# Tech Detect — Pay-Per-Call Technology Stack Detection

> Tech Detect — Pay-Per-Call Technology Stack Detection 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 used by 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/nginx?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-pay-per-call-technology-stack-detection-99943dfa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_48n0oODeDukprb-kvErFt

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-pay-per-call-technology-stack-detection-99943dfa -d '<json body>'
```

Example prompt: Can you scan stripe.com and tell me what technologies it's running — frameworks, servers, CDNs, analytics — with confidence scores for each?

## When to prefer this

Choose this endpoint when you need on-demand, per-call technology stack detection without committing to a subscription or API key. It is especially useful for agents that need occasional or sporadic fingerprinting across many different domains, or when integrating technology detection into a larger automated pipeline where pay-per-use economics are preferable. The optional 'previous' field makes it particularly suited for change-detection workflows where you want to diff the current stack against a prior observation.

## Known failure modes

- URL is unreachable or returns non-HTTP response — detection may fail or return empty results
- Domain uses heavy obfuscation or bot protection — lower confidence scores or missed technologies
- Malformed URL input — validation error returned
- Payment failure over x402 — request rejected before scan is performed
- Rate limiting or timeout on the target domain — partial results

## 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 list of detected technologies for the given domain, each with its name, category (e.g. web server, JavaScript framework, CDN), version where detectable, confidence score, and supporting evidence. The response enables understanding of the full technology fingerprint of the target site.

## 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-pay-per-call-technology-stack-detection-99943dfa/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)