# Anthropic says outdated prompting habits are slowing down Claude Opus 5.5

Source: [The Decoder](https://the-decoder.com/anthropic-says-outdated-prompting-habits-are-slowing-down-claude-opus-5-5/) · 2026-11-14 · AI
Page: https://themorning.dev/story/anthropic-says-outdated-prompting-habits-are-slowing-down-claude-opus-5-5-59895b456217a461
Kind: tutorial · Impact: medium

## In brief

- Anthropic made Claude Opus 5.5 the default model on all paid plans.
- Anthropic published a guide that replaces older prompting habits.
- The main takeaway is to drop "think hard" and start at Medium effort.

## Why it matters

Developers using Claude Opus 5.5 may get faster, better results by changing how they prompt and which effort level they start with.

## What to do

- Stop using "think hard" in prompts
- Start at Medium effort when using Claude Opus 5.5

## Versions

- Claude Opus 5.5

## Coverage

- [Anthropic says outdated prompting habits are slowing down Claude Opus 5.5](https://the-decoder.com/anthropic-says-outdated-prompting-habits-are-slowing-down-claude-opus-5-5/) — The Decoder, 2026-11-14

Tags: anthropic, claude, prompting, llm, ai-models

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Brief generated by AI (claude-haiku-5-5) from the reporting listed under Coverage. Headlines belong to their publishers. The Morning Dev – https://themorning.dev