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Uniswap bounty judges (Best API track)

SBO3L → Uniswap Best API

Source: docs/submission/bounty-uniswap.md

SBO3L → Uniswap Best API

Audience: Uniswap bounty judges (Best API track). Length: ~500 words.

Hero claim

A swap executed via the Uniswap API today is opaque. SBO3L makes the audit trail cryptographic — same Uniswap API, every call gated, signed, and bound to a re-derivable policy decision.

Why this bounty

“Best API” rewards integrations that surface Uniswap’s strengths in a way that wouldn’t exist otherwise. Our argument: an autonomous agent making a swap should produce the same on-chain effect as a human-driven swap, plus a portable cryptographic proof of why that swap was authorised. Today the audit trail for an agent-driven swap is “whatever the agent code happened to write” — i.e. usually nothing verifiable. With SBO3L’s UniswapExecutor as a GuardedExecutor, every swap intent runs through a deterministic policy boundary before the swap is constructed; slippage, MEV-protection, token-allowlist, and value-cap are all expressed as policy rules — not as bot logic. The decision is signed; the audit row links that decision to the eventual on-chain tx_hash via the Passport capsule.

The Uniswap API surface we exercise is intentionally vanilla: QuoterV2 for quotes, Universal Router for swap construction, and the standard SwapRouter02 for direct swaps. No custom contracts, no v4 hooks competing for sponsor attention, no rewrites of Uniswap’s own primitives. Our value-add is the cryptographic envelope around the Uniswap call, not the call itself.

Technical depth

Sepolia QuoterV2 — live quote evidence

UniswapExecutor::live_from_env() calls QuoterV2 (0xEd1f6473345F45b75F8179591dd5bA1888cf2FB3) on Sepolia for every swap intent. The quote evidence (quote_source: uniswap-v3-quoter-sepolia-…, real sqrt_price_x96_after, freshness timestamp, route WETH → USDC 0x1c7D4B19…) is captured into the Passport capsule. Off-by-one or stale quotes → policy protocol.deny_quote_stale rejection.

Universal Router with per-step policy gates (T-5-2 ✅, PR #171)

Every Universal Router command (V3_SWAP_EXACT_IN, WRAP_ETH, PERMIT2_PERMIT, etc.) is gated by an independent policy decision before encoding into the calldata stream. Slippage, recipient allowlist, and value-cap rules apply per step rather than per-bundle — so a multi-hop swap can have different slippage tolerance per hop, and a recipient deny on hop 3 doesn’t already-spent hops 1 and 2.

Smart Wallet integration with per-call policy gates (T-5-3 ✅, PR #183)

The agent acts as the Smart Account owner. Each call inside a Smart Wallet batch carries its own SBO3L PolicyReceipt and audit-event linkage. The capsule contains the full per-call decision tree, not just the outer batch result. Tampering with one inner call’s live_evidence invalidates the strict-hash verifier output for the whole capsule.

MEV protection in policy (T-5-4 in flight, PR #179)

Policy rules express MEV-safety primitives directly: slippage_bps ≤ policy.max_slippage, priority_fee bounded, quote.freshness ≤ policy.max_quote_age, recipient in policy.allowed_recipients. The audit row records exactly which rule fired; an auditor can reconstruct the bounded swap path without trusting our daemon being online.

Live verification

  • Sepolia QuoterV2 live quote: cargo install sbo3l-cli --version 1.2.0 && SBO3L_UNISWAP_RPC_URL=… sbo3l passport run swap-aprp.json --executor uniswap --mode live --quote-only --out /tmp/capsule.json && sbo3l passport verify --strict --path /tmp/capsule.json → PASSED with quote evidence in capsule
  • Real Sepolia swap with tx_hash in capsule (T-5-5, gated on T-5-1 #165) — capsule’s execution.live_evidence.tx_hash is the canonical proof; Etherscan link will be captured into demo-scripts/artifacts/uniswap-real-swap-capsule.json (artifact dir is gitignored — file appears at run time after bash demo-scripts/sponsors/uniswap-real-swap.sh against funded wallet)
  • Examples: examples/uniswap-agent-{ts,py}/ (T-5-6, PR #166) — TS + Py demo
  • Same capsule re-verified in browser: drag into https://sbo3l-marketing.vercel.app/proof — WASM verifier runs offline checks; tampering with tx_hash → capsule.live_evidence_mismatch

The cryptographic envelope is what’s new. The Uniswap call inside it is intentionally identical to what a human-driven swap looks like. Auditors, regulators, and operators can re-derive what was authorised, by whom, against which policy — across days, across teams, across systems — without trusting any single party. That’s the difference between an agent-driven swap and an opaque swap. Same Uniswap API; cryptographic audit trail.