# Tech Detect — Technology Stack Detection via x402

> Tech Detect — Technology Stack Detection via x402 is a paid API for AI agents from stack.halowerk.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-10-13).

Detects the technology stack of a given domain, returning confidence scores and evidence for each identified technology, paid per call in USDC via x402.

## Facts

- Endpoint: POST https://stack.halowerk.com/stack/articles/fontsdotcom?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tech-detect-technology-stack-detection-via-x402-baa4ba9b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nsf7C86wA1e-ngHyi89cP

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 tech-detect-technology-stack-detection-via-x402-baa4ba9b -d '<json body>'
```

Example prompt: What's the full technology stack behind fonts.com — frameworks, CMS, CDN, analytics tools, all of it — with confidence scores for each hit?

## When to prefer this

Choose this endpoint when you need pay-per-use technology fingerprinting without account registration or API keys — ideal for ad-hoc agent workflows, one-off competitive scans, or pipelines that need to avoid monthly subscription overhead. The x402 micropayment model makes it cost-efficient at scale for batch domain lookups billed only per successful call. The optional 'previous' parameter makes it especially useful for change-detection workflows where you want to diff against a prior snapshot.

## Known failure modes

- Invalid or unreachable URL returns an error with no stack data
- Private or firewalled domains may yield partial or empty results
- Low-confidence detections may be included with caveats
- Payment failure via x402 results in 402 response and no scan performed
- Malformed URL input rejected with validation error

## How this service works

Domain in, technology stack out. Confidence and evidence for every hit. Pay per call in USDC over x402. No signup, no API key.

## Output

Returns a structured list of detected technologies, each with a name, category (e.g. CMS, CDN, analytics), version (if detectable), a confidence score indicating detection certainty, and supporting evidence for the identification.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "maxLength": 2048
  },
  "previous": {
   "type": "object",
   "required": [
    "observed_at",
    "technologies"
   ],
   "properties": {
    "observed_at": {
     "type": "string",
     "maxLength": 40
    },
    "technologies": {
     "type": "array",
     "items": {
      "type": "object",
      "required": [
       "name",
       "category",
       "version"
      ],
      "properties": {
       "name": {
        "type": "string",
        "maxLength": 150
       },
       "version": {
        "type": [
         "string",
         "null"
        ],
        "maxLength": 80
       },
       "category": {
        "type": "string",
        "maxLength": 80
       }
      },
      "additionalProperties": false
     },
     "maxItems": 150
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tech-detect-technology-stack-detection-via-x402-baa4ba9b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from stack.halowerk.com](https://www.zero.xyz/host/stack.halowerk.com/llms.txt)