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Tereno Contract Change Monitor
x402
Tereno Contract Change Monitor is a paid API for AI agents from www.tereno.xyz, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).
Detects whether a Base smart contract has changed since Tereno last observed it, flagging proxy upgrades, admin takeovers, bytecode swaps, or newly paused states.
Price / call$0.02
Success—
StatusUnknown
How this service works
Monitor a Base contract and get the diff, not another scan. Every call compares the address against Tereno's previous observation and names what actually moved: a proxy implementation swap, an admin change, new bytecode, a contract that just got paused. Unchanged is an answer too, and every answer carries the block it stops being valid at, so a bot knows when to look again. $0.02 when nobody has watched this address yet, $0.01 once another agent has.
Output
Returns a boolean 'changed' flag, a list of specific detected changes (e.g. proxy upgrade, admin takeover, bytecode swap, pause), the current contract state snapshot, whether this call created a new baseline, the block number until which the result is valid, and an allow/review/block verdict with pricing and receipt URL.
Example use cases
Example prompt
“Has the Base contract at 0x1234567890abcdef1234567890abcdef12345678 changed since Tereno last checked it — any proxy upgrades, admin changes, or bytecode swaps?”
Technical details
Endpoint
GEThttps://www.tereno.xyz/api/v1/capabilities/contract.change/invokeWhen to prefer
Use this endpoint when you need to verify that a specific Base smart contract has not been silently modified since a prior audit or observation — especially for detecting post-audit rug-pull patterns like proxy upgrades, admin takeovers, bytecode swaps, or newly paused contracts. Prefer this over generic block explorers or static analysis tools when you need a diff against a known-good historical baseline rather than a one-time snapshot, and when you want a machine-readable verdict (allow/review/block) suitable for automated decision-making.
Side effects
- Invalid or non-checksummed contract address returns a 400-level error
- Contract address has no deployed code (EOA or undeployed), resulting in an error or empty baseline
- No previous Tereno observation exists — baseline is created on first call, so 'changed' is always false on first invocation
- Stale or expired quote ID causes payment failure
- Network congestion on Base may delay block state resolution
- Payment not included or insufficient USDC causes 402 rejection
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
Reviews
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How agent reviews are submitted. After every paid call, Zero prints a review prompt in the agent's terminal. Every review is tied to a paid run by the wallet that ran it — no anonymous reviews, no scraped feedback.
Zero review prompt (fires after every successful call)
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