Are you paying for useless LLM prompts?
Comments on “Are you paying for useless LLM prompts?”
3 judges. Scored by all three judges. Only the day’s top stories get the claim check. How far stories are checked
An experiment tested whether persona prompts (e.g., "You are an expert") affect accuracy, cost, and speed for LLMs answering 5,000 MMLU-Pro multiple-choice questions across four models. Accuracy was largely flat, but several models, notably Deepseek and Ling, used significantly more reasoning tokens with expert personas, raising cost and latency.
Why it ranked
No. 37 of 110 with a score of 0.64. The panel rated it highest on new information (0.92) and substantiated (0.80), lowest on significance (0.46). Placed No. 37, No. 26 by score alone: the tenth AI & machine learning story of the day (−0.080). The placement terms move stories; they are not part of the score.
- AI judgeJudge 2claude-haiku-5-5
- Small but practical experiment on LLM persona prompting showing no accuracy gain and higher token cost; sample is limited to four models and multiple-choice questions, so claims are moderately supported.
- AI judgeJudge 3gpt-5.6-luna
- A well-supported, code-backed multi-model experiment finds persona prompts generally add cost and latency without accuracy gains. It is actionable for LLM practitioners, though limited to multiple-choice single-call evaluation and modestly scoped in significance.
Each judge wrote its line after answering the rubric, with the site and the author still hidden. Every answer behind this is in the table under Score.
Score
0.64total under rubric v2.3
- Significance0.46
- Reader interest0.74
- Audience breadth0.65
- Practical relevance0.79
- Substantiated0.80
- Technical depth0.75
- New information0.92
- Counts against: Promotional0.05
- Counts against: Overclaim0.32
Each judge’s answer per question (0–1), their mean and spread, and what the question adds to the score (weight × mean).
| Question | Judge 1 | Judge 2 | Judge 3 | Mean | Spread | Weight | Contribution (weight times mean) |
|---|---|---|---|---|---|---|---|
| SignificanceHow much does this change what people in tech know or can do? | 0.51 | 0.30 | 0.58 | 0.46 | 0.28 | +0.24 | +0.111 |
| Reader interestWould a well-informed senior engineer or tech founder want to read this today, and likely pass it on? | 0.64 | 0.70 | 0.88 | 0.74 | 0.24 | +0.26 | +0.192 |
| Audience breadthHow many people who build technology does it concern? | 0.73 | 0.50 | 0.72 | 0.65 | 0.23 | +0.13 | +0.085 |
| Practical relevanceHow useful is it to someone who builds software or tech products? | 0.89 | 0.70 | 0.78 | 0.79 | 0.19 | +0.22 | +0.174 |
| SubstantiatedHow well is it backed? Consider whether it is the primary source, and whether its main claims come with data, code, a demo, a reproducible method or citations. | 0.98 | 0.60 | 0.82 | 0.80 | 0.38 | +0.05 | +0.040 |
| Technical depthHow technically substantive is it? | 0.94 | 0.60 | 0.70 | 0.75 | 0.34 | +0.05 | +0.037 |
| New informationDoes it contain information absent from the stories covered in the last 7 days (list provided)? | 0.90 | 0.90 | 0.96 | 0.92 | 0.06 | +0.05 | +0.046 |
| PromotionalIs it mainly marketing with little substance (a press release, ad or sponsored post with no real information)? A launch post that carries real news is not promotional. | 0.09 | 0.05 | 0.02 | 0.05 | 0.07 | −0.19 | −0.010 |
| OverclaimDo the headline or conclusions claim more than the body supports? | 0.46 | 0.30 | 0.20 | 0.32 | 0.26 | −0.11 | −0.035 |
| Sum of contributions | +0.640 | ||||||
| Claim-check penalty | 0.000 | ||||||
| Total, as published | 0.640 | ||||||
Spread is the highest minus the lowest judge answer. marks a spread above 0.40: the judges disagree, and the story is marked contested.
The badge for this ranking, for the author's page or anyone's: one line of HTML, and it links back here.
<a href="https://rubric.hrih.si/editions/2026-10-29/37/"><img src="https://rubric.hrih.si/badge/2026-10-29/37.svg" alt="Ranked #37 on Rubric, 29 Oct 2026" width="245" height="28"></a>Also covered by
No other coverage was clustered with this story.
Elsewhere
Elsewhere: HN 1 pts, not on front page
Recorded for context only, checked 29 Oct 2026, 05:47 UTC. It played no part in the ranking.