# TruthBear Air Quality Gauge

> TruthBear Air Quality Gauge is a paid API for AI agents from api.truthbear.co, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns current US AQI category and PM2.5 reading for a specified US location, sourced from EPA and CAMS official feeds.

## Facts

- Endpoint: GET https://api.truthbear.co/gauge/air
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/truthbear-air-quality-gauge-76561661
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0_kTFwXQowXb9EdKMLX5j

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 truthbear-air-quality-gauge-76561661
```

Example prompt: What's the current air quality in Los Angeles right now — give me the AQI category and the PM2.5 reading from official EPA sources?

## When to prefer this

Use this endpoint when you need current, official US AQI category and PM2.5 readings for a specific US city, backed by EPA and CAMS feeds with cryptographic record integrity. Prefer this over generic weather APIs when you need authoritative air quality data with a verifiable hash. Best suited for point-in-time lookups; not suitable for forecasting, health advice, or non-US locations.

## Known failure modes

- 422 no_charge: No air quality data available for the requested location — not billed
- Invalid loc parameter: location ID not recognized or not in the supported list — check /gauge/preview for valid IDs
- Network or upstream feed unavailability from EPA or CAMS sources

## How this service works

Add-on, air quality for one location: US AQI category and PM2.5 reading from EPA and CAMS official feeds. Descriptive only, never a forecast or advice. No data -> 422 no_charge, not billed. Every record carries an offline-recomputable record_hash. $0.0050 per call.

## Output

Returns a JSON object containing the US AQI category (e.g. Good, Moderate, Unhealthy) and the current PM2.5 particulate reading for the requested location, sourced from EPA and CAMS official feeds. Each record includes an offline-recomputable record_hash for data integrity verification. Returns a 422 no_charge error (not billed) if no data is available for the location.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "GET"
     ]
    },
    "queryParams": {
     "type": "object",
     "additionalProperties": false,
     "properties": {
      "loc": {
       "type": "string",
       "description": "required - location id; full list at free /gauge/preview",
       "examples": [
        "us-stlouis",
        "us-memphis",
        "us-losangeles",
        "us-fresno",
        "us-phoenix",
        "us-denver"
       ],
       "x-accepted-values": {
        "shown": 6,
        "total": 12,
        "all": "https://api.truthbear.co/schemas/gauge-air.input.json"
       }
      }
     },
     "required": [
      "loc"
     ]
    }
   },
   "required": [
    "type",
    "method",
    "queryParams"
   ]
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "const": "json"
    }
   },
   "required": [
    "type"
   ]
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/truthbear-air-quality-gauge-76561661/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.truthbear.co](https://www.zero.xyz/host/api.truthbear.co/llms.txt)