MiMo-V2.5-Pro
Overview
MiMo-V2.5-Pro is an open-weight text model from Xiaomi MiMo that entered public beta on April 23, 2026. The higher-capacity member of the MiMo-V2.5 family uses a 1.02-trillion-parameter sparse Mixture-of-Experts (MoE) architecture with 42 billion active parameters and is designed for long-horizon agents, software engineering, and complex reasoning.
Key Features
- 1.02T Sparse MoE Architecture: Uses 1.02 trillion total parameters, 42 billion active parameters, 384 routed experts, and eight selected experts per token.
- Hybrid Long-Context Attention: Interleaves 60 Sliding Window Attention layers with 10 global-attention layers and a 128-token sliding window. Xiaomi reports that the 6:1 local-to-global pattern reduces KV-cache storage by nearly 7x.
- 1M Context and 128K Output: Supports a one-million-token context window and up to 128K output tokens for repository-scale work, long documents, and extended agent trajectories.
- Agent and Coding Evaluation: Xiaomi reports 1,581 Elo on GDPVal-AA, 63.8 on ClawEval, 57.2 on SWE-Bench Pro, 78.9 on SWE-Bench Verified, and 68.4 on Terminal-Bench 2.0.
- Controllable Reasoning and Tools: Deep thinking is enabled by default but can be disabled. The API supports streaming, function calling, and structured output.
Best Use Cases
- Long-Horizon Software Engineering: Repository navigation, multi-file implementation, debugging, testing, and tool-driven work that must remain coherent across long trajectories.
- Complex Agent Workflows: Tasks involving repeated function calls, planning, execution, and correction over large working contexts.
- Long-Document Reasoning: Analysis and synthesis across extensive code, technical documents, research material, or conversation history.
- Self-Hosted Model Development: Commercial inference, fine-tuning, or secondary training where MIT-licensed weights and framework-level deployment control are required.
Capabilities and Limitations
| Capability | Description |
|---|---|
| Reasoning | Deep thinking is enabled by default and can be turned off with thinking.type. Xiaomi reports 48.0 on Humanity's Last Exam with tools and 34.0 without tools. |
| Coding | Xiaomi reports 57.2 on SWE-Bench Pro, 78.9 on SWE-Bench Verified, 68.4 on Terminal-Bench 2.0, and an implementation rank of 3.4 on FrontierSWE. |
| Creative Writing | Supports general and long-form text generation. |
| Multimodal | Text input and text output. |
| Context Window | 1M tokens. |
| Max Output | 128K tokens. |
| Tool Use | Supports function calling, structured output, streaming, and Xiaomi's web-search tool. In thinking-mode agent conversations, tool-call history must retain the complete reasoning_content field. |
| Multilingual | The official model repository identifies English and Chinese support. Xiaomi reports 83.6 on GlobalMMLU, 91.5 on C-Eval, and 90.2 on CMMLU for the Pro Base model, but does not publish a complete language-support list. |
Known Limitations
mimo-v2.5-prois a text model and does not provide the full-modal understanding available inmimo-v2.5.- In thinking mode, custom
temperatureandtop_pvalues are ignored; the API forces1.0and0.95. Multi-turn tool workflows that omit historicalreasoning_contentcan fail with HTTP 400 or lose context quality.
Pricing
| Model | Input (Credits/Token) | Cache Write (Credits/Token) | Cache Read (Credits/Token) | Output (Credits/Token) | Web Search (Credits/Use) |
|---|---|---|---|---|---|
| MiMo-V2.5-Pro | 0.435 | 0.435 | 0.0036 | 0.87 | - |
Pricing note
Prices shown in the documentation are B.AI standard reference prices for base billing purposes. B.AI may provide lower actual usage costs through top-up bonuses and account benefits. Specific prices, bonus Credits, and account benefits are subject to the platform display and final billing records.