Documented Shannon → Hideki USDso bridge route reverts during gas-quote preflight

Severity: normal
Area: SDK
Status: reproduced read-only; not submitted or accepted

Summary

The documented Shannon → Hideki2 USDso bridge route cannot currently complete its advertised gas-quote preflight. On 2026-10-31, the SDK's Shannon USDso router reverted on quoteGasPayment(50383) while the other four Shannon routers returned zero at the same block. The USDso router alone has a nonzero configured hook. Its public interface strongly matches Hyperlane's TestRecipient, which does not implement the required post-dispatch hook interface.

This is a reproducible deployed-route/docs discrepancy. The precise configuration cause is an inference pending operator verification. This report does not establish that all ways to fund Hideki are unavailable.

Context and impact

Perp developers using a dedicated EOA need native STT and USDso on Hideki2. The SDK registry's USDso destination token, 0xed7993A74dAe1e6656B704A424DcD8711aAf4F72, is exactly the collateral returned by the current Hideki MarginBank's getSystemConfig().

The official bridge guide lists USDso as live, uses USDso in its exchange bridge example, and says every router returns a zero gas quote. A client that implements the documented preflight encounters an empty revert instead. A client that assumes the documented zero quote can approve tokens before discovering a later dispatch failure. Our validation stopped before approving or broadcasting.

The public mint on Shannon succeeds in simulation, so the failure is distinct from the separate voucher-claim eligibility problem already reported by other developers.

Environment

Retained evidence

• Block-pinned quote, hook, and enrollment responses.
• Supplementary zero-amount simulations and hook selector scan.
• Two-chain funding prerequisites and public USDso mint simulation.
• Alternative WETH mint and Hideki spot liquidity probes.

Reproduction

The accompanying scripts/repro-bridge-quote.mjs uses only eth_chainId, eth_getBlockByNumber, and eth_call. It needs Node 24 and public network access. It does not load a key, sign, send a transaction, approve a token, claim funds, or alter chain state.

NODE_USE_ENV_PROXY=1 node scripts/repro-bridge-quote.mjs

By default the script selects the latest block, then pins every quote, hook, and enrollment read to it. Use --block 528513052 to reproduce the retained observation on a node that still serves that historical block.

The expectedFailureObserved field is true only when USDso returns the recorded empty revert, all four controls return zero and the block hash remains unchanged. A false result can mean the route has changed; retain the full responses.

All quote, hook, and enrollment reads are pinned to one source block. The script checks that block's hash again before returning. Run it without NODE_USE_ENV_PROXY=1 if your environment does not use an outbound proxy.

The minimal failing JSON-RPC call is:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_call",
  "params": [
    {
      "to": "0x94E2E7f4B2B0a8E3032c7D3ff3c86790BB5979E6",
      "data": "0xf2ed8c53000000000000000000000000000000000000000000000000000000000000c4cf"
    },
    "latest"
  ]
}

Observed response:

{"jsonrpc":"2.0","id":1,"error":{"code":3,"message":"execution reverted","data":"0x"}}

Adding a fresh EOA as from gives the same result. This quote does not require a token balance or allowance.

Expected and observed results

All five source routes remain enrolled. USDso's routers(50383) returns the expected destination router. The inverse destination enrollment also matches the source router. This rules out an obvious missing enrollment as the explanation for the quote failure.

As a supplementary diagnostic at block 528509576 (hash 0x3467e6161413cedcd9628abc2d50473ea580c50fa954a8e5b2751512f6da5311), zero-amount transferRemote calls were simulated with eth_call from the same fresh EOA. STT, WBTC, WETH, and HBTT returned message IDs; USDso reverted. These were zero-amount simulations, not live dispatches or positive-amount bridge tests.

Diagnostic inference: incompatible hook

The deployed hook bytecode exposes these ten selectors, all matching the official Hyperlane TestRecipient source and its inherited ownership methods:

The bytecode selector scan did not find hookType(), quoteDispatch(bytes,bytes), or postDispatch(bytes,bytes). hookType() also reverts in a direct call. TestRecipient does not implement the post-dispatch hook interface. Hyperlane's GasRouter.quoteGasPayment uses the configured hook in its quote path.

This makes an incompatible configured hook a strong explanation. We have not established a byte-for-byte compiler match or traced a positive-amount transfer, so the report should not label the inferred contract identity as proven.

Suggested resolution

1. Operators should verify the source USDso router's configured hook and restore a supported hook or the intended default, if the current address is unintended.
2. Add the USDso gas quote and hook-interface check to the live bridge health check. Return a route-specific unavailable status when preflight fails.
3. The SDK's execution path should obtain a current quote and stop before token approval if that quote fails. Static registry availability is not evidence that a deployed route is currently executable.
4. Update the bridge documentation to distinguish deployment-time verification from current route health, and explain the initial Shannon gas requirement for dedicated perp EOAs.

Sources

The SDK revision is npm release 0.32.1 (the exact version pinned in this repository). Hyperlane interface comparisons are pinned to commit 0063de628aeddfd5fecec6ca4719f7944223c1bd, dated 2026-10-30. These sources describe the expected interface, not proof of the deployed hook's compiler identity.

• Official current bridge guide: https://prd.smk.somnia.host/docs/typescript/bridge
• Official chains walkthrough: https://prd.smk.somnia.host/docs/typescript/chains-walkthrough
• Official token funding guide: https://prd.smk.somnia.host/docs/typescript/how-to/get-testnet-funds
• Official perp network and collateral: https://app.testnet.dreamdex.io/docs/developers/perps-testnet
• Published SDK package: https://www.npmjs.com/package/@somnia-chain/markets-sdk/v/0.32.1. src/chains/bridge/registry.ts, src/chains/bridge/abi.ts, and docs/BRIDGE.md
• Hyperlane recipient source: https://github.com/hyperlane-xyz/hyperlane-monorepo/blob/0063de628aeddfd5fecec6ca4719f7944223c1bd/solidity/contracts/test/TestRecipient.sol
• Hyperlane hook interface: https://github.com/hyperlane-xyz/hyperlane-monorepo/blob/0063de628aeddfd5fecec6ca4719f7944223c1bd/solidity/contracts/interfaces/hooks/IPostDispatchHook.sol
• Hyperlane quote implementation: https://github.com/hyperlane-xyz/hyperlane-monorepo/blob/0063de628aeddfd5fecec6ca4719f7944223c1bd/solidity/contracts/client/GasRouter.sol

Scope and duplicate check

No live bridge transfer was attempted, so delivery and relayer liveness remain unverified. A different bridged asset followed by a legitimate Hideki spot trade may still provide collateral. This report is about the documented USDso route's quote preflight and diagnostic hook mismatch.

On 2026-10-31, no equivalent report was found in the inspected public findings of PhiBao/dreamdex-perps-feedback (15), Bortlesboat/dreamdex-perps-feedback (2), DanhCaTuanNgoc/lucid-perps (15), or DreamCat's SDK feedback. That does not rule out private or unpublished reports.

November 1 reproduction on macOS

The USDso quote reverted with RPC code 3 and empty data at Shannon block 529372807. The STT, WBTC, WETH and HBTT quotes each returned zero. Reading the block again returned the same hash. Requests, responses and block hash