# MetaMask and Dual-Chain Provider Integration

The explorer (SolaceScanScout) provides add-to-MetaMask and token list discovery for **Chain 138** (DeFi Oracle Meta Mainnet), **Ethereum Mainnet**, and **ALL Mainnet** (651940).

## Explorer as discovery source

- **Add to MetaMask:** Use the [Wallet](/wallet) page to add Chain 138, Ethereum Mainnet, or ALL Mainnet to your wallet via `wallet_addEthereumChain`.
- **Token list URL:** The explorer API serves the dual-chain token list at:
  - **Path:** `/api/config/token-list`
  - **Full URL:** `{EXPLORER_API_BASE}/api/config/token-list` (e.g. `https://explorer.d-bis.org/api/config/token-list` if the API is on the same origin).
  Add this URL in MetaMask **Settings → Token lists** so tokens for Chain 138 and Mainnet appear automatically.
- **Networks config:** `/api/config/networks` returns the same chain params (Chain 138 + Ethereum Mainnet) in JSON for programmatic use.

## Provider and feature parity

- **Dual-chain provider:** For dApps that need add/switch chain, token list, and oracle helpers, use the [metamask-integration/provider](../../metamask-integration/provider) package. See [DUAL_CHAIN_PROVIDER_README.md](../../docs/04-configuration/metamask/DUAL_CHAIN_PROVIDER_README.md).
- **Feature parity (Swaps, Bridge, pricing):** MetaMask does not natively support Chain 138 for Swaps or Portfolio Bridge. For gaps and build/integration options (custom Snap, token-aggregation API, discovery via token list and liquidity pools), see [METAMASK_CHAIN138_FEATURE_PARITY_ANALYSIS.md](../../docs/04-configuration/metamask/METAMASK_CHAIN138_FEATURE_PARITY_ANALYSIS.md).

## Discovery without CMC/CoinGecko

Discovery is via **token list** (hosted at the explorer token list URL above), **liquidity pools** (token-aggregation service), and **pricing APIs** (token-aggregation REST API and on-chain oracles). See the feature parity doc for details.

**Token-aggregation REST API:** For tokens, pools, prices, volume, and OHLCV (Chain 138 and ALL Mainnet), see [smom-dbis-138/services/token-aggregation/docs/REST_API_REFERENCE.md](../../smom-dbis-138/services/token-aggregation/docs/REST_API_REFERENCE.md).

## Optional next steps

- **Custom MetaMask Snap:** For in-wallet swap quotes, bridge routes, and pricing on Chain 138, see [SNAP_IMPLEMENTATION_ROADMAP.md](../../docs/04-configuration/metamask/SNAP_IMPLEMENTATION_ROADMAP.md).
- **Feature parity and optional actions:** [METAMASK_CHAIN138_FEATURE_PARITY_ANALYSIS.md](../../docs/04-configuration/metamask/METAMASK_CHAIN138_FEATURE_PARITY_ANALYSIS.md) — Section 7 lists optional next steps (Snap, CoinGecko, Consensys outreach, market data API).

## Live explorer (https://explorer.d-bis.org)

- **Wallet page:** https://explorer.d-bis.org/wallet  
- **Token list URL:** https://explorer.d-bis.org/api/config/token-list  
- **Networks config:** https://explorer.d-bis.org/api/config/networks  

For backend deployment and integration tests, see [EXPLORER_D_BIS_ORG_INTEGRATION.md](../../docs/04-configuration/metamask/EXPLORER_D_BIS_ORG_INTEGRATION.md).

## Related

- [CHAINLIST_AND_METAMASK_DATA_FLOW.md](CHAINLIST_AND_METAMASK_DATA_FLOW.md) — Chainlist, MetaMask, and token list data flow.
- [Token list submission links](TOKEN_LIST_SUBMISSION_LINKS.md) — Uniswap token-lists and aggregators.