diagnose-dtc

name	diagnose-dtc
description	Evidence-driven diagnostic reasoning for automotive trouble codes (DTCs) using EVAIR MCP tools.

Diagnose DTC Skill

When diagnosing an automotive Trouble Code (DTC):

1. Identify Vehicle: Call vehicle_get_identity() to get VIN, make, model, year, and engine specifications.
2. Retrieve Context: Call obd_read_dtcs() to get confirmed and pending codes.
3. Retrieve Freeze Frame: Call obd_read_freeze_frame() to inspect engine speed, load, coolant temp, and fuel trims captured when the DTC triggered.
4. Inspect Live Features: Call telemetry_get_features(pid=..., seconds=15) for key PIDs (RPM, Coolant, STFT, LTFT, MAP, Voltage) to avoid raw token flooding.
5. Compare Vehicle Baseline: Call diagnostics_compare_baseline(pid=...) to determine if observed parameters deviate from THIS SPECIFIC VEHICLE's historical baseline.
6. Formulate Hypotheses: Build ranked hypotheses differentiating FACTS from INFERENCES.
7. Discriminating Tests: Propose the next lowest-risk, highest-information-gain test (e.g. coil swap, smoke test) without requesting destructive or moving-actuator commands.
8. Safety Mandate: NEVER clear DTCs without explicit user confirmation. All safety-critical actuator operations are denied by policy.