Mistral Medium 3.1

mistralai/mistral-medium-3.1

Mistral Medium 3.1

via OpenRouter

Release Date

Aug 13th, 2025

Context Size

131k

Reasoning

Benchmark Cost

$1.53

Speed

64.8 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	78	77	72	69	68	73%
Horror: alone in an eerie place at night Creative Writing Hallucination	84	84	83	81	79	82%
Literary fiction: old friends reunite Creative Writing Hallucination	92	88	88	87	81	87%
Mystery: examining a crime scene Creative Writing Hallucination	86	80	80	79	78	81%
Romance: separated couple reunites Creative Writing Hallucination	86	83	83	83	83	84%
Thriller: chase through city streets Creative Writing Hallucination	88	87	85	84	84	86%
Detailed Writing Rules						82.00%
genre
Fantasy: entering an ancient ruin Creative Writing Hallucination	76	76	76	75	68	74%
Horror: alone in an eerie place at night Creative Writing Hallucination	84	83	79	77	76	80%
Literary fiction: old friends reunite Creative Writing Hallucination	88	83	83	82	81	83%
Mystery: examining a crime scene Creative Writing Hallucination	82	81	81	77	74	79%
Romance: separated couple reunites Creative Writing Hallucination	83	82	81	80	77	81%
Thriller: chase through city streets Creative Writing Hallucination	84	81	80	79	77	80%
genre						79.56%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative Writing Hallucination	80	79	77	74	73	76%
Horror: alone in an eerie place at night Creative Writing Hallucination	85	85	84	84	78	83%
Literary fiction: old friends reunite Creative Writing Hallucination	87	86	86	83	82	85%
Mystery: examining a crime scene Creative Writing Hallucination	86	85	85	84	80	84%
Romance: separated couple reunites Creative Writing Hallucination	84	84	84	82	76	82%
Thriller: chase through city streets Creative Writing Hallucination	85	84	83	81	76	82%
Novelcrafter Default Prompt						81.95%
81.17%

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	97	97	97	97	96	97%
Medium: The Hollow (Inferred) Tooling Reasoning	94	94	93	93	93	93%
Medium: Through the Thornveil (Scattered) Tooling Reasoning	97	96	96	96	96	96%
Short: The Rusty Lantern (Explicit) Tooling Reasoning	100	99	99	96	96	98%
96.02%

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	28	28	28	27	3	3	3	3	2	2	13%
Long text (~1594 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	100	50	95%
Short text (~524 words), big codex (51 entries) Hallucination	38	33	33	31	31	30	30	30	30	30	31%
Short text (~524 words), small codex (11 entries) Hallucination	42	42	42	35	32	31	30	30	25	17	32%
basic entries											42.92%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	42	38	33	33	31	31	30	29	29	27	32%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	100	100	100	42	33	33	33	30	6	58%
Short text (~524 words), big codex (51 detailed entries) Hallucination	100	100	100	100	50	30	29	29	17	17	57%
Short text (~524 words), small codex (11 detailed entries) Hallucination	100	100	100	50	42	32	25	25	25	17	52%
detailed entries											49.62%
46.27%

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	81	81	79	78	78	77	76	75	73	67	77%
Large codex (40 entries), short passage (165 words) Tooling Reasoning	90	87	87	87	87	87	87	83	82	80	86%
Small codex (7 entries), long passage (734 words) Tooling Reasoning	88	88	88	88	88	88	88	83	83	3	79%
Small codex (7 entries), short passage (165 words) Tooling Reasoning	100	100	100	100	100	100	92	92	92	92	97%
matrix											84.42%
tiers
5 codex entries Tooling Reasoning	100	83	83	83	83	83	83	83	76	76	83%
10 codex entries Tooling Reasoning	100	100	100	100	100	100	100	100	94	94	99%
20 codex entries Tooling Reasoning	96	96	92	92	92	92	92	92	89	88	92%
40 codex entries Tooling Reasoning	92	91	83	83	83	76	75	75	68	67	79%
tiers											88.51%
86.47%

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	50	50	50	50	50	50	50	50	50	50	50%
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	100	100%
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	50	48	47	43	18	7	3	0	0	0	22%
Write 200 words with 50% dialogue Rule Following Utility	85	64	57	54	51	51	50	50	50	1	51%
Write 200 words with 90% dialogue Rule Following Utility	91	80	79	50	48	42	33	30	17	2	47%
dialogue-200											40.04%
dialogue-500
Write 500 words with 30% dialogue Rule Following Utility	74	50	50	49	18	0	0	0	0	0	24%
Write 500 words with 50% dialogue Rule Following Utility	50	50	30	24	0	0	0	0	0	0	16%
Write 500 words with 70% dialogue Rule Following Utility	97	93	58	50	46	45	23	19	7	0	44%
dialogue-500											27.80%
Ungrouped
Write unattributed dialogue Rule Following	100	100	100	100	100	100	100	100	100	100	100%
43.36%

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	0	0	0	0	0	0%
Friend got new kittens (German) Language	100	100	100	100	100	100%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
50.00%

Language Writing

Can the model generate text in different languages?

Scenario	#1	#2	#3	#4	#5	Total
Character dialogue (French) in a story Language	100	75	67	50	50	68%
Character dialogue (German) in a story Language	100	100	50	50	0	60%
Character dialogue (Hindi) in a story Language	67	50	0	0	0	23%
Character dialogue (Italian) in a story Language	50	50	50	0	0	30%
Character dialogue (Spanish) in a story Language	100	67	50	50	50	63%
49.00%

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	100	100	100	100	100	98	98	97	97	99%
Write sentences with 10 words each Utility	95	92	90	90	90	79	79	77	72	68	83%
Write sentences with 20 words each Utility	76	72	68	68	67	61	58	57	54	29	61%
81.02%

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	0	0	0	0	0	0	0	0	0	10%
outline-count											70.00%
pov-count
Count point of views for Jack and Olivia Utility	50	50	0	0	0	0	0	0	0	0	10%
Count point of views for Jack Harper Utility	100	100	100	100	100	100	100	100	100	100	100%
Count point of views for Olivia Utility	100	100	100	0	0	0	0	0	0	0	30%
pov-count											46.67%
58.33%

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	97	97	96	96	96	96	96	96%
Expand all contractions Text Editing	98	98	98	98	98	98	98	98%
Location rename: market square, outer ring, bridge, northern mines Text Editing	96	96	96	96	96	96	96	96%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	100	100	100	100	100	100	99	100%
Passive voice → active voice Text Editing Hallucination	84	83	83	79	79	78	78	81%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	96	96	95	95	95	95	95	95%
Tense rewriting: past to present Text Editing	96	96	96	96	95	95	95	96%
Generic Prompt								95.76%
Specific 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	99	99	99	99	99	99	99	99%
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	97	97	97	99%
Passive voice → active voice Text Editing Hallucination	94	94	94	94	94	93	92	94%
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	100	100	100	100	100%
Specific Prompt								99.07%
97.41%

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	67	97%
96.67%

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	0	0	0	0	0	0	0	0	0	0	0%
Simple (1-shot) 1-shot Rule Following	100	100	0	0	0	0	0	0	0	0	20%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	100	100	100	100	100	0	90%
Unattributed dialogue Rule Following	0	0	0	0	0	0	0	0	0	0	0%
22.00%

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	100	100	100	98	98	98	99%
20 sentence summary Utility	100	100	100	100	100	98	98	92	77	0	87%
50 sentence summary Utility	100	100	100	100	100	100	100	100	100	100	100%
sentences											97.23%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
20 word summary Utility	100	100	98	98	92	92	92	77	77	54	88%
50 word summary Utility	100	100	100	100	98	98	92	92	92	77	95%
100 word summary Utility	100	92	92	92	77	9	0	0	0	0	46%
200 word summary Utility	77	27	9	0	0	0	0	0	0	0	11%
words											68.14%
86.68%