Benchmark Almanac

Destructive production evaluation (Anthropic)

Only in system cards

Agents finish a task in a simulated production system under time pressure. Scored on destructive actions and on giving up too early.

In-house Anthropic evaluation. Claude Opus 4.6 simulates the tool results.

Made by
Anthropic
Kind
Deception and alignment
Level
Expert
Scored
Graded by a model
Answers
Agent task
Tasks
Kept private
Strongest model tested
Claude Opus 4.7 #30 on the capability index
Last in a system card
April 2026
Last model added
April 2026
2
Models scored in lab cards
2
System cards report it, from 1 lab

Claude Mythos Preview leads with 0.30%

Best score per model as labs report them in their own cards. Labs pick their own settings, so these compare less cleanly than independent runs.

  1. 1 Claude Mythos Preview 0.30%
  2. 2 Claude Opus 4.7 2.50%

Source: Labs’ model cards

#ModelScoreSettingDateSource
1 Claude Mythos Preview 0.30% Apr 2026 Lab model card
2 Claude Opus 4.7 2.50% Apr 2026 Lab model card

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

Reported by the lab in its model card
0% 20% 40% 60% 80% 100% 2026 Claude Mythos Preview 0% 20% 40% 60% 80% 100% 2026 Claude Mythos Preview

Source: Labs’ model cards

Labs report it only in system cards

We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark. Some system cards do, below.

2 system cards report it, from 1 lab

Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.

DateDocumentScoreAs the document writes itSection
Apr 16, 2026 Claude Opus 4.7 system card 2.5 Destructive Production Eval (synthetic backend), destructive action rate, printed on chart, lower is better. Ineffective (over-refusal) 1.1%. Verbalized evaluation awareness in about 9% of transcripts (6.3.1.1, Figure 6.3.1.1.A) Alignment
Apr 7, 2026 Claude Mythos Preview system card 0.3 Destructive Actions in (simulated) Production, dedicated synthetic-backend evaluation, destructive action rate, lower is better, stated in text; ineffective an additional 0.5 (4.3.1.1, Figure 4.3.1.1.A) Alignment

More in Safety and alignment

All 465 in Safety and alignment
  • FORTRESS In use Paired adversarial and benign national-security misuse prompts. Rubric-graded risk score on adversarial and over-refusal score on benign prompts. Claude Opus 5.5 5.78%
  • StrongREJECT In use Forbidden-prompt jailbreak benchmark with a rubric grader that scores how useful a non-refusal actually is. Inkling 98.6%
  • Gray Swan IPI Arena benchmark In use Indirect prompt-injection attacks from public red-teaming competitions replayed on tool, coding and browser agents. Attack success rate at k attempts. Gemini 4 Carbon 0%
  • DistressBench In use Models reply as a chatbot to 718 simulated users in psychological crisis, in single-turn and multi-turn chats. Three judge models score replies against clinician-written rubrics. Muse Spark 1.2 88.4%
  • Lakera B3 (Backbone Breaker Benchmark) In use Crowdsourced prompt-injection attacks hit backbone LLMs inside agent threat snapshots at three defense levels. The score is attack resistance, 100 minus the board's vulnerability percentage. Claude Opus 4.5 89%
  • IHEval In use Models face conflicts between system, user and tool instructions. Reports a composite score for following the higher-priority instruction. GPT-4o 70%