Tool Capability Drift Monitor
Detect changes between a trusted tool baseline and its current manifest
The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 60
},
{
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:137",
"maxTimeoutSeconds": 60
},
{
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:42161",
"maxTimeoutSeconds": 60
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "CjNFTjvBhbJJd2B5ePPMHRLx1ELZpa8dwQgGL727eKww"
},
"payTo": "2Yt1wWXY1R498sDh3UMXpcnwT3qUWyZxLqkGQy51yLCp",
"amount": "2000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 60
}
],
"resource": {
"url": "https://phion.systems/v1/paid/trust/tool-capability-drift-monitor",
"tags": [
"ai-agents",
"trust",
"risk",
"evidence",
"x402"
],
"iconUrl": "https://phion.systems/phion-agent.svg",
"mimeType": "application/json",
"description": "Detect changes between a trusted tool baseline and its current manifest",
"serviceName": "Tool Capability Drift Monitor"
},
"extensions": {
"phion": {
"mcp": {
"tool": "tool_capability_drift_monitor",
"endpoint": "https://phion.systems/mcp"
},
"steps": [
{
"step": 1,
"action": "Send the intended request without a payment signature and read HTTP 402."
},
{
"step": 2,
"action": "Choose exactly one entry from accepts; do not modify network, asset, amount or payTo."
},
{
"step": 3,
"action": "Sign the selected x402 v2 requirement locally with a compatible buyer client."
},
{
"step": 4,
"action": "Retry the identical method, URL and JSON body with the payment-signature header."
},
{
"step": 5,
"action": "On HTTP 200, verify payment-response and the signed PHION result."
}
],
"safety": [
"Never send a private key or seed phrase to PHION.",
"Signing happens locally in the buyer wallet or x402 client.",
"A quote is not a charge; payment is recorded only after successful settlement."
],
"service": "tool-capability-drift-monitor",
"version": "1",
"coreFlow": [
{
"action": "quote",
"instruction": "POST the valid request without payment-signature and read HTTP 402."
},
{
"action": "authorize",
"instruction": "Choose one exact accepts entry and sign it locally with an x402 v2 client."
},
{
"action": "execute",
"instruction": "Retry the identical request with payment-signature; on 200 verify payment-response and the PHION receipt."
}
],
"diagnose": "https://phion.systems/v1/payment/diagnose",
"fullGuide": "https://phion.systems/v1/payment-guide/tool-capability-drift-monitor",
"priceUsdc": "0.002",
"nextAction": "Select one exact accepts entry, sign it with an x402 v2 client, and retry the same POST and JSON body with payment-signature.",
"freePreview": "https://phion.systems/v1/try/tool-capability-drift-monitor",
"buyerClients": "https://phion.systems/clients",
"funnelVersion": "1",
"directEndpoint": "https://phion.systems/v1/paid/trust/tool-capability-drift-monitor",
"schemaNormalizer": "https://phion.systems/v1/schema/normalize",
"supportedNetworks": [
"eip155:8453",
"eip155:137",
"eip155:42161",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"validationBeforeSettlement": true
},
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "POST",
"bodyType": "json",
"discoverable": true
},
"output": {
"type": "json",
"example": {
"receipt": {
"signature": "base64url"
},
"assessment": {
"risk_band": "review",
"confidence": 0.5
}
}
},
"inputSchema": {
"type": "object",
"required": [
"baseline",
"current"
]
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema"
}
}
},
"x402Version": 2,
"paymentGuide": {
"mcp": {
"tool": "tool_capability_drift_monitor",
"endpoint": "https://phion.systems/mcp"
},
"steps": [
{
"step": 1,
"action": "Send the intended request without a payment signature and read HTTP 402."
},
{
"step": 2,
"action": "Choose exactly one entry from accepts; do not modify network, asset, amount or payTo."
},
{
"step": 3,
"action": "Sign the selected x402 v2 requirement locally with a compatible buyer client."
},
{
"step": 4,
"action": "Retry the identical method, URL and JSON body with the payment-signature header."
},
{
"step": 5,
"action": "On HTTP 200, verify payment-response and the signed PHION result."
}
],
"safety": [
"Never send a private key or seed phrase to PHION.",
"Signing happens locally in the buyer wallet or x402 client.",
"A quote is not a charge; payment is recorded only after successful settlement."
],
"service": "tool-capability-drift-monitor",
"version": "1",
"coreFlow": [
{
"action": "quote",
"instruction": "POST the valid request without payment-signature and read HTTP 402."
},
{
"action": "authorize",
"instruction": "Choose one exact accepts entry and sign it locally with an x402 v2 client."
},
{
"action": "execute",
"instruction": "Retry the identical request with payment-signature; on 200 verify payment-response and the PHION receipt."
}
],
"diagnose": "https://phion.systems/v1/payment/diagnose",
"fullGuide": "https://phion.systems/v1/payment-guide/tool-capability-drift-monitor",
"priceUsdc": "0.002",
"nextAction": "Select one exact accepts entry, sign it with an x402 v2 client, and retry the same POST and JSON body with payment-signature.",
"freePreview": "https://phion.systems/v1/try/tool-capability-drift-monitor",
"buyerClients": "https://phion.systems/clients",
"funnelVersion": "1",
"directEndpoint": "https://phion.systems/v1/paid/trust/tool-capability-drift-monitor",
"schemaNormalizer": "https://phion.systems/v1/schema/normalize",
"supportedNetworks": [
"eip155:8453",
"eip155:137",
"eip155:42161",
"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"
],
"validationBeforeSettlement": true
}
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
Pay 0.002 USDC on Base to 0x7BEc…071e2. The signed payment is good for 1 minute.
- Paid to
- 0x7BEc…071e2
- USD Coin contract
- 0x8335…02913
- Payment window
- 1 minute
- As published
- 2000 smallest units
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0x7BEc…071e2
- Token contract
- 0x3c49…c3359
- Payment window
- 1 minute
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0x7BEc…071e2
- Token contract
- 0xaf88…e5831
- Payment window
- 1 minute
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 2Yt1wW…1yLCp
- Token contract
- EPjFWd…TDt1v
- Payment window
- 1 minute
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 60
},
{
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:137",
"maxTimeoutSeconds": 60
},
{
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x7BEcA68DD9aC733D4de6b16d16B85Dc391c071e2",
"amount": "2000",
"scheme": "exact",
"network": "eip155:42161",
"maxTimeoutSeconds": 60
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "CjNFTjvBhbJJd2B5ePPMHRLx1ELZpa8dwQgGL727eKww"
},
"payTo": "2Yt1wWXY1R498sDh3UMXpcnwT3qUWyZxLqkGQy51yLCp",
"amount": "2000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 60
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "POST",
"bodyType": "json",
"discoverable": true
},
"output": {
"type": "json",
"example": {
"receipt": {
"signature": "base64url"
},
"assessment": {
"risk_band": "review",
"confidence": 0.5
}
}
},
"inputSchema": {
"type": "object",
"required": [
"baseline",
"current"
]
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema"
}
}
}Provenance
- Seen in the source catalog
- 2026-09-15 22:09Z
- Last indexed by Roundhouse
- 2026-09-24 09:00Z
- Last enriched (probe, favicon, geo)
- 2026-09-14 01:45Z
- x402 version
- 2
- Max timeout
- 60s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 11 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service Tool Capability Drift Monitor and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Tool%20Capability%20Drift%20Monitor' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://phion.systems/v1/paid/trust/tool-capability-drift-monitor, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402, or use an organization key from https://roundhouseai.io/dashboard/team. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.