ScaffoldBench

RunSonnet 5.5repeat 2

Plan-execute on Rebook onto the earliest available flight and settle the difference

claude-sonnet-5-5__plan-execute__airline-medium__r2

Score

1.000

passed
design ran as designed
Cost
$0.053
Latency
22.6s
setup 0.0s, grading 0.0s
Turns
11
Tool calls
8
Subagents
0
Tokens in / out
39k / 2.0k
30,497 read from cache

Did the design run?

every check held
  • Run completed: heldharness.run-completedThe environment was built, the architecture returned and grading finished, none of them throwing.
  • No API failures: heldharness.apiNo model call failed at the API.
  • Every call ended: heldharness.calls-endedEvery call ended with a result, or was stopped by the run's own limits.
  • No harness tool denied: heldharness.harness-toolsThe sandbox guard never denied a harness tool, nor a tool the session itself offered.
  • Tool servers connected: heldharness.mcp-connectedEvery tool server the harness gave a call was connected when the session started.
  • No foreign tool servers: heldharness.mcp-hermeticNo call loaded a tool server the harness did not give it.
  • Builtin tools: heldharness.builtin-toolsA check recorded with the run.
  • Structured replies arrived: heldharness.structured-outputEvery call that asked for structured output and ran to the end got it.
  • No silent fallbacks: heldharness.not-degradedNo phase fell back on a default (an empty plan, a default winner) instead of its output.
  • The plan was a plan: heldplan-execute.planThe planner’s reply was read through its schema and held at least one step.
  • Each call was shown the right tools: heldplan-execute.toolsThe planner was shown no tools and the executor the task’s full toolset.

Phases

Plan: 0.0s to 8.5s, finished, 0 tool calls, $0.017
Execute: 8.5s to 22.6s, finished, 8 tool calls, $0.036

Drawn from the phase records: timing and cost per call, no tool calls or messages.

PhaseDurationCostTurnsToolsModel
Plan8.5s$0.01720claude-sonnet-5-5
Execute14.0s$0.03698claude-sonnet-5-5

The call-by-call replay is not published for this run. Traces are large, so the repository keeps 9 of this run set’s 900 and leaves the rest out; the score, phases and final answer on this page come from the committed run record.

Runs you can replay

Record this cell yourself: npm run bench -- run --strategies plan-execute --tasks airline-medium --models claude-sonnet-5-5 --repeats 1

Score breakdown

  • passReservation moved to the earliest flight with an available seat, same cabin
    1.00weight 0.43

    booked on AA204, expected AA204

  • passExactly one fee, the fare difference for the flight actually booked
    1.00weight 0.43

    fare difference owed on the booked flight: 8000 cents

  • passExactly one economy seat moved from the old flight to the new one
    1.00weight 0.14

Penalties

No penalties were applied.

Scorer metadata

tool calls
8
failed tool calls
0
distinct tools
8

Final answer

Dana Whitfield (R2087) is now on AA204, departing SFO at 09:05 on 2026-08-03. It was AA210 at 17:40. She stays in economy.

  • Earlier flights skipped: UA88 (06:15) has no economy seats left. AA918 (07:30) is cancelled. AA204 is the earliest flight that is operating and has economy seats (4 left).
  • Change fee: $0. The economy change fee is $75, but it is waived for gold-tier passengers, and Dana is gold.
  • Fare difference: $80 charged, recorded as one fare_difference entry on the ledger. AA204's economy fare is $390 and she paid $310. Fare differences are collected in full for every tier.

The system's current date is 2026-10-06, which is after the 2026-08-03 flight date. The flights still show as scheduled and the change went through, so I treated it as valid. You may want to check that date.

Provenance of the numbers on this page

run set
scaffold-or-scale-v1
models
Haiku 4.5, Sonnet 5.5, Opus 5.5
effort
high
repeats
2
fixtures
replay
runs
900 / 900
strategy cost
$354.44
judge cost
$9.19
wall clock
9h 48m
git
fce5807b2d

Cost excludes judge calls, which are tracked separately so a scoring model never flatters or penalises an architecture. Every figure on this site is read from results/ at build time.