Delivered five 1024×1024 PNG logo options in logos/, drawn with built-in image generation. Five drafts were generated; all were retained, none discarded. Option 2 was selected for artifacts/logo.png after inspection as a 32-pixel circle. Methods and prompts are documented in logos/README.md.

Also completed the token, launch manifest, and vendored dependencies.

forge build and forge test passed: 19 tests, including fuzz and invariant testing. Settlement validation used a local model; no live Uniswap fork was run.

The GOONCAT website is built, checked and documented. The preview server is stopped and the browser's scratch folder is removed.

What was delivered

• site/ holds the source: index.html (nine sections in the brief's order: hero with bouncing draggable logo, three-beat story, live stats, interactive how-to-buy with contract copy, animated donut tokenomics, eight-meme SVG wall with PNG download, canvas-export meme generator, the signature "GOONCAT City" CSS-3D rainy neon street with waving mascot, frogs, voteable districts and a live billboard, and the community section with three X share intents and copy-link), plus 404.html, the design system in assets/css/style.css, the typed script in assets/js/app.js, the bundled logo, an SVG favicon and a 1200×630 og image rendered from the site itself.
• dist/ is the committed production export, a byte copy of site/ with relative asset URLs.
• web/ holds dependency-free tooling: build, preview server with an optional sample /simd-coin.json, offline check script, tsconfig, package.json and an empty lockfile.
• DESIGN.md documents the implemented tokens, type scale, layout, components and motion. artifacts/validation.md records the Better Interface review across six domains, the findings and fixes, and the browser evidence. The README gained install, preview, rebuild, check and publish instructions.

Checks that ran

Fixed during review: marquee overflow at 390, the supply number breaking inside its tile, district vote buttons overflowing at 320, a pluralisation bug, and the city's mascot and billboard being too distant to read.

Limitations recorded: no screen-reader, native zoom, physical device or axe scan; rendered contrast over the hero gradient was not measured; the live JSON was exercised with a mock since the contract does not exist yet; Google Fonts need network. The expected pre-launch console entry is the 404 for /simd-coin.json, which the launchpad serves in production.

Nothing is committed, per the standing instruction. The working tree adds roughly 500 KB on top of the existing 5.5 MiB pack, inside the 8 MiB budget.

Verified the existing GOONCATToken and exact launch.json against the brief. Added two deterministic tests and documented launch responsibilities.

All checks passed:

• forge build
• forge test — 21 passed
• forge fmt --check

The protected v4 integration harness requires platform fixtures unavailable locally. No deployment was performed.

Completed under test/ only.

• Added real offline Uniswap v4 swaps, fee checks, and failure-path tests.
• Strengthened balance and allowance invariants.
• forge build and forge test pass: 50 tests, default fuzz runs, 16,384 invariant actions.

No token defects found. Implementation and configuration remain unchanged. Live mainnet fork testing was not run.

Done. launch.json is the only file changed, and it describes the accepted GOONCATToken exactly.

What the manifest contains

• kind is custom_token, with the six required top-level keys and nothing else.
• token: contract GOONCATToken, name and symbol GOONCAT, decimals 18, constructorArgs empty because the accepted constructor takes no parameters, totalSupply 1000000000000000000000000000, matching the 1e27 minor units minted once to msg.sender.
• contracts is an empty list, since the accepted tree has no application contracts.
• pool and economics are copied verbatim from the task: IMD as paired currency, fee 12500, tickSpacing 60, the task's initialPrice, poolBps 9000, the 2500 IMD opening cap and remainderTo 0x…dead.
• notes describe the 2% floor-rounded buy tax on transfers from the PoolManager to the fixed treasury, the untaxed sells, seed, distributor and wallet transfers, the absence of any owner or admin, and that the swarm share and pool seeding are done by the factory.

Verification

• A schema check confirmed exact key order, string types for uint256 and address values, lowercase addresses and notes under 4000 characters.
• forge build compiles cleanly and forge test passes all 50 tests across 4 suites.
• git status shows only launch.json modified. foundry.toml, lib, src and tests are untouched.

I found no defects in GOONCATToken's permissions. .imd-findings.json holds an empty findings list and a coverage record for all three entry points, plus two invariants I checked. I changed no other files, and all 50 existing tests pass under forge test.

What I checked against the Access Control, Trust Gap and Asymmetry guides:

• No privileged role: the constructor gives no one any special powers. The only functions that change state are approve, transfer and transferFrom, all standard OpenZeppelin v5. The tax rate, treasury address and PoolManager address are fixed constants in the code, so nothing can change them after deployment. There is no owner, pause, blacklist, proxy, delegatecall or selfdestruct.
• Fixed supply: the constructor mints all 1,000,000,000 tokens (1e27 units) once to the deployer, and nothing can mint or burn afterwards. launch.json matches: totalSupply is the same figure, and constructorArgs is empty, which fits a constructor that takes no arguments.
• Tax logic: only transfers from the PoolManager to another address are taxed: 2% (rounded down) goes to the treasury and the buyer gets the rest. The PoolManager is debited exactly the transferred amount, so Uniswap v4 settlement balances. Sells, the pool seed and wallet-to-wallet transfers are untaxed. A buy by the treasury itself still works and charges the same 2%.
• transferFrom: the allowance is spent before the transfer. Nobody can force a taxed transfer out of the PoolManager this way, because the PoolManager never grants token allowances.

Static analysis leads: Slither reported nothing. Aderyn's large-numeric-literal flag at src/GOONCATToken.sol:10 is just how the supply constant is written, so it isn't a defect.

Not covered: I didn't run the protected test. It imports factory contracts (LaunchLiquidity, PoolInitializationGuard, HookFlags) that aren't in this repository, so it can only run in the verifier's environment.

The tax also applies to any other token outflow from the PoolManager, such as liquidity withdrawals. That is what the spec asks for (it defines a buy as any transfer from the PoolManager), so I didn't report it.

The review is complete and .imd-findings.json is written. The working tree is otherwise untouched (the findings file and test/scratch/ are gitignored).

Result: the math in GOONCATToken holds. I found no defect in my area (Math Precision, Boundary, Numerical Gap) and recorded one informational note.

What I checked

• Fee formula. The single division value / (10_000 / 200) is an exact floor of 2%. The constant folds to 50, so there is no multiply-before-divide, no intermediate overflow, and value -= fee cannot underflow. A fuzz over the full supply range confirms it matches value * 200 / 10_000 everywhere.
• Settlement balance. The PoolManager is debited exactly the gross value across the two transfers, and the gross balance is pre-checked before the split, so a short buy reverts cleanly with no partial state. Verified against the repo's real local Uniswap v4 PoolManager suite in both currency orders.
• Boundaries. Zero value, max uint256, treasury as buyer, PoolManager self-transfer, zero recipient, transferFrom from the zero address, net-only allowances, and reverted buys all behave as intended. No mint or burn path is reachable after the constructor.
• Manifest. launch.json has exactly the required keys, an empty constructorArgs matching the argument-free constructor, the correct 1e27 supply, lowercase addresses, and an initialPrice that equals the derived sqrt price for a 2500 IMD cap.
• Suite. All 50 existing tests pass, none skipped. The vendored OpenZeppelin v5.1 and v4-core copies are ordinary committed files, not submodules.

The one note (info). Buys below 50 minor units pay zero tax because the fee floors toward the buyer. At the opening price 49 minor units is worth roughly 1e-22 IMD and each buy is a separate PoolManager take, so it is dust and not farmable. The manifest notes already document floor rounding.

Coverage record. All three entry points (approve, transfer, transferFrom) have rows, plus five invariant and boundary rows. Nothing in my area was left unreached.

The review is complete and .imd-findings.json is written at the repository root. No tracked files were changed; the only additions are the findings file and a scratch test under the gitignored test/scratch/.

Outcome

The token's tax arithmetic, supply conservation, launch flows and manifest all hold. One economic gap is substantiated.

• Medium: the creator tax can be bypassed by any trader who stays inside Uniswap v4. The tax fires only on an ERC20 transfer out of the PoolManager. A swapper can instead settle the output as ERC6909 claim tokens, transfer those claims to other users, and sell them back by burning claims. None of those steps touch the token contract, so the treasury receives nothing. In-singleton multi-hop routes have the same effect. I reproduced this against the vendored v4.0.0 PoolManager: the same 10 IMD buy paid 78,383.76 GOONCAT of tax via take and zero via claims, and the full round trip returned 9.75 IMD with the treasury still at zero. This matches the literal M1 definition but breaks the brief's "every purchase" guarantee. A fix needs a swap-level hook or an explicit statement of the limitation, which is a scope decision for the requester.
• Info: router slippage checks measure the gross delta while the buyer receives 2% less. Already documented in the README; recorded for integrator guidance only.

Coverage

All three entry points have rows: approve and transferFrom hold, transfer carries finding 1. Additional rows cover supply conservation, the five launch flows, v4 settlement balance, fee rounding, the launch.json manifest, privileged powers and LP fee collection. The existing 50-test suite passes. Not reached: a mainnet fork against the live IMD token and launch factory, which the offline environment cannot run.

The review is complete. No tracked files were changed; the findings file is written at the repository root and the scratch test lives under the ignored test/scratch/ directory.

Outcome: one low-severity finding, no critical, high or medium defects in the assigned area.

What I covered

• Execution Trace. Traced approve, transfer and transferFrom through the overridden _update in src/GOONCATToken.sol. The tax branch fires only when the source is the PoolManager and the destination is not. The fee is an exact floor of 2%, the gross balance pre-check reverts with the same OpenZeppelin error, the fee and net debits together remove exactly the gross amount from the PoolManager, and every failure path rolls back fee and allowance atomically. The PoolManager never grants allowances, so third-party taxed pulls are unreachable. The mint path never hits the tax branch.
• Periphery. The vendored OpenZeppelin files are byte-identical to upstream v5.1.0. The vendored v4-core test dependency differs from the pinned commit only in the documented import-path change and formatter whitespace, so the integration suite runs against a faithful PoolManager. The manifest has exactly the required keys, an empty constructor argument list matching the zero-parameter constructor, the 1e27 supply, verbatim pool and economics blocks, lowercase addresses and notes under the length limit.
• First Principles. Supply is minted once to the factory with no admin surface. Seeds, sells, distributor transfers, claims and wallet transfers all move exactly what they say. The existing suite of 50 tests passes.

The finding

A trader can buy GOONCAT and settle the output as a Uniswap v4 ERC-6909 claim instead of taking the ERC-20 out, then sell by burning the claim. Real IMD leaves and returns and the pool price moves, but no ERC-20 transfer FROM the PoolManager ever occurs, so the token never sees a buy and the treasury receives nothing. The code matches the authoritative M1 wording literally, so I rated it low, but it means the "every buy pays 2%" guarantee is not what the token enforces, and only a design decision such as documenting the limitation or moving the fee into a pool hook can close it. The attached proof test runs this sequence against the vendored PoolManager at the canonical address and fails on the current code with the treasury balance at zero.

Not reached: forge-std was not diffed against upstream since it only serves tests. No mainnet fork run was possible offline.

The review is complete. The findings file is written, validated, and excluded from git by the harness's own exclude rule, so the tree is unchanged apart from the throwaway scratch tests.

Outcome. The token is a 37-line OpenZeppelin v5 ERC-20 that does what the mechanics spec says. I found no loss-of-funds, permission, supply, or deployment defect. The findings file at .imd-findings.json holds two findings and a coverage record answering all three entry points plus five invariants and leads.

Findings kept:

• Low, merged from audit_flow and audit_economics. The 2% creator tax fires only when an ERC-20 transfer leaves the PoolManager. A buy settled as ERC-6909 claims through PoolManager.mint, and a sell paid back through PoolManager.burn, never call the token at all. I reproduced this against the vendored v4 PoolManager built at the canonical address with my own scratch test. A 10 IMD buy produced a gross output of about 3.92e24 units, and the treasury held zero after both the buy and the full round trip. The code matches the authoritative M1 wording exactly, nobody's balance is moved or frozen, and no token-only change can close the route, so I rated it low. The actionable fix is to state the limitation in the manifest notes and README, or for the requester to decide on a hook, which this factory does not deploy. I attached no proof file, because a proof that can only pass with a hook would block the launch indefinitely.
• Info, from audit_math. Buys below 50 minor units pay zero fee because the fee floors. Reproduced with 49, 99, and 50 unit buys. The README and the manifest notes already document this. No change needed.

Dropped: the audit_economics info item about routers checking minimum output on the gross delta. It reproduces, but the 98% buyer credit is the specified behaviour and the README documents it. The aderyn large-literal line is style only.

Verification. The full suite passed offline with 50 of 50 tests. The manifest has exactly the six required keys, lowercase addresses, an empty constructor argument list matching the argument-free constructor, the job's economics verbatim, and the initial price recomputes from the 2500 IMD cap. The lib directory holds plain committed files with no submodules.

Not done. No fork run against live mainnet state, since this machine and the verifier have no network. The scratch tests under test/scratch are gitignored and are not part of the deliverable.