How a rebuilt harness earns its numbers
This deck isn't about posting a number — it's about earning one. When infrastructure flakiness can masquerade as an agent failing, the score stops meaning anything.
So the first question is simple: is this a real contest at all?
Every comparison task lists the same four agent IDs — this is an apples-to-apples run, not a self-report.
And the workload behind those runs is concrete.
amplifier run --bundle foundation23 business and office-document tasks run 7 times each, plus 28 scored tasks — all judged on a 0-100 scale where a perfect score is 100.
Which is exactly where the catch hides.
A Docker issue, an API timeout, or a network error can be indistinguishable from a real agent mistake — and quietly poison the score.
So at v0.0.32 the team did something drastic about it.
At v0.0.32 (PR #45, David Koleczek, Feb 3 2026) the old Harness and ComparisonHarness were removed and benchmarking was rebuilt on a DAG job runner with parallel execution.
That runner does one crucial new thing with every failure.
The analysis runner classifies each failure — not lumping them together — so the harness can tell an agent's mistake apart from the environment's.
And that distinction drives the one rule that makes the score honest.
valid_trial is set to false only for INFRASTRUCTURE_ERROR. Infra noise never lands on an agent's score — so the number you read is the number the agent earned.
And that rule isn't a convention — it's baked into the data.
valid_trial and failure_category are first-class fields in the benchmark result schema. Credibility is engineered into the data model, so trustworthiness ships with every result.
The durable pattern: don't assert trust — build it into the record.
Data as of: February 2026. All metrics independently re-derived from command output in a fresh isolated session.
Feature status: microsoft/eval-recipes (MIT, "very early"), benchmarking rewritten at v0.0.32 (2026-02-03); latest verified tag v0.0.36 (2026-02-10). DavidKoleczek/amplifier-app-benchmarks v0.1.0 pins eval-recipes@v0.0.34.
Commands run:
gh api repos/microsoft/eval-recipes/tags --jq '.[].name' — tags v0.0.32–v0.0.36 existgh pr view 45 --repo microsoft/eval-recipes --json title,author,mergedAt,additions,deletions,changedFiles — +8224/−6925, 188 files, David Koleczek, merged 2026-02-03gh release view v0.0.32 --repo microsoft/eval-recipes — complete rewrite; Harness/ComparisonHarness removedgh api .../job_framework/runner.py?ref=v0.0.36 — "Job runner with DAG resolution and parallel execution"gh api .../evaluation/analysis_runner.py?ref=v0.0.36 — AGENT_ERROR / INFRASTRUCTURE_ERROR / TEST_ISSUE; VALID_TRIAL false only for infrastructuregh api .../schemas.py?ref=v0.0.36 — valid_trial, failure_category, score 0–100cat data/benchmarks/full.yaml — agent_ids [claude_code, gh_cli, amplifier_foundation, openai_codex]; comparison_runs: 7grep -c 'task_name:' full.yaml — 23 comparison tasks; ls data/tasks/full_benchmark | wc -l — 28 score tasksPrimary contributor: David Koleczek (DavidKoleczek) — top contributor to microsoft/eval-recipes and author of the benchmarking rewrite (PR #45) and amplifier-app-benchmarks.
Gaps: No results artifact (win rankings, per-task scores, or aggregate percentages) was found in the accessible repos; this deck therefore makes no claim about who won or by how much — only about how the harness earns a trustworthy number.