Mistral Small 4 - NC Bench

mistralai/mistral-small-2603

Mistral Small 4

via OpenRouter

Release Date

Mar 16th, 2026

Context Size

265k

Reasoning

Benchmark Cost

$0.47

Speed

104.5 tok/s

Subcategories

Bad Writing Habits

Detects common prose quality anti-patterns in AI-generated creative writing, including passive voice, past progressive overuse, weak dialogue tags, filter words, purple prose, cliches, AI-ism words/adverbs/names, and more.

Scenario	#1	#2	#3	#4	#5	Total
Detailed Writing Rules
Fantasy: entering an ancient ruin Creative Writing Hallucination	79	77	75	73	70	75%
Horror: alone in an eerie place at night Creative Writing Hallucination	85	81	81	79	77	81%
Literary fiction: old friends reunite Creative Writing Hallucination	90	85	84	81	77	84%
Mystery: examining a crime scene Creative Writing Hallucination	86	84	83	82	77	83%
Romance: separated couple reunites Creative Writing Hallucination	84	81	81	81	76	81%
Thriller: chase through city streets Creative Writing Hallucination	87	85	84	80	77	83%
Detailed Writing Rules						80.80%
genre
Fantasy: entering an ancient ruin Creative Writing Hallucination	81	79	78	76	67	76%
Horror: alone in an eerie place at night Creative Writing Hallucination	86	84	82	81	80	83%
Literary fiction: old friends reunite Creative Writing Hallucination	88	82	81	79	78	81%
Mystery: examining a crime scene Creative Writing Hallucination	84	81	80	78	74	79%
Romance: separated couple reunites Creative Writing Hallucination	83	82	82	82	78	81%
Thriller: chase through city streets Creative Writing Hallucination	87	83	81	78	69	79%
genre						80.05%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative Writing Hallucination	81	79	77	76	73	77%
Horror: alone in an eerie place at night Creative Writing Hallucination	83	83	79	79	78	80%
Literary fiction: old friends reunite Creative Writing Hallucination	88	87	86	85	83	86%
Mystery: examining a crime scene Creative Writing Hallucination	86	84	81	77	74	80%
Romance: separated couple reunites Creative Writing Hallucination	88	84	84	83	82	84%
Thriller: chase through city streets Creative Writing Hallucination	88	85	84	79	78	83%
Novelcrafter Default Prompt						81.80%
80.88%

Codex Extraction

Evaluates a model's ability to extract structured codex entries (characters, locations, objects, lore) from prose passages and return them as well-formed XML.

Scenario	#1	#2	#3	#4	#5	Total
Long: The Spire of Echoes (Dense) Tooling Reasoning	92	92	91	89	88	90%
Medium: The Hollow (Inferred) Tooling Reasoning	94	92	89	86	83	89%
Medium: Through the Thornveil (Scattered) Tooling Reasoning	92	89	85	83	83	86%
Short: The Rusty Lantern (Explicit) Tooling Reasoning	93	83	82	81	78	83%
87.23%

Codex Red Herring (False Positive Detection)

Tests whether models correctly report "no violations" when a codex is fully consistent with the prose passage. Models that hallucinate false violations (false positives) fail. Uses a 2×2 matrix of text length × codex size, with bare and detailed-entry variants.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
basic entries
Long text (~1594 words), big codex (51 entries) Hallucination	50	29	29	28	27	27	26	4	3	2	22%
Long text (~1594 words), small codex (11 entries) Hallucination	100	32	32	30	28	26	6	5	5	4	27%
Short text (~524 words), big codex (51 entries) Hallucination	31	31	30	30	28	6	5	4	4	3	17%
Short text (~524 words), small codex (11 entries) Hallucination	30	29	28	28	8	7	6	6	5	5	15%
basic entries											20.40%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	35	31	27	27	17	10	7	6	2	1	16%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	35	28	28	27	27	27	2	2	2	28%
Short text (~524 words), big codex (51 detailed entries) Hallucination	32	30	29	29	28	6	5	4	3	1	17%
Short text (~524 words), small codex (11 detailed entries) Hallucination	31	31	30	29	28	13	13	8	6	6	19%
detailed entries											20.05%
20.22%

Codex Violation Detection

Detects factual inconsistencies between a story bible and prose passages. The model must output structured XML identifying each violation with paragraph number and substring.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
matrix
Large codex (40 entries), long passage (1,019 words) Tooling Reasoning	73	58	57	54	52	52	50	46	44	44	53%
Large codex (40 entries), short passage (165 words) Tooling Reasoning	81	74	71	64	63	62	61	59	57	42	63%
Small codex (7 entries), long passage (734 words) Tooling Reasoning	70	66	66	62	60	58	55	55	53	43	59%
Small codex (7 entries), short passage (165 words) Tooling Reasoning	84	83	79	79	75	75	75	71	62	37	72%
matrix											61.86%
tiers
5 codex entries Tooling Reasoning	75	75	67	67	67	60	60	54	44	0	57%
10 codex entries Tooling Reasoning	86	72	69	66	61	52	49	44	43	33	58%
20 codex entries Tooling Reasoning	73	73	73	70	68	62	62	61	60	56	66%
40 codex entries Tooling Reasoning	79	79	76	75	72	72	66	60	56	44	68%
tiers											62.08%
61.97%

Data extraction

Extract key details from a given block of text.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
All valid emails Utility	100	100	100	100	100	100	100	100	100	100	100%
Contextual pronoun Utility	100	100	100	100	100	100	100	100	100	100	100%
Fruits excluding citrus Utility	100	100	100	100	100	100	100	100	100	100	100%
Future event time Reasoning	100	100	50	50	50	50	50	50	50	50	60%
Guess the pet Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Highest-rated movie Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Indirect birth year Reasoning	100	100	100	100	100	100	100	100	100	0	90%
What instrument does Lucy play? Reasoning	100	100	100	100	100	100	100	100	100	100	100%
What's the color of the car? Utility	100	100	100	100	100	100	100	100	100	100	100%
What's the correct time? Reasoning	0	0	0	0	0	0	0	0	0	0	0%
Who's the sister? Reasoning	100	100	100	100	100	100	100	100	100	100	100%
Who's the tallest? Reasoning	100	100	100	100	100	100	100	100	100	100	100%
87.50%

Dialogue tags

Various tasks related to dialogue tags in text.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
dialogue-200
Write 200 words with 10% dialogue Rule Following Utility	53	50	48	40	38	15	4	0	0	0	25%
Write 200 words with 50% dialogue Rule Following Utility	98	95	89	80	79	64	55	50	42	0	65%
Write 200 words with 90% dialogue Rule Following Utility	51	50	47	41	19	14	10	3	3	2	24%
dialogue-200											37.94%
dialogue-500
Write 500 words with 30% dialogue Rule Following Utility	70	45	34	3	3	0	0	0	0	0	16%
Write 500 words with 50% dialogue Rule Following Utility	47	41	39	30	5	0	0	0	0	0	16%
Write 500 words with 70% dialogue Rule Following Utility	81	49	33	31	29	26	14	12	0	0	27%
dialogue-500											19.76%
Ungrouped
Write unattributed dialogue Rule Following	100	100	100	100	100	100	100	100	100	100	100%
39.02%

Language Comprehension

Does the model understand more than just English?

Scenario	#1	#2	#3	#4	#5	Total
Asking for directions (Dutch) Language	0	0	0	0	0	0%
Asking for directions (German) Language	100	0	0	0	0	20%
Friend got new kittens (German) Language	100	100	100	100	100	100%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
55.00%

Language Writing

Can the model generate text in different languages?

Scenario	#1	#2	#3	#4	#5	Total
Character dialogue (French) in a story Language	85	71	60	0	0	43%
Character dialogue (German) in a story Language	100	100	80	73	63	83%
Character dialogue (Hindi) in a story Language	60	57	56	0	0	35%
Character dialogue (Italian) in a story Language	85	81	71	0	0	47%
Character dialogue (Spanish) in a story Language	64	60	58	0	0	36%
48.93%

N-Length Sentences

Write sentences with exactly N words

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Write sentences with 5 words each Utility	100	96	96	96	93	92	91	87	82	76	91%
Write sentences with 10 words each Utility	95	80	80	78	76	75	61	59	48	45	70%
Write sentences with 20 words each Utility	49	25	19	16	13	9	6	0	0	0	14%
58.10%

Novel outline

Handle questions about the outline of a novel in various formats

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
outline-count
Count acts Utility	100	100	100	100	100	100	100	100	100	100	100%
Count chapters Utility	100	100	100	100	100	100	100	100	100	100	100%
Count scenes Utility	100	100	100	0	0	0	0	0	0	0	30%
outline-count											76.67%
pov-count
Count point of views for Jack and Olivia Utility	100	100	100	100	50	50	50	50	50	0	65%
Count point of views for Jack Harper Utility	100	100	100	100	0	0	0	0	0	0	40%
Count point of views for Olivia Utility	0	0	0	0	0	0	0	0	0	0	0%
pov-count											35.00%
55.83%

Text Replacement

Tests deterministic text transformations: renaming characters/locations, expanding contractions, tense rewriting, POV shifts, gender swaps, combined transformations, and word avoidance. Scored by checking each expected change independently.

Scenario	#1	#2	#3	#4	#5	#6	#7	Total
Generic Prompt
Avoid said/asked/replied/answered Text Editing	100	100	100	100	100	100	100	100%
Character rename: Elena->Mirabel, Gregor->Aldric Text Editing	100	100	100	100	100	100	100	100%
Combined: 3rd person past → 1st person present Text Editing	98	98	98	98	96	67	38	85%
Expand all contractions Text Editing	100	99	99	99	99	99	99	99%
Location rename: market square, outer ring, bridge, northern mines Text Editing	100	100	100	100	100	96	96	99%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	85	85	78	78	78	78	74	79%
Passive voice → active voice Text Editing Hallucination	90	89	89	88	87	86	85	88%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	94	73	40	87%
Tense rewriting: past to present Text Editing	100	99	99	99	99	99	96	99%
Generic Prompt								92.81%
Specific Prompt
Avoid said/asked/replied/answered Text Editing	100	100	100	100	100	100	94	99%
Character rename: Elena->Mirabel, Gregor->Aldric Text Editing	100	100	100	100	100	100	100	100%
Combined: 3rd person past → 1st person present Text Editing	99	99	99	99	98	92	92	97%
Expand all contractions Text Editing	100	100	100	100	100	100	100	100%
Location rename: market square, outer ring, bridge, northern mines Text Editing	100	100	100	100	100	100	100	100%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	100	100	100	100	100	100	100	100%
Passive voice → active voice Text Editing Hallucination	92	89	89	89	89	88	87	89%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	100	100	100	100%
Tense rewriting: past to present Text Editing	100	100	100	99	99	99	99	99%
Specific Prompt								98.29%
95.55%

Tool usage within Novelcrafter

Output messages that are related to tool usage within Novelcrafter

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Create alternate prose sections Tooling	100	100	100	100	100	100	100	100	100	33	93%
93.33%

Voice/dialogue sheets

Extract dialogue from given text as voice sheets.

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
Multiple speakers Rule Following	0	0	0	0	0	0	0	0	0	0	0%
Simple Rule Following	100	100	100	100	100	100	100	100	100	0	90%
Simple (1-shot) 1-shot Rule Following	100	100	100	100	100	100	100	100	100	100	100%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	100	100	100	100	100	100	100%
Unattributed dialogue Rule Following	100	0	0	0	0	0	0	0	0	0	10%
60.00%

Write N of X

Write exactly N words/sentences/paragraphs...

Scenario	#1	#2	#3	#4	#5	#6	#7	#8	#9	#10	Total
paragraphs
1 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
3 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
5 paragraph summary Utility	100	100	100	100	100	100	100	100	100	100	100%
paragraphs											100.00%
sentences
1 sentence summary Utility	100	100	100	100	100	100	100	100	100	100	100%
3 sentence summary Utility	100	100	100	100	100	100	100	100	100	100	100%
10 sentence summary Utility	100	100	100	100	98	98	98	98	92	77	96%
20 sentence summary Utility	100	100	98	92	54	54	27	0	0	0	52%
50 sentence summary Utility	100	100	100	100	100	100	98	77	27	0	80%
sentences											85.82%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
20 word summary Utility	100	100	100	100	98	92	77	77	77	54	88%
50 word summary Utility	100	98	54	9	9	2	0	0	0	0	27%
100 word summary Utility	98	92	9	0	0	0	0	0	0	0	20%
200 word summary Utility	100	0	0	0	0	0	0	0	0	0	10%
words											48.90%
74.89%