​

2. Agent Identity on Solana ​

NFT Standard: Metaplex Core ​

Agent Registry Reference ​

Solana Agent Identifier Strategy ​

3. Address and Transaction Formats ​

Comparison Table ​

Validation Rules ​

4. Content Hashing ​

Hash Algorithm Differences ​

SEAL v1 (Solana Event Authenticity Layer) ​

5. Authentication ​

Signature Algorithm ​

Sign-In with Solana (SIWS) ​

6. Feedback on Solana ​

SEAL v1 Fields ​

ATOM Trust Metrics ​

7. Payment Proof Format ​

SOL Payment ​

SPL Token Payment ​

8. Cross-Chain Agent Registration ​

9. Implementation Notes ​

Address Normalization ​

Storage Considerations ​

Validation Helper ​

10. References ​

Solana Chain Support

Overview

1. Chain Identifiers

CAIP-2: Blockchain ID

CAIP-10: Account Address

CAIP-10 for Program Addresses

2. Agent Identity on Solana

NFT Standard: Metaplex Core

Agent Registry Reference

Solana Agent Identifier Strategy

3. Address and Transaction Formats

Comparison Table

Validation Rules

4. Content Hashing

Hash Algorithm Differences

SEAL v1 (Solana Event Authenticity Layer)

5. Authentication

Signature Algorithm

Sign-In with Solana (SIWS)

6. Feedback on Solana

SEAL v1 Fields

ATOM Trust Metrics

7. Payment Proof Format

SOL Payment

SPL Token Payment

8. Cross-Chain Agent Registration

9. Implementation Notes

Address Normalization

Storage Considerations

Validation Helper

10. References