Human-readable diagnostic trouble code description. Paired with the numeric code rather than replacing it: the code is stable and the description is vendor text, so an alerting rule keys on the code while a human reads the description.
vehicle.dtc_descriptionEach of these is a real tag as the device or controller emits it, taken from the Forge mapping corpus. This is the table that does not exist anywhere else — the reason cross-vendor telemetry is hard is visible in a single column.
| OEM / profile | Raw tag as the device emits it | Confidence |
|---|---|---|
| Caterpillar | SPN_1636 | 1.00 |
| Detroit Diesel | SPN_1636 | 1.00 |
| Freightliner | SPN_1636 | 1.00 |
| John Deere | SPN_1636 | 1.00 |
| Kenworth | SPN_1636 | 1.00 |
| Mack Trucks | SPN_1636 | 1.00 |
| Navistar / International | SPN_1636 | 1.00 |
| PACCAR | SPN_1636 | 1.00 |
| Peterbilt | SPN_1636 | 1.00 |
| Volvo Trucks | SPN_1636 | 1.00 |
Every row above is an exact match — a deterministic pack entry or a confirmed corpus mapping — so all of them carry confidence 1.00. That is not a rounding: these are the two exact-match layers, and a tag that resolves here never reaches the embedding or LLM layers. Mappings resolved by the LLM layer do carry sub-1.0 confidence, but those are per-tenant and are not published here.
The canonical field is not just a name. It is a contract about units, sign convention and plausible range, enforced on the way in and re-checked at read time.
| SI / canonical unit | unitless (identifier or enumeration) |
| Measurement type | instantaneous |
| Distinct source tags in the corpus | 5 |
No mapping table to maintain, and no per-vendor branch in your code. The same request shape works for every OEM in the table above.
Read alongside this one.
vehicle.engine.oil_pressure vehicle.engine.oil_temp vehicle.turbocharger.rpm spindle_speed_rpm spindle_load_pct