x402 payment check
Why a USDC transferWithAuthorization reverts: the signer, the token domain, the window and the seller's terms — and the domain a failing signature was really made for.
You paste: an X-PAYMENT header
Open the check →Paste it. Get a diagnosis.
Four checks for people who build with x402 payments and MCP servers. Free here: no account, no wallet. AI agents buy the very same answers over x402 for a fraction of a cent — this page opens what they pay for to people.
MCP rug-pull diff
Two tools/list results of one server — the one you approved and today's. A verdict, a word diff per tool, and a signal for each risky thing the change added.
You paste: two tools/list results
Open the check →MCP tool scan (WARDEN)
One tools/list. WARDEN, the open-source MCP firewall, checks every name, description, schema and annotation for prompt injection, exfiltration and credential theft.
You paste: a tools/list result
Open the check →MCP server history (HISTOR)
A server's address or registry name. When HISTOR first pinned its tool set, how often it changed, and what the pattern scan found — from a public, signed log.
You paste: a server address
Open the check →Deterministic, signed, the same for everyone
Deterministic
Same input, same answer. Rules and cryptography decide the verdict, not a model's mood.
Signed
The x402 and diff answers carry an Ed25519 signature of our HESTIA runtime; HISTOR signs its own.
Paid for by agents
The same checks are sold to AI agents over x402, USDC on Base. That is what keeps this page free.