Solar Open 2
Solar Open 2 is Upstage’s 250B-parameter open-weight model for document-heavy agents, office productivity, and coding. It activates 15B parameters per token and interleaves linear attention with standard attention to improve long-context inference efficiency. A 1M-token context supports large document collections and extended tool histories. Its release includes weights and a technical report describing training and evaluation. The custom Solar Open license governs redistribution and commercial use. Sparse activation lowers computation relative to a dense model of the same total size but does not eliminate the storage and memory requirements of the full weights.
2026-07-22
250B total, 15B active
Hybrid-attention Mixture of Experts
Solar Open Model License
Specifications
- Parameters
- 250B total, 15B active
- Architecture
- Hybrid-attention Mixture of Experts
- License
- Solar Open Model License
- Context Window
- 1,048,576 tokens
- Type
- text
- Modalities
- text
Benchmark Scores
Advanced Specifications
- Model Family
- Solar
- API Access
- Not Available
- Chat Interface
- Not Available
- Multilingual Support
- Yes
- Variants
- Solar-Open2-250B
Capabilities & Limitations
- Capabilities
- reasoningtool callingcodinglong context
- Known Limitations
- Custom model license appliesLong-context serving has substantial memory requirementsAgent execution depends on an external harness
- Notable Use Cases
- private enterprise agentsdocument workflowssoftware development
- Function Calling Support
- Yes
- Tool Use Support
- Yes
