payment-ready until 2026-08-20
Structured second-opinion critique of a claim, plan, or draft output for autonomous agent callers. Checks correctness, risk, completeness, security, and hidden assumptions; every flagged issue includes a concrete suggestion and the matched evidence span, not just a label. Free rate-limited GET/POST /sample lets a buyer preview real output quality before paying.
Pay from $0.02 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.
listed 2026-07-25 · no on-chain settlement recorded yet
ASSESSMENT
updated 59m agoEvidence-backed signals, not a single score. Click any chip for the proof. Measured values stay read-only; unknown is honest.
reliability 51%
- uptime 24h
- 42.9%
- uptime 7d
- 53.9%
- uptime 30d
- 51%
- uptime 90d
- 51%
- response p95
- 3048ms
- avg response
- 1581ms
- total checks
- 1,711
Measured on the unpaid 402 handshake, not the paid call. A service can 402 correctly and still fail after payment.
compliance A (14/14)
14 of 14 x402 conformance checks pass. Full checklist below.
price $0.02 (p57 in AI)
- price (min)
- $0.02
- category percentile (min)
- p57 in AI
- endpoints / prices
- 1 / 1
- model
- flat
- stability
- 0%
risk clean
No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.
- domain age
- 14d
- registrar
- Cloudflare, Inc.
- hosting
- custom
- domain created
- 2026-07-25
Identity facts, not a risk score.
traction $0.00 30d · 0 buyers
- volume 30d
- $0.00
- buyers 30d
- 0
- settlements 30d
- 0
- first settlement
- ---
- last settlement
- ---
- top buyer share
- -
- trend 7d vs 30d
- -
- networks
- eip155:8453
- volume all-time
- $0
- settlements all-time
- 0
- median settlement 30d
- -
- max settlement 30d
- -
- settled via
- -
Conservative undercount: only USDC settlements via facilitators we measure are counted. A measured floor, not an estimate.
Top buyer share is a concentration signal, not part of the ranking score.
CHANGES
2 events, detecting since 2026-07-24Payout, price, and schema changes detected on this service's x402 wire. A payout rotation at an unchanged price shows up here even when nothing else moves. Full feed at /changes.
changes price changed 17d ago (2 since 2026-07-24)
price changed · 17d ago
POST /critique · eip155:8453 · USDC: 190000 → 20000
price changed · 19d ago
POST /critique · eip155:8453 · USDC: 10000 → 190000
Amounts are on-wire atomic units in the named asset.
WHAT IT DOES
ai-derivedNo AI synthesis has been produced for this service yet.
ENDPOINTS
| METHOD | PATH | DESCRIPTION | PRICE | NETWORK | ASSET | 402 CHANNEL |
|---|---|---|---|---|---|---|
| POST | /critique | $0.02 | Base | USDC | header |
REQUEST / RESPONSE EXAMPLE
An unpaid request to POST /critique returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i -X POST 'https://secondopinionapi.com/critique'
// 402 response (captured by monitor) · 1 payload · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x0b9B8a32AD1E821af6E470A4De97ba7188A130a4",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://secondopinionapi.com/critique",
"tags": [
"critique",
"ai-agents",
"review"
],
"mimeType": "application/json",
"description": "Structured second-opinion critique of a claim, plan, or draft output.",
"serviceName": "Second Opinion"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"body": {
"lenses": [
"correctness",
"risk",
"completeness"
],
"content": "Our new auth flow is 100% secure and will never be breached.",
"context": "reviewing a security claim before publishing it"
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"engine": "heuristic-v2",
"issues": [
{
"lens": "correctness",
"note": "Absolute claim (100%, never) with no evidence or source anywhere in the text.",
"evidence": "Our new auth flow is 100% secure and will never…",
"question": "What evidence supports \"100%\"?",
"severity": "medium",
"suggestion": "Either soften to a bounded claim or attach the measurement / source that justifies it."
}
],
"summary": "1 issue(s) found (0 high, 1 medium, 0 low). Most severe — correctness: Absolute claim (100%, never) with no evidence or source anywhere in the text.",
"verdict": "flagged",
"questions": [
"What evidence supports \"100%\"?"
],
"confidence": 0.55,
"lenses_applied": [
"correctness",
"risk",
"completeness"
],
"severity_counts": {
"low": 0,
"high": 0,
"medium": 1
}
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"required": [
"content"
],
"properties": {
"lenses": {
"type": "array",
"items": {
"enum": [
"correctness",
"risk",
"completeness",
"security",
"assumptions"
],
"type": "string"
},
"description": "Which critique lenses to apply. Defaults to correctness, risk and completeness; security and assumptions are opt-in."
},
"content": {
"type": "string",
"description": "The claim, plan, or draft text to critique."
},
"context": {
"type": "string",
"description": "Optional context about what this content is for."
}
}
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"properties": {
"engine": {
"type": "string"
},
"issues": {
"type": "array",
"description": "Each issue has lens, severity (high/medium/low), note, suggestion, and optionally evidence and question."
},
"summary": {
"type": "string"
},
"verdict": {
"enum": [
"pass",
"flagged"
],
"type": "string"
},
"questions": {
"type": "array",
"description": "Specific things the caller should resolve first."
},
"confidence": {
"type": "number",
"description": "0-1 confidence that the content is safe to act on exactly as written."
},
"lenses_applied": {
"type": "array"
},
"severity_counts": {
"type": "object"
}
}
}
}
}
}
}
}
},
"x402Version": 2
}
] OVER TIME
All charts use the 30d selector; each series spans only the dates it has data for. Every series is also served as JSON at /api/v1/services/second-opinion/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted). The on-chain series roll up hourly, so the latest day can be up to about an hour behind; distinct buyers are counted per payout address, so a service that settles to more than one address is an upper bound.
checklist grew 11->14 on 2026-07-28; a step here is a metric change, not a regression
Measured site and economics pillars from the assessment history, so the latest value shown elsewhere on this page reads as a point on a trend rather than a permanent state.
COMPLIANCE
14/14 checks pass · grade Alast 402 captured 2026-07-27 · last up 2026-08-13
- 402 payload captured
- accepts[] array present
- payTo address recoverable
- payTo at accepts[0].payTo (conformant shape)
- payTo is a valid on-chain address
- atomic price declared
- atomic price in a sane range
- asset (token) address declared
- network resolves to CAIP-2
- payment scheme declared
- served over HTTPS
- declares the current x402 version (2)
- EIP-712 domain parameters present on every EVM entry
- x402 v2 envelope delivered in the payment-required header
SITE PILLARS
- homepage reachable
- openapi doc
- pricing page
- llms.txt
- robots.txt
- terms page
recent checks (18) live · click to expand
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