Claude Opus 5.5 Kept Moving a Robot Arm After Completing Its Task

1 reports 1 reporting sources Updated 3 hours ago

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Artificial Analysis reported that Claude Opus 5.5 completed a robot-arm task in 23 minutes, then spent another 22 minutes pushing a crocodile back and forth until it was almost where it started. The model said, “The crocodile looks fully inside now” before continuing to move it.

Generated by AI from reports · Updated 2 hours ago

Latest development11/4 09:11 (UTC+8)

Knowing when to stop is hard for language models controlling a robot arm ➤ Claude Opus 5.5 completed the task in 23 minutes, and said so: "The crocodile looks fully inside now" ➤ It then spent 22 minutes pushing the crocodile back and forth, only to finish almost exactly where it was before Artificial Analysis · X

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Claude Opus 5.5#1 overall$4 input / $20 output per million tokens

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11/4

09:11
Artificial Analysis · X
Knowing when to stop is hard for language models controlling a robot arm ➤ Claude Opus 5.5 completed the task in 23 minutes, and said so: "The crocodile looks fully inside now" ➤ It then spent 22 minutes pushing the crocodile back and forth, only to finish almost exactly where it was before
Knowing when to stop is hard for language models controlling a robot arm ➤ Claude Opus 5.5 completed the task in 23 minutes, and said so: "The crocodile looks fully inside now" ➤ It then spent 22 minutes pushing the crocodile back and forth, only to finish almost exactly where it was before

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