# Demandex Gauge

> Demandex Gauge is a paid API for AI agents from api.demandex.dev, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-15).

Gauges market demand strength for a product or query by scoring it against an opportunity corpus

## Facts

- Endpoint: POST https://api.demandex.dev/v1/gauge
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/demandex-gauge-a8ea96a8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_E-U-_JOI5EyUqn-TqKgtD

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 demandex-gauge-a8ea96a8 -d '<json body>'
```

Example prompt: Can you gauge how strong the market demand is for 'ergonomic standing desk converters' using Demandex? Scope it to the office-furniture category.

## When to prefer this

Use this endpoint when you need to quantitatively gauge how much market demand exists for a specific product concept, niche, or keyword before investing further. Prefer it over browsing trend sites when you need a structured, scored demand signal from a curated opportunity corpus, especially as a precursor to fetching full opportunity cards via sibling endpoints.

## Known failure modes

- Query string shorter than 3 or longer than 200 characters returns a validation error
- Invalid category slug returns an error or empty corpus match
- Payment not included or insufficient USDC causes a 402 Payment Required response
- Malformed request body (wrong bodyType or missing required fields) returns a 400 error
- Query too generic may return a low-confidence or zero demand score

## How this service works

Paid ($0.03 USDC via x402). POST { "query": "...", "category"?: "..." } to get a demand verdict for any physical-product query. Answers are cached 7 days by normalized query; on a cache miss Demandex matches the query against the mined corpus (signals and cards by keyword) and runs one LLM synthesis call. query must be 3..200 chars. Reads the JSON body first, falling back to ?query=. Verdict shape: { query, verdictScore (0-100), demandTemperature (cold|warm|hot), rationale, topEvidence[] (≤5, e…

## Output

Returns a demand gauge result containing a score or signal indicating how strong and active market demand is for the queried product or topic, benchmarked against Demandex's opportunity corpus.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "query": {
   "type": "string",
   "description": "The product/demand query to gauge (3..200 chars). Required."
  },
  "category": {
   "type": "string",
   "description": "Optional category slug to scope the corpus match."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "cache": "miss",
  "query": "sony xm5 replacement headband",
  "charged": true,
  "fetchedAt": "2026-07-18T11:45:00.000Z",
  "rationale": "Frequent owner complaints about the OEM headband cracking, with buyers actively hunting for aftermarket replacements.",
  "topEvidence": [
   {
    "quote": "My XM5 headband cracked after 8 months and Sony wants $90 for a repair — where can I just buy the band?",
    "upvotes": 214,
    "permalink": "https://reddit.com/r/headphones/comments/abc123"
   }
  ],
  "verdictScore": 84,
  "demandTemperature": "hot",
  "relatedOpportunities": [
   {
    "slug": "sony-wh1000xm5-replacement-headband",
    "score": 87.4
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/demandex-gauge-a8ea96a8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.demandex.dev](https://www.zero.xyz/host/api.demandex.dev/llms.txt)