Mistral · Open weights
Devstral 2 123B
Devstral 2 123B is a 123 billion parameter model from Mistral AI optimized for coding and development tasks. Features advanced reasoning capabilities for software engineering workflows.
- Input
- Text
- Output
- Text
- Discovery tier
- Open weights
Pricing
USD per 1M tokens- Input
- $0.40
- Output
- $1.40
Reference prices as published by the model provider. API example
Specifications
- Context window
- 262.1K
- Max output
- 65.5K
- Average output (7 days)
- 120 tokens
- Longer than 11% of 468 models
Side by side
Devstral 2 123B compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| Devstral 2 123BMistralThis model | Gemini 2.0 Pro 0205GoogleRemove | |
|---|---|---|
| Provider | Mistral | |
| Discovery tier | Open weights | Balanced |
| Added | Dec 9, 2025 | Feb 5, 2025 |
| Limits | ||
| Context window | 262.14K | 2.1MBest |
| Max output | 65.54KBest | 8.19K |
| Average output | 120 tokens | — |
| Pricing, USD per 1M tokens | ||
| Input | $0.40Best | $1.99 |
| Output | $1.40Best | $7.96 |
| Cache read | — | $0.50 |
| Performance | ||
| Request success (24h) | 99.7% | — |
| Benchmark indexes | ||
| Intelligence Index | 8.6 | 8.7Best |
| Coding Index | 31.3Best | 25.5 |
| Math Index | 36.7 | — |
| Capabilities | ||
| Vision | No | Yes |
| Audio input | No | Yes |
| Reasoning effort | — | — |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- Devstral 2 123B
- Gemini 2.0 Pro 0205
Intelligence Index
- Devstral 2 123B8.6
- Gemini 2.0 Pro 02058.7
Devstral 2 123B: Better than 15% of 326 scored models
Indexes
Coding Index
Composite of the coding evaluations
- Devstral 2 123B: 31.3Top
- Gemini 2.0 Pro 0205: 25.5
Math Index
Composite of the math evaluations
- Devstral 2 123B: 36.7
- Gemini 2.0 Pro 0205: —
Agentic work
AutomationBench-AA
Workflow automation, penalized for guardrail violations
- Devstral 2 123B: 3.1%
- Gemini 2.0 Pro 0205: —
AutomationBench-AA tasks completed
Workflows finished end to end without a guardrail violation
- Devstral 2 123B: 0.0%
- Gemini 2.0 Pro 0205: —
AA-Briefcasev1.1
Agentic knowledge work, rated head to head
- Devstral 2 123B: 482 Elo
- Gemini 2.0 Pro 0205: —
GDPval-AAv2.1
Economically valuable occupational tasks, rated head to head
- Devstral 2 123B: 544 Elo
- Gemini 2.0 Pro 0205: —
Document reasoning
GDP.pdf
Professional reasoning over PDF documents, all-pass rate
- Devstral 2 123B: 2.4%
- Gemini 2.0 Pro 0205: —
AA-LCRv1.1
Reasoning across long documents
- Devstral 2 123B: 32.3%
- Gemini 2.0 Pro 0205: —
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- Devstral 2 123B: 3.6%
- Gemini 2.0 Pro 0205: 6.2%Top
GPQA Diamond
Graduate-level science questions
- Devstral 2 123B: 59.4%
- Gemini 2.0 Pro 0205: 62.2%Top
MMLU-Pro
Multi-subject knowledge and reasoning
- Devstral 2 123B: 76.2%
- Gemini 2.0 Pro 0205: 80.5%Top
IFBench
Following precise output instructions
- Devstral 2 123B: 38.1%
- Gemini 2.0 Pro 0205: —
Coding
Terminal-Benchv4.0
Practical software engineering in a terminal
- Devstral 2 123B: 0.0%
- Gemini 2.0 Pro 0205: —
SciCode
Scientific computing in Python
- Devstral 2 123B: 32.8%
- Gemini 2.0 Pro 0205: —
LiveCodeBench
Recent competitive programming problems
- Devstral 2 123B: 44.8%Top
- Gemini 2.0 Pro 0205: 34.7%
Math
AIME 2025
Competition mathematics, 2025 problems
- Devstral 2 123B: 36.7%
- Gemini 2.0 Pro 0205: —
AIME
Competition mathematics
- Devstral 2 123B: —
- Gemini 2.0 Pro 0205: 36.0%
MATH-500
Competition math problems
- Devstral 2 123B: —
- Gemini 2.0 Pro 0205: 92.3%
Legacy evaluations
Terminal-Bench Hard
Earlier terminal task suite
- Devstral 2 123B: 18.9%
- Gemini 2.0 Pro 0205: —
τ²-Bench Telecom
Tool use in a customer-support simulation
- Devstral 2 123B: 24.9%
- Gemini 2.0 Pro 0205: —
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- Devstral 2 123B: 32.3%
- Gemini 2.0 Pro 0205: —
Scores from Artificial Analysis, updated Oct 26, 2026. Artificial Analysis
- Devstral 2 123B
- Gemini 2.0 Pro 0205
| Leaderboard | Devstral 2 123B | Gemini 2.0 Pro 0205 |
|---|---|---|
| Vision Style Control · Creative Writing | Not in top 20 | #5 · 1262.4 |
Ranks among Noumen catalog models on LMArena leaderboards. Only top-20 placements are listed.LMArena
- Devstral 2 123B
- Gemini 2.0 Pro 0205
| Leaderboard | Devstral 2 123B | Gemini 2.0 Pro 0205 |
|---|---|---|
| SWE-bench Verified | Not in top 20 | #12 · 57.6% |
Ranks among Noumen catalog models on Epoch AI leaderboards. Only top-20 placements are listed.Epoch AI
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Prompt cache hits
- 0.0%
- Request success (24h)
- 99.7%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "mistralai/devstral-2-123b-instruct-2512",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="mistralai/devstral-2-123b-instruct-2512",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Mistral
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