GPT-OSS 120B - NC Bench

openai/gpt-oss-120b

GPT-OSS 120B

via OpenRouter

Release Date

Aug 5th, 2025

Context Size

131k

Reasoning

Yes

Benchmark Cost

$0.72

Speed

96.8 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	74	72	68	63	62	68%
Horror: alone in an eerie place at night Creative Writing Hallucination	71	68	66	65	63	67%
Literary fiction: old friends reunite Creative Writing Hallucination	77	74	73	71	69	73%
Mystery: examining a crime scene Creative Writing Hallucination	75	71	69	67	65	69%
Romance: separated couple reunites Creative Writing Hallucination	72	71	70	70	68	70%
Thriller: chase through city streets Creative Writing Hallucination	74	68	68	67	65	68%
Detailed Writing Rules						69.20%
genre
Fantasy: entering an ancient ruin Creative Writing Hallucination	66	65	63	63	60	63%
Horror: alone in an eerie place at night Creative Writing Hallucination	65	64	61	60	59	62%
Literary fiction: old friends reunite Creative Writing Hallucination	72	68	66	65	63	67%
Mystery: examining a crime scene Creative Writing Hallucination	70	67	66	65	64	67%
Romance: separated couple reunites Creative Writing Hallucination	68	68	67	65	60	65%
Thriller: chase through city streets Creative Writing Hallucination	67	65	63	63	57	63%
genre						64.43%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative Writing Hallucination	69	67	66	63	60	65%
Horror: alone in an eerie place at night Creative Writing Hallucination	66	65	62	61	58	63%
Literary fiction: old friends reunite Creative Writing Hallucination	73	72	70	67	66	70%
Mystery: examining a crime scene Creative Writing Hallucination	74	73	72	70	69	72%
Romance: separated couple reunites Creative Writing Hallucination	74	71	70	70	68	71%
Thriller: chase through city streets Creative Writing Hallucination	72	71	69	67	64	68%
Novelcrafter Default Prompt						68.00%
67.21%

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	95	94	92	92	91	93%
Medium: The Hollow (Inferred) Tooling Reasoning	97	97	96	92	91	95%
Medium: Through the Thornveil (Scattered) Tooling Reasoning	93	93	90	89	88	91%
Short: The Rusty Lantern (Explicit) Tooling Reasoning	97	97	95	95	95	96%
93.48%

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	100	100	100	100	100	100	100	100	25	25	85%
Long text (~1594 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	100	100	100%
Short text (~524 words), big codex (51 entries) Hallucination	100	100	100	100	100	100	25	25	25	25	70%
Short text (~524 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	25	25	85%
basic entries											85.00%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	100	100	100	100	25	25	25	25	25	25	55%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	100	100	25	93%
Short text (~524 words), big codex (51 detailed entries) Hallucination	100	100	100	100	100	100	100	100	100	100	100%
Short text (~524 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	100	100	100	100%
detailed entries											86.88%
85.94%

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	92	91	90	90	89	87	86	84	81	80	87%
Large codex (40 entries), short passage (165 words) Tooling Reasoning	95	93	93	93	93	92	90	90	89	89	92%
Small codex (7 entries), long passage (734 words) Tooling Reasoning	97	97	97	93	93	90	88	88	88	84	91%
Small codex (7 entries), short passage (165 words) Tooling Reasoning	100	100	97	97	97	97	97	97	97	93	97%
matrix											91.77%
tiers
5 codex entries Tooling Reasoning	100	100	100	100	100	100	93	93	93	93	97%
10 codex entries Tooling Reasoning	100	100	100	100	100	92	92	86	86	79	94%
20 codex entries Tooling Reasoning	89	89	88	86	85	85	81	77	74	74	83%
40 codex entries Tooling Reasoning	100	100	97	97	97	93	93	88	88	79	93%
tiers											91.76%
91.76%

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	100	100	100	100	100	100	100	100	100%
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%
91.67%

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	100	100	100	100	100	100	98	92	50	50	89%
Write 200 words with 50% dialogue Rule Following Utility	100	100	100	100	100	100	100	99	97	71	97%
Write 200 words with 90% dialogue Rule Following Utility	99	99	98	98	97	94	92	82	50	0	81%
dialogue-200											88.86%
dialogue-500
Write 500 words with 30% dialogue Rule Following Utility	97	83	38	26	18	16	0	0	0	0	28%
Write 500 words with 50% dialogue Rule Following Utility	100	99	57	50	49	34	26	22	3	2	44%
Write 500 words with 70% dialogue Rule Following Utility	50	48	48	40	39	24	15	10	1	1	28%
dialogue-500											33.19%
Ungrouped
Write unattributed dialogue Rule Following	100	100	100	100	100	100	61	14	14	0	69%
62.13%

Language Comprehension

Does the model understand more than just English?

Scenario	#1	#2	#3	#4	#5	Total
Asking for directions (Dutch) Language	100	100	100	100	100	100%
Asking for directions (German) Language	100	100	100	100	0	80%
Friend got new kittens (German) Language	100	100	100	100	100	100%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
95.00%

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	100	100	100	92	98%
Character dialogue (German) in a story Language	100	100	100	100	100	100%
Character dialogue (Hindi) in a story Language	100	100	100	100	100	100%
Character dialogue (Italian) in a story Language	100	100	100	100	92	98%
Character dialogue (Spanish) in a story Language	100	100	100	100	100	100%
99.36%

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	100	100	100	98	100%
Write sentences with 10 words each Utility	100	100	100	100	100	100	100	100	100	96	100%
Write sentences with 20 words each Utility	100	100	100	100	100	100	100	100	100	100	100%
99.80%

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	100	100	100	100	100	0	0	80%
outline-count											93.33%
pov-count
Count point of views for Jack and Olivia Utility	100	50	50	50	50	50	50	50	50	50	55%
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	100	100	100	100	100	100	100	100%
pov-count											85.00%
89.17%

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	89	89	89	95%
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	96	96	96	95	97%
Expand all contractions Text Editing	100	100	100	100	100	100	99	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	99	99	99	99	99	99	99	99%
Passive voice → active voice Text Editing Hallucination	94	92	92	92	91	90	79	90%
POV shift: 3rd person to 1st person (Elena's perspective) Text Editing	100	100	100	100	100	100	99	100%
Tense rewriting: past to present Text Editing	97	97	95	95	95	89	88	94%
Generic Prompt								97.23%
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	100	100	100	99	99	97	96	99%
Expand all contractions Text Editing	100	100	100	100	100	100	99	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	95	95	95	95	95	95	95	95%
Passive voice → active voice Text Editing Hallucination	98	98	97	96	95	52	52	84%
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	96	96	89	89	89	85	92%
Specific Prompt								96.61%
96.92%

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	100	100%
100.00%

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	100	100	100	0	0	0	0	0	50%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	0	0	0	0	0	0	40%
Unattributed dialogue Rule Following	100	100	100	100	100	100	100	100	100	100	100%
38.00%

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	100%
20 sentence summary Utility	100	100	100	100	100	100	98	98	92	92	98%
50 sentence summary Utility	100	100	100	100	100	100	98	92	77	0	87%
sentences											96.88%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	100	100%
20 word summary Utility	100	100	100	100	100	100	100	100	100	100	100%
50 word summary Utility	100	100	100	100	100	100	100	100	100	100	100%
100 word summary Utility	100	100	100	100	100	100	100	100	100	100	100%
200 word summary Utility	100	100	100	100	100	100	100	100	100	92	99%
words											99.84%
98.74%