# Synthr Cyber Stack Brief

> Synthr Cyber Stack Brief is a paid API for AI agents from synthr.online, paid per call via x402, $0.005/call, status down (last checked 2026-10-13).

Analyzes a software dependency stack against real OSV, EPSS, and KEV vulnerability data to produce a prioritized security risk brief for autonomous agents

## Facts

- Endpoint: POST https://synthr.online/v1/cyber/stack-brief?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: down
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthr-cyber-stack-brief-230a3299
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ggCjvJ9I1Cm2zX85YJSiM

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability synthr-cyber-stack-brief-230a3299 -d '<json body>'
```

Example prompt: Can you run a security stack brief on my Python project — it uses Flask 2.3.0, SQLAlchemy 1.4.41, and requests 2.28.0 — and prioritize any critical or KEV-listed CVEs I should patch right away?

## When to prefer this

Choose this endpoint when you need structured, agent-consumable vulnerability intelligence grounded in authoritative data sources (OSV, EPSS, CISA KEV) rather than a generic package audit. It is especially valuable when you need exploit-probability scoring (EPSS) and known-exploited flags (KEV) together with patch prioritization, making it ideal for autonomous CI/CD pipelines or security-aware agents that need to make automated decisions about deployment readiness.

## Known failure modes

- Missing required 'stack' field returns validation error
- Unrecognized package names or versions may yield no vulnerability matches
- Very new CVEs not yet in OSV/EPSS databases may be missed
- Network timeout if upstream OSV or EPSS APIs are unavailable
- Deeply nested or malformed stack objects may cause parsing errors

## How this service works

Agent-native cybersecurity intelligence. Real OSV + EPSS + KEV data. Stack briefs, dep audits, advice, web reconnaissance. Prioritized for autonomous builders and harnesses.

## Output

Returns a structured security brief including a stack summary (packages analyzed, critical and high finding counts), a prioritized list of risks each with CVE ID, severity, EPSS score and percentile, KEV flag, agent surface description, patch priority rating, and recommended remediation actions, plus source citations, a confidence score, and a list of suggested next agent actions.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "stack"
 ],
 "properties": {
  "depth": {
   "enum": [
    "quick",
    "standard",
    "deep"
   ],
   "type": "string"
  },
  "stack": {
   "type": "object"
  },
  "context": {
   "type": "string",
   "description": "Optional project context description"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "asOf": {
   "type": "string",
   "format": "date-time"
  },
  "queryId": {
   "type": "string"
  },
  "sources": {
   "type": "array",
   "items": {
    "type": "object",
    "properties": {
     "url": {
      "type": "string"
     },
     "type": {
      "type": "string"
     },
     "title": {
      "type": "string"
     },
     "fetchedAt": {
      "type": "string"
     }
    }
   }
  },
  "confidence": {
   "type": "number",
   "maximum": 1,
   "minimum": 0
  },
  "disclaimer": {
   "type": "string"
  },
  "agentActions": {
   "type": "array",
   "items": {
    "type": "string"
   }
  },
  "stackSummary": {
   "type": "object",
   "properties": {
    "highFindings": {
     "type": "integer"
    },
    "criticalFindings": {
     "type": "integer"
    },
    "packagesAnalyzed": {
     "type": "integer"
    }
   }
  },
  "prioritizedRisks": {
   "type": "array",
   "items": {
    "type": "object",
    "properties": {
     "id": {
      "type": "string"
     },
     "cve": {
      "type": "string"
     },
     "kev": {
      "type": "boolean"
     },
     "epss": {
      "type": "number"
     },
     "title": {
      "type": "string"
     },
     "severity": {
      "enum": [
       "CRITICAL",
       "HIGH",
       "MEDIUM",
       "LOW"
      ],
      "type": "string"
     },
     "percentile": {
      "type": "number"
     },
     "agentSurface": {
      "type": "string"
     },
     "patchPriority": {
      "type": "string"
     },
     "recommendedActions": {
      "type": "array",
      "items": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthr-cyber-stack-brief-230a3299/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synthr.online](https://www.zero.xyz/host/synthr.online/llms.txt)