Repaired the failed size check by pruning nonessential vendored artifacts: upstream PDFs/docs, generated JS, snapshots, upstream test suites, and unused solmate files. Kept the required vendored Solidity sources, v4-core PoolManager/test routers, forge-std sources, and the minimal solmate Owned dependency v4-core needs.

Checks now pass:

• forge build
• forge test — 7 passed
• forge fmt --check

Current deliverable source size is about 1.36 MiB for lib/, plus the hook/test/README files, so it is comfortably below the 8 MiB upload limit.

Wrote one high-severity finding to .imd-findings.json: router-based identity lets the same user reverse through another router and lets users block unrelated traders sharing a router.

Included concrete reproduction steps traced through the vendored code; no runtime reproduction was executed. Project files remain unchanged.

Reproduced both failures and changed the guard to transaction-origin identity. Added regression tests, documented smart-wallet/relayer limitations, and recorded the response in .imd-responses.json.

Offline build, all 10 tests, and formatting checks pass. Build/tests used Solidity 0.8.26 via --use because the default compiler cache is read-only.

Wrote .imd-findings.json with one substantiated high-severity finding.

Validation performed:

• forge test -vv passed for the delivered suite.
• Temporary reproduction test confirmed the remaining tx.origin contract-wallet bypass.
• jq . .imd-findings.json validated the JSON shape.

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I fixed the reported defect. The hook now guards two addresses per pool: the address that called the PoolManager (the wallet or router) and tx.origin. forge build, forge test (11 tests) and forge fmt --check all pass.

• The bug: the guard was keyed only by tx.origin, so one contract wallet driven from two different origins got two separate entries and could reverse direction in the same block.
• The fix: in src/NoRoundTripHook.sol, beforeSwap checks both addresses through a new _guard helper. A reversal by either one in the same pool and block reverts. tx.origin is still checked, so an EOA can't get around the guard by switching routers.
• Tests: I added test_contractWalletCannotReverseByChangingOrigin, which follows your reproduction. The wallet swaps as origin A, the reversal as origin B reverts, and same-direction and next-block swaps still succeed. I did not run this test against the old code to confirm it failed there.
• Trade-off: all users of one router now share that router's guard, so two users trading opposite ways in the same block through the same router will revert one of them. The hook only sees the address that called the PoolManager plus tx.origin, never the wallet behind a router like PoolSwapTest, so I couldn't avoid this. The old test asserting independent guards per origin is replaced by test_sharedRouterSharesGuardAcrossOrigins, and the README states the limitation.

The answer to the finding is in .imd-responses.json with verdict fixed.

Review complete. Wrote one reproducible high-severity finding to .imd-findings.json.

The same contract wallet can still reverse direction within one block by changing both the originating EOA and router. The exact Foundry reproduction passed, demonstrating the bypass.