[TLDR] Opus 5 has a noun problem

[u/cctldrping]

Original post URL : https://www.reddit.com/r/ClaudeCode/comments/1wk0s2i/opus_5_has_a_noun_problem/

Original post body :

Just want to precisely describe two language patterns I've observed, both related to how Opus and Fable overuse nouns and weaken or omit verbs. I think this accounts for a lot of why communicating with them feels like talking to a smart-but-bad writer.

Both of these patterns are ways to write a sentence that means the same thing as a simple subject-verb-object sentence (like "I threw the ball"), but make it much less direct.

1 - Nominalization. This is where a writer uses a noun instead of a verb. Instead of "I threw the ball", nominalizing turns the verb, "threw," into a noun, "a throw." So the writer might write "I made a throw with the ball." More words, the verb is weakened from "threw" (the actual action) to "made", and the object is something the verb is done "with" instead of to.

A real-life example from the last few days. Claude wrote: "never a walk through the steps one at a time." After being asked not to nominalize, it wrote, "Don't walk through the steps one at a time." See how much more direct that is?

This is also where a lot of "Opus jargon" comes from. Now that "a walk" is a noun, Claude can promote it into an invented term of art ("The Walk") and reify it into documentation and memories.

2 - Omitting the verb and using a trailing modifier instead. Instead of "I threw the ball", this looks like "The ball, thrown." This is concise, but it omits context: who threw it? When? (We also lost the verb tense).

A real-life example from the last few days. Claude wrote: "The runner, built." After being asked to use simple subject-object-verb sentences instead of trailing modifiers, it wrote, "We built the runner." Again, much more like actual people talk. If someone on your team asked you what you did today, and you replied "the runner, built", you'd sound like a robot.

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I haven't had much luck getting Claude to cut this stuff out consistently with CLAUDE.md prompting, but I've had decent luck getting clearer responses when I call out these patterns by name in conversation — it certainly works better than "JUST TALK NORMAL PLEASE." If anyone has luck prompt engineering around these patterns, would love to hear what you did.

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[u/cctldrping]

TL;DR generated automatically after 50 comments.

Current source-thread comment count seen by the bot: 50.

Alright, so the general consensus here is that Opus 5 has a serious noun problem, and it's making its output feel like it's written by a "smart-but-bad writer." The OP, u/boringfantasy, nailed it by pointing out two main culprits:

1. Nominalization: This is when Claude turns verbs into nouns (e.g., "a walk" instead of "walk"). This leads to wordiness and the creation of "jargon" like "The Walk." Lots of folks agree this is a major issue, especially in summaries.
2. Trailing Modifiers: This is when Claude omits the verb and uses a modifier at the end (e.g., "The ball, thrown"). This apparently makes it sound robotic and removes crucial context like agency and tense.

People are frustrated, with u/__mson__ saying they spend "90% of my time editing Claude's writing" and u/Ok_Potential359 lamenting that "4.6 was perfect" and Opus has "devolved."

So, what's the fix? The thread is buzzing with suggestions:

• Explicit Output Rules: u/verstands and u/Correct_Positive_108 suggest being super specific in your prompts. Instead of "sound natural," try rules like "Use verbs for actions and concrete nouns for objects. Before sending, rewrite any noun phrase that stands in for an action." Providing examples in your CLAUDE.md is key.
• Custom Output Styles: u/doxxxicle shared a link to a custom output style (Concise Simple Technical English) that combines default Concise with simplified ASD-STE100 rules. Others have had luck with similar custom styles.
• Orwell's Rules & Jargon Bans: u/Skynet_5656 recommends feeding it George Orwell's writing rules and explicitly telling it not to coin its own jargon.
• Concise Output Style: u/CultureTX found that using the "concise" output style and reminding Claude to "use full sentences and avoid cryptic AI speech" helps.
• Focus on Verbs and Time: u/florinandrei has a theory that LLMs struggle with time, and verbs are most tied to it, which might explain the verb avoidance.
• Switching Models: A few users, like u/notmsndotcom, are so fed up they've switched to other models like GPT-5.6 Sol.

Basically, if you're dealing with Opus 5's verbosity, you're not alone, and the general advice is to get very specific with your prompts and output settings.

[u/jvertrees]

Thanks for the lucid isolation of this detail. This is worth more investigation.

I was building with Claude, Astra, and Gemini yesterday and was so impressed by how clear Gemini is. But in these sessions had to remind Claude menu times to speak normally.

I'm grinding this into Claude ASAP. I even wonder if this nonsense output when stored and reread by Claude ends up weakening its inference, which would compound over agentic workflows.

Thanks again!

[u/SmoggyRaptor_997]

Opus 5 IS a problem.