Gemini 2.5 Flash Lite (Reasoning)

google/gemini-2.5-flash-lite

Gemini 2.5 Flash Lite (Reasoning)

via OpenRouter

Release Date

Jul 22nd, 2025

Context Size

Reasoning

Yes

Benchmark Cost

$1.28

Speed

243.6 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 WritingHallucination	72	70	69	66	64	68%
Horror: alone in an eerie place at night Creative WritingHallucination	77	76	72	71	69	73%
Literary fiction: old friends reunite Creative WritingHallucination	76	76	75	73	68	74%
Mystery: examining a crime scene Creative WritingHallucination	72	71	68	66	65	68%
Romance: separated couple reunites Creative WritingHallucination	78	71	69	64	62	69%
Thriller: chase through city streets Creative WritingHallucination	79	78	76	74	70	76%
Detailed Writing Rules						71.32%
genre
Fantasy: entering an ancient ruin Creative WritingHallucination	69	67	66	62	60	65%
Horror: alone in an eerie place at night Creative WritingHallucination	78	72	71	70	68	72%
Literary fiction: old friends reunite Creative WritingHallucination	81	79	71	71	64	73%
Mystery: examining a crime scene Creative WritingHallucination	79	78	75	74	74	76%
Romance: separated couple reunites Creative WritingHallucination	78	77	75	70	67	73%
Thriller: chase through city streets Creative WritingHallucination	83	82	81	80	77	81%
genre						73.22%
Novelcrafter Default Prompt
Fantasy: entering an ancient ruin Creative WritingHallucination	68	68	67	64	63	66%
Horror: alone in an eerie place at night Creative WritingHallucination	76	74	70	62	61	69%
Literary fiction: old friends reunite Creative WritingHallucination	79	73	72	71	71	73%
Mystery: examining a crime scene Creative WritingHallucination	79	78	77	77	75	77%
Romance: separated couple reunites Creative WritingHallucination	76	74	73	70	66	72%
Thriller: chase through city streets Creative WritingHallucination	88	79	79	71	71	77%
Novelcrafter Default Prompt						72.41%
72.32%

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) ToolingReasoning	98	97	95	94	92	95%
Medium: The Hollow (Inferred) ToolingReasoning	97	96	95	95	94	95%
Medium: Through the Thornveil (Scattered) ToolingReasoning	93	93	92	88	88	91%
Short: The Rusty Lantern (Explicit) ToolingReasoning	99	97	94	92	91	95%
93.98%

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	100	25	93%
Long text (~1594 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	100	25	93%
Short text (~524 words), big codex (51 entries) Hallucination	100	100	100	100	100	100	100	100	100	100	100%
Short text (~524 words), small codex (11 entries) Hallucination	100	100	100	100	100	100	100	100	100	25	93%
basic entries											94.38%
detailed entries
Long text (~1594 words), big codex (51 detailed entries) Hallucination	100	100	100	100	100	100	100	100	100	25	93%
Long text (~1594 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	25	25	25	78%
Short text (~524 words), big codex (51 detailed entries) Hallucination	100	100	100	100	100	100	100	100	25	25	85%
Short text (~524 words), small codex (11 detailed entries) Hallucination	100	100	100	100	100	100	100	100	100	100	100%
detailed entries											88.75%
91.56%

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) ToolingReasoning	93	92	91	91	91	89	88	86	86	85	89%
Large codex (40 entries), short passage (165 words) ToolingReasoning	95	95	92	92	90	90	89	89	87	83	90%
Small codex (7 entries), long passage (734 words) ToolingReasoning	90	90	88	88	88	87	84	84	80	80	86%
Small codex (7 entries), short passage (165 words) ToolingReasoning	97	97	97	97	97	97	97	97	93	84	95%
matrix											90.11%
tiers
5 codex entries ToolingReasoning	100	100	100	100	100	100	100	93	93	93	98%
10 codex entries ToolingReasoning	100	100	94	94	94	94	94	92	92	92	95%
20 codex entries ToolingReasoning	94	94	94	94	92	91	91	88	86	86	91%
40 codex entries ToolingReasoning	100	100	100	97	97	97	97	97	93	90	97%
tiers											95.14%
92.63%

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	100	100	100	0	0	0	0	0	0	0	30%
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%
94.17%

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 FollowingUtility	96	95	60	53	52	50	47	0	0	0	45%
Write 200 words with 50% dialogue Rule FollowingUtility	99	50	50	50	50	30	28	24	4	0	39%
Write 200 words with 90% dialogue Rule FollowingUtility	99	58	50	50	49	46	42	40	32	18	48%
dialogue-200											44.09%
dialogue-500
Write 500 words with 30% dialogue Rule FollowingUtility	50	48	39	17	7	5	0	0	0	0	17%
Write 500 words with 50% dialogue Rule FollowingUtility	69	50	14	2	0	0	0	0	0	0	14%
Write 500 words with 70% dialogue Rule FollowingUtility	49	48	47	47	44	43	1	0	0	0	28%
dialogue-500											19.37%
Ungrouped
Write unattributed dialogue Rule Following	100	100	100	100	100	100	100	100	61	61	92%
40.36%

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	0	80%
Asking for directions (German) Language	100	100	100	100	0	80%
Friend got new kittens (German) Language	0	0	0	0	0	0%
Friend got new kittens (Tagalog) Language	100	100	100	100	100	100%
65.00%

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	90	0	78%
Character dialogue (Hindi) in a story Language	100	67	56	50	50	64%
Character dialogue (Italian) in a story Language	100	100	100	100	89	98%
Character dialogue (Spanish) in a story Language	100	100	100	100	0	80%
83.71%

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	99	98	98	98	97	97	96	98%
Write sentences with 10 words each Utility	95	87	87	84	83	75	68	43	40	30	69%
Write sentences with 20 words each Utility	67	65	55	53	52	49	35	25	13	10	42%
69.97%

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	100	0	90%
outline-count											96.67%
pov-count
Count point of views for Jack and Olivia Utility	100	100	100	100	100	100	100	100	100	50	95%
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											98.33%
97.50%

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	100	99	99	99	90	90	84	95%
Expand all contractions Text Editing	100	100	99	99	99	99	99	99%
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	74	74	74	74	73	73	77%
Passive voice → active voice Text EditingHallucination	97	96	95	95	94	94	93	95%
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	93	89	85	82	81	81	87%
Generic Prompt								94.74%
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	99	99	96	93	93	90	96%
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	100	100	100%
Multi-character gender swap: Priya(F)->Rohan(M), Mara unchanged Text Editing	100	100	99	99	93	86	0	83%
Passive voice → active voice Text EditingHallucination	99	98	98	98	96	95	81	95%
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	96	67	65	90%
Specific Prompt								95.79%
95.27%

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	100	100	100	100	100	100	100	100	100	0	90%
Simple Rule Following	100	100	100	100	0	0	0	0	0	0	40%
Simple (1-shot) 1-shot Rule Following	100	100	100	0	0	0	0	0	0	0	30%
Simple (5-shot) Few-shot Rule Following	100	100	100	100	100	100	100	100	100	0	90%
Unattributed dialogue Rule Following	100	100	100	100	100	100	100	100	100	100	100%
70.00%

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	100	100	100	100%
20 sentence summary Utility	100	100	100	100	100	100	100	100	98	92	99%
50 sentence summary Utility	100	100	100	100	98	92	92	77	77	0	84%
sentences											96.54%
words
10 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
20 word summary Utility	100	100	100	100	100	100	100	100	100	98	100%
50 word summary Utility	100	100	100	100	98	92	92	77	77	9	85%
100 word summary Utility	98	98	92	77	27	27	9	2	0	0	43%
200 word summary Utility	77	54	54	54	0	0	0	0	0	0	24%
words											70.25%
87.23%