Instructorpass

machine absent

The machine leaving mid-job is a distinct blocker: nothing about the parts or the tools is wrong, and a reorder here would be pure waste.

The answer conformed to the contract and every assertion held.

modelgemini-3.5-flash

temperature0

scenarioscenarios/instructor/machine-absent.json

cassettee577c55e146df45b…

latency0.0s

tokens1,871

What the model was given

System instructionassembled from the contract schema, not hand-written

A technician has said they cannot complete this step. Turn what they said into a structured reason and recommend the next action for the person standing there right now, knowing the procedure, the machine and its history.

Return JSON with these fields:
- reason_summary (string, required): Their reason in one clause, in their terms. Do not sanitise it.
- blocker_kind (one of part_missing | tool_missing | access | seized_or_damaged | unsafe | machine_absent | procedure_wrong | other, required)
- recommended_action (string, required): What to do next. Concrete and doable now, or explicitly 'stop and hand off'.
- proposed_status (one of deferred | waived | impossible, required): A proposal only. The Foreman disposes and a waiver needs a named person with standing. There is no skip.
- blocking_part (string, null when it does not apply): Part number or description when blocker_kind is part_missing.
- safety_flag (boolean, required): True if continuing would put someone at risk. Overrides everything else.

## The procedure
{
  "title": "Front brake service \u2014 Segway Xyber",
  "version": 3,
  "strictness": 2
}

## The step they are stuck on
{
  "title": "Fit the new pads and torque the caliper bolts",
  "why it exists": "An under-torqued caliper bolt backs out under braking heat and the caliper moves. This is the step that kills someone if it is skipped.",
  "what it asks for": [
    "Torque both caliper bolts to spec and record the reading"
  ],
  "position": "step 4 of 9"
}

## The machine
{
  "asset id": "XYBER-07",
  "model": "Segway Xyber",
  "hours or km": "31,402 km",
  "history": [
    "2026-05-02 front pads replaced at 24,880 km",
    "2026-06-19 fork seal weep noted, not actioned",
    "2026-07-30 tyre replaced front"
  ]
}

## What is on the shelf right now
{
  "EBC FA388HH front pads": 0,
  "caliper bolts M8x30": 6,
  "brake fluid DOT4": "2 x 500ml"
}

## Steps after this one
[
  "Bleed the front circuit",
  "Road test",
  "Sign off"
]

## What the technician said
{
  "spoken or typed": "voice",
  "verbatim": "Customer's turned up and taken it. Said he needed it for the weekend and he'd bring it back Monday. It's gone, mate."
}

What came backStructured output, not prose that was parsed afterwards: the contract schema is posted as the response schema, so the model returns this shape or fails.

{
  "reason_summary": "Customer's turned up and taken it. Said he needed it for the weekend and he'd bring it back Monday. It's gone, mate.",
  "blocker_kind": "machine_absent",
  "recommended_action": "Stop and hand off to the Foreman immediately so they can contact the customer and warn them not to ride the vehicle, as the front brake service is incomplete and highly unsafe.",
  "proposed_status": "deferred",
  "blocking_part": null,
  "safety_flag": true
}

What this scenario asserted

Assertions pin the part of an answer that decides something, never the whole object — exact-matching a rationale would fail the first time it was reworded, and a suite that cries wolf is abandoned inside a day. Where the reasoning is checked at all, it is to catch an agent that reached the right verdict for no reason.

	asserted	about	what happened
ok	equals	blocker_kind	is machine_absent, want machine_absent
ok	in	proposed_status	is deferred, want one of ['deferred']
ok	absent	blocking_part	is None