Arb RWA flow listen tool: mint / PairCreated

Arbitrum official frames the tape around RWA deployments + stablecoin flow—this post watches mint / Transfer / PairCreated on one panel: contract mints, size Transfers, fresh pools. Base stock-token Swap watch watches whitelist big prints; here we watch the Arb RWA / stablecoin flow layer.

Run on the public endpoint · blockreq.com register for 3M free requests monthly.

Use	Endpoint
Public HTTPS	https://arbitrum-one-rpc.blockreq.com/v1/rpc/public
Public WSS	wss://arbitrum-one-rpc.blockreq.com/v1/rpc/public
Private	Trailing public → {API_KEY} (keys stay local)

Chain: Arbitrum One EVM chainId = 0xa4b1 (42161). Public endpoints · eth_subscribe · Plans · Register.

1. Hook: RWA flow × three subscriptions

Tape feel	On-chain signal	Watch
RWA mint	ERC20 Transfer · from = zero	mint size · contract
Stablecoin flow	Transfer amount ≥ threshold	USD notionals / raw amounts
Pool open	Factory PairCreated	token0 / token1 ∈ RWA·stable tables
Flow panel	three lanes → one screen	Dedupe = txHash + logIndex

Same family, different grain: Base stock-token converges on Swap big prints; this Arb post converges on mint + Transfer + PairCreated flow cards.

2. Event: mint / Transfer / PairCreated

Keep local JSON RWA_TOKEN_LIST + STABLE_LIST + FACTORY_LIST + MIN_TRANSFER_*. One Arb public WSS: subscribe three log lanes in parallel, decode into flowState.

Step A · Subscribe Transfer (mint when from = zero)

{
  "jsonrpc": "2.0", "id": 1, "method": "eth_subscribe",
  "params": ["logs", {
    "address": ["RWA_OR_STABLE_LIST"],
    "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]
  }]
}

• topics[0]: ERC20 Transfer(address,address,uint256).
• topics[1] (from) = 0x000…000 → tag mint; size ≥ threshold → large flow.

Step B · Subscribe Factory PairCreated (parallel OK)

{
  "jsonrpc": "2.0", "id": 2, "method": "eth_subscribe",
  "params": ["logs", {
    "address": ["FACTORY_LIST"],
    "topics": ["0x0d3648bd0f6ba80134a33ba9275ac585d9d315f0ad8355cddefde31afa28d0e9"]
  }]
}

• Decode token0 / token1 / pair → either side ∈ RWA_TOKEN_LIST ∪ STABLE_LIST → pool-open card.

Step C · Flow card fields

{ chain: "arbitrum-one", pad: "rwa-flow", kind: "mint|transfer|pair", token, amount, counterparty, pair, factory, txHash, blockNumber, ts }

Dedupe on txHash + logIndex; demo knobs: thresholds and address tables.

3. Browser demo (StackBlitz)

Default Arbitrum One public WSS; paste RWA / stablecoin / Factory tables + Transfer threshold, hit Start, stream flow cards. Code lives in StackBlitz — the post only embeds the preview:

Repo: blockreq/blog-demos → examples/arbitrum-rwa-flow-listen.

Product page: ZH · EN

WSS  → wss://arbitrum-one-rpc.blockreq.com/v1/rpc/public
HTTPS→ https://arbitrum-one-rpc.blockreq.com/v1/rpc/public
env  → RWA_TOKEN_LIST · STABLE_LIST · FACTORY_LIST · MIN_TRANSFER_USD · MIN_RAW

Keyed: swap trailing public for {API_KEY}. Quota: blockreq.com register for 3M free requests monthly.

4. Alert rhythm

1. log arrives → route mint / Transfer / PairCreated.
2. Table + threshold → contract ∈ tables; Transfer size clears the bar; Pair sides hit RWA·stable.
3. Outbound → Arb RWA flow · kind=… · token=… · amt=… · blk=….
4. Dedupe → one push per txHash + logIndex.

On disconnect: reconnect and re-subscribe; gap-fill with HTTPS eth_getLogs on the same address set. POST → https://arbitrum-one-rpc.blockreq.com/v1/rpc/public.

5. Summary + CTA

1. Grain: Arb RWA watch = mint / Transfer / PairCreated flow.
2. Recipe: address tables + Transfer topic + Factory PairCreated + size threshold → flow card.
3. Runnable: browser on BlockReq Arbitrum One public WSS; demos1 paths above.
4. Start: Public endpoints + blockreq.com register for 3M free requests monthly.

Next: pin RWA / stablecoin / Factory JSON → webhook → stack on-screen with Base stock-token Swap print cards. Docs · Pricing · Register.