CHARM API

Verified OEM automotive data via REST API. All data sourced from factory service manuals, 1982–2013.

Authentication

All /api/v1/lookup requests require an API key passed in the X-API-Key header.

Rate limit: 50 requests per day per API key.

POST /api/v1/register

Request

curl -X POST https://chatwithcharm.com/api/v1/register \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]"}'

Response

{
  "api_key": "charm_a1b2c3d4e5..."
}

POST /api/v1/lookup

Query the OEM database. Returns structured part numbers, torque specs, and procedures.

Request body

query (required) — what you want to know
year — 4-digit year, 1982–2013
make — manufacturer (see /api/v1/vehicles)
model — model name
system — vehicle system (e.g. "brakes", "engine")
format — "full" (default, includes LLM synthesis) or "structured" (fast, regex extraction only)

If year, make, and model are provided, the query skips LLM parsing and goes straight to search. If only query is provided, an LLM parses out the vehicle info automatically.

Example — structured (fast, ~100ms)

curl -X POST https://chatwithcharm.com/api/v1/lookup \
  -H "Content-Type: application/json" \
  -H "X-API-Key: charm_YOUR_KEY" \
  -d '{
    "year": "2009",
    "make": "ford",
    "model": "taurus x",
    "query": "brake caliper part number",
    "format": "structured"
  }'

Example — full (with LLM synthesis, ~15s)

curl -X POST https://chatwithcharm.com/api/v1/lookup \
  -H "Content-Type: application/json" \
  -H "X-API-Key: charm_YOUR_KEY" \
  -d '{
    "query": "2005 Chevy Silverado spark plug gap and torque",
    "format": "full"
  }'

Response

{
  "vehicle": {"year": "2009", "make": "Ford", "model": "taurus x", "engine": "V6-3.5L"},
  "query": "brake caliper part number",
  "format": "structured",
  "synthesis_used": false,
  "confidence": "high",
  "results": {
    "part_numbers": [
      {
        "number": "5F9Z2B120BA",
        "component": "Front Right caliper",
        "source": "/Ford/2009/...",
        "purchase_options": [
          {"supplier": "BuyAutoParts", "url": "https://www.buyautoparts.com/...", "affiliate": true, "estimated_price": null},
          {"supplier": "AutoBarn", "url": "https://www.autobarn.net/...", "affiliate": true, "estimated_price": null},
          {"supplier": "RockAuto", "url": "https://www.rockauto.com/...", "affiliate": false, "estimated_price": null}
        ]
      }
    ],
    "torque_specs": [
      {"component": "Anchor plate bolts", "value": "150 Nm", "source": "..."}
    ],
    "fluid_capacities": [],
    "procedures": []
  },
  "sources": ["/Ford/2009/Taurus X AWD V6-3.5L/..."],
  "fallback": null,
  "affiliate_links": [],
  "meta": {
    "response_time_ms": 105,
    "search_time_ms": 104,
    "synthesis_time_ms": 0,
    "search_score_top": 0.795,
    "result_count": 10
  }
}

Confidence levels: high (score ≥ 0.6), medium (score ≥ 0.45), low (score < 0.45). Based on vector similarity of top search result.

GET /api/v1/vehicles

List all available makes. No authentication required.

curl https://chatwithcharm.com/api/v1/vehicles

Response

{
  "makes": ["Acura", "Acura Truck", "Audi", "BMW", ...]
}