LFM2.5-24B-A2B: Built for fast on-device agents
TL;DR Highlight
A 24B MoE with 2B active params matches 35B-class models on 5 of 8 agentic benchmarks.
Who Should Read
A backend developer who wants to run tool-calling agents locally because cloud API costs and data leakage are a concern
Core Mechanics
- 24B reasoning model with only 2B active
- It is an MoE (mixture of experts) that uses 2B of its 24B parameters per token.
- It is the largest and final model in the LFM2.5 family.
- Both the base and post-trained models are open-weight on Hugging Face.
- Ahead on 5 of 8 agentic benchmarks
- Against Qwen3.6-35B-A3B it scores 27.69 vs 8.72 on AutomationBench and 48.09 vs 38.19 on LiveClaw.
- It also leads or matches on BFCLv4, ToolSandbox, and τ³-Bench Banking.
- It leads all three instruction-following benchmarks (IFEval, IFBench, Multi-IF).
- Bigger models win on knowledge and coding
- GPQA Diamond is 74.42 vs 83.69 for Qwen3.6-35B-A3B.
- SWE-Bench Verified (OpenCode) is 51.00 vs 66.20.
- The post recommends pairing it with retrieval or web search for knowledge-heavy work.
- Fastest on-device among compared MoEs
- It decodes 184 tokens/s on an Apple M5 Max and 114 tokens/s on an AMD Ryzen AI Max+ 395.
Community Reactions
- Very fast on local GPUs, per commenters
- One user got 200-320 tok/s on a 5070ti with llama.cpp, 131k context, and no tuning.
- Another said it is very fast on a 4090 but also very dumb.
- Real agent work disappointed some users
- One user ran it via OpenRouter in OpenCode following a plan from a larger model and it got stuck on many tool calls.
- Another asked it to implement a simple todo in the ghostty codebase and it looped on compile errors, while Qwen 3.8 finished at 40 vs 75 tok/s.
- Knowledge is well below Qwen 35B, one commenter says
- In their private benchmark, general knowledge was much worse than Qwen 35B A3B.
- They still expect it to beat Qwen 9B at higher speed.
- No prompt caching in Ollama, one user found
- On a Ryzen 7 8745HS with Radeon 780M via Ollama Vulkan, they saw about 45 tok/s generation and about 680 tok/s prompt processing.
- Ollama forced full prompt re-processing each time, so it was unusable in an agentic loop.
How to Apply
- Run a local tool-calling smoke test with llama.cpp
- Download the GGUF checkpoint from Hugging Face and serve it with llama.cpp today.
- Try 3-5 tool schemas from your current agent and measure the call success rate.
- Check whether it gets stuck on tool calls, as commenters reported.
- Attach a search tool for knowledge-heavy tasks
- Check prompt caching on your serving stack
- Before using it in an agent loop, send the same system prompt twice and check that prefill time drops on the second call.
- If it does not, compare against other runtimes like vLLM or llama.cpp.
- Check the license before adopting
- Read the commercial-use threshold in the model license.
- Ask legal whether internal local tooling counts.
Try It
# Paste into Claude or ChatGPT to build a local agent eval set
Our agent uses the tools below.
{{tool list and JSON schemas}}
Create 20 test cases as JSON to verify whether a small on-device model calls tools correctly.
- Include 8 single-tool cases, 6 cases needing 2-3 tools in sequence, 3 questions that need no tool, and 3 cases where information is missing and the model should ask back
- Give each case user_message, expected_tool_calls, and pass criteria
Next step: run these cases on local LFM2.5-24B-A2B and on your current model, then compare pass rates.Terminology
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