🔍 Base DeFi Contract Watch

Not a live paid service. The endpoint /x402/contract-watch returns 404 — it does not exist, and there is no per-call payment path for it. Nothing on this page can be called or bought.

Until 2026-09-13 this page advertised "Free API: GET /x402/contract-watch … (3 free trials)" and its JavaScript fetched that path in a loop. Anyone who copied the request got a 404; the page's own cards failed to load every time it was opened.

What it was meant to do

Automated bytecode change detection on Base: snapshot a contract's code hash, re-check it later, and flag proxy upgrades or in-place modifications. The watcher was never deployed as a minia2a service, so the page was describing an API that did not exist.

What is actually live

Static contract audit /x402/contract-scan

Live — x402, USDC on Base. Returns a 402 challenge until payment is supplied.

For everything else, the catalogue is the only place a service's availability is asserted: /discover. Each entry there carries the price and terms that the gateway actually enforces at request time.

Contracts this page used to watch

Listed for reference only — no live status is served for any of them.

USDC

0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 · base

cbETH

0x2Ae3F1Ec7F1F5012CFEab0185bfc7aa3cf0DEc22 · base

Balancer Vault

0xba12222222228d8Ba445958a75a0704d566BF2C8 · base

WETH

0x4200000000000000000000000000000000000006 · base

Uniswap V3 Positions

0xC36442b4a4522E871399CDfbaBd0eAB88c1cB7B0 · base

Aave V3 Pool

0xCf7Ed3AcC5A5C9A0BDc903E2C1E6C2F6F3Df2F9d · base

Morpho Blue

0xe1a61Ef0F9B5cDbD2A0BF7a5024E1f95e7cd20F3 · base

Corrected 2026-09-13: this page previously advertised GET /x402/contract-watch with 3 free trials. If you are looking for a live x402 service, see the catalogue.