--- license: apache-2.0 base_model: openbmb/MiniCPM5-2B pipeline_tag: text-generation library_name: coreai tags: - coreai - core-ai - coreml - apple - on-device - iphone - metal base_model_relation: quantized --- Core AI is Apple's on-device ML runtime in iOS 27 / macOS 27 and the successor to Core ML: PyTorch models are exported with Apple's `coreai-torch` (LLMs: `coreai.llm.export`) into `.aimodel` bundles that run on the GPU or the Neural Engine, e.g. Qwen3-8B 4-bit decodes at 94 tok/s on an M4 Max GPU, MLX 90 under the same protocol ([apple-silicon-llm-bench](https://github.com/john-rocky/apple-silicon-llm-bench), macOS 27 beta, 2026-06). This model has no row on [DeviceMark](https://devicemark.github.io/), the on-device LLM leaderboard. # MiniCPM5-2B — Core AI (int8 block-32, runs on iPhone) Apple **Core AI** (`.aimodel`) conversion of [openbmb/MiniCPM5-2B](https://huggingface.co/openbmb/MiniCPM5-2B) — OpenBMB's 2.5B on-device LLM (released 2026-09-06, the 1B's 42-layer sibling) with **hybrid Think / No-Think reasoning**, native tool calling and **128K** context; OpenBMB reports it as 2B-class open-source SOTA (LiveCodeBench v6 69.1, AIME 2026 86.5, BFCL v4 66.6, SWE-bench Verified 46.4 on their card). Runs fully on-device on **iPhone** and Apple Silicon Macs (GPU, pipelined engine). Part of the community Core AI model zoo: **https://github.com/john-rocky/coreai-model-zoo** ## Use it ⚡ **One line** — run the kit's task op on this model (`import CoreAIOps`; no session, no model plumbing, downloads on first use): ```swift let tldr = try await CoreAI.summarize(text, options: .model("minicpm5-2b")) ``` Every op, one shape — [Cookbook](https://github.com/john-rocky/coreai-kit/blob/main/docs/COOKBOOK.md). ▶️ **Run it (source)** — the [ChatDemo runner](https://github.com/john-rocky/coreai-kit/tree/main/Examples/ChatDemo) (GUI + CLI, one app for every chat model in the catalog): ```bash git clone https://github.com/john-rocky/coreai-kit open coreai-kit/Examples/ChatDemo/ChatDemo.xcodeproj # → Run, then pick "MiniCPM5 2B" in the model picker # agents / headless (macOS): cd coreai-kit/Examples/ChatDemo swift run chat-cli --model minicpm5-2b --prompt "What can you do, offline?" ``` 💻 **Build with it** — complete; the glue is kit API, copy-paste runs: ```swift import CoreAIKit let chat = try await ChatSession(catalog: "minicpm5-2b") let reply = try await chat.respond(to: prompt) // reply: the answer, generated fully on-device ``` The take-home is [`Examples/ChatDemo/Sources/QuickStart.swift`](https://github.com/john-rocky/coreai-kit/blob/main/Examples/ChatDemo/Sources/QuickStart.swift) — this exact code as one typed function, no UI; the CLI is an argument shell over it, and the GUI drives the same `ChatSession` across turns for its transcript. Multi-turn? Hold the `ChatSession` and call `respond(to:)` per turn — it keeps the conversation history; `streamResponse(to:)` yields tokens as they decode. **Integration checklist** - SPM: `https://github.com/john-rocky/coreai-kit` → product **CoreAIKit** - Info.plist: none needed - Entitlements: none on Mac; iPhone needs `com.apple.developer.kernel.increased-memory-limit` (the 2.7 GB cold specialization passes the default jetsam limit) - First run downloads the model — 2.7 GB (Mac) / 2.7 GB (iPhone) — then it loads from the local cache (Application Support; progress via the `downloadProgress` callback) - Measure in Release — Debug is ~3× slower on per-token host work ## Measured | | decode | prefill | numerics | size | |---|---:|---:|---|---:| | **iPhone 17 Pro** (A19 Pro, `PipelinedBench`, Release) | **22.4 tok/s** | 27.3 tok/s | **24/24 + 24/24 token-exact** vs HF fp32 (nat + oracle, the margin-clean alphabet prompt); engine ready 28.9 s cold | **2.7 GB** | | **M4 Max** (macOS 27, `llm-benchmark`) | **127.6 tok/s** | 2654 tok/s | **16/16 token-exact** vs the fp32 oracle (margin-aware gate, min margin 0.925) | | Free-run check (4 prompts × 30 greedy tokens vs fp32 HF, `verify_minicpm5.py`): **3/4 exact**; the one miss is a name at fp32 probability 0.2126 vs 0.2065 (`Emma`/`Lily`, top-2 margin 0.006) — a tie any precision may flip. The fp16 control export scores 4/4, and the **per-channel** int8 sibling of this bundle scored 2/4 with a real 0.245-margin flip (`,`→` and`), which is why this repo ships per-**block-32** scales instead (same recipe, three YAML lines; see *Quantization*). ⚠️ **iPhone context cap: prompt + generated tokens must stay under 1024.** The bundle declares a 131072 dynamic KV, and the shipped `CoreAIPipelinedEngine` caps iOS growing-KV capacity at 1024 (its guard against the iOS compiler miscompiling growing-KV specializations at seq ≥ 2048) — so a phone conversation truncates at absolute position 1024. Chunk or trim the history on iOS; macOS has no cap. Same recipe as the published [MiniCPM5-1B](https://huggingface.co/mlboydaisuke/MiniCPM5-1B-CoreAI) (int8 66.8 tok/s on the same phone) with one YAML changed — **per-block-32 scales instead of per-channel**. Measured on the Mac before picking it (`llm-benchmark`, 512p/1024g): int8 per-channel 25.6 tok/s, fp16 80.0, int8 per-block-32 **127.6**. Per-channel int8 lowers to a slow dequant path on the Mac GPU; block-32 lands on the fast quantized-matmul path, 5× the per-channel decode and 1.6× fp16's, at +155 MB. On the phone the two decode the same (bandwidth-bound), so block-32 wins on both. ## Quantization Weight-only **symmetric int8, per-block-32** (a scale per 32-wide block along the input dim; no clipping), applied as a torch pre-export pass via `coreai-opt`; SDPA / RoPE / RMSNorm stay full precision. The 1B ships the per-channel version of the same config. ```bash uv run coreai.llm.export openbmb/MiniCPM5-2B --experimental --compute-precision float16 \ --compression-config minicpm5_int8sym_b32.yaml # minicpm5_int8sym_b32.yaml: quantization_config → op_state_spec.weight = {dtype: int8, # qscheme: symmetric, granularity: {type: per_block, block_size: 32}} ``` ## Conversion notes - **`llama → mistral` remap.** MiniCPM5-2B's `model_type` is `llama` (a plain `LlamaForCausalLM`: 42 layers × hidden 2048, GQA 16:2, `head_dim` 128, RoPE θ 5e6, untied 130560-vocab head); the stock exporter has no `llama` graph family, but Mistral's builder is architecturally identical for this config (GQA, no qkv bias, no qk-norm, explicit `head_dim` honored). One-line remap in the model registry — the same line that ships the 1B. - **Chat EOS.** Base `eos_token` is ``, but the chat template ends turns with `<|im_end|>` (id 130073). The bundle's tokenizer `eos_token` is set to `<|im_end|>` (as Qwen ships) so generation halts cleanly — checked through the engine with the chat template applied: the model thinks, answers, and stops (124-token reply, 131.6 tok/s short-context on the M4 Max, on the published bundle). - **Dynamic-shape bundle** → the Core AI pipelined engine (the iPhone path); a static iOS export routes to the static-shape engine instead, which this FM-format bundle doesn't target. The 2.67 GB single-file bundle cold-specializes on the phone in 28.9 s (no AOT); that step needs the increased-memory entitlement and ~3 GB of free phone storage. - **Thinking.** The model thinks by default (`` before the answer); pass `enable_thinking=False` through the chat template for a direct answer. Give generation a generous budget (the kit caps at 4096) — the think trace alone can run several hundred tokens. ## Run ```swift import FoundationModels import CoreAILanguageModels let model = try await CoreAILanguageModel(resourcesAt: int8BundleURL) // …/int8 let session = LanguageModelSession(model: model) print(try await session.respond(to: "Explain on-device AI in one sentence.")) ``` Or in the zoo's **CoreAIChat** app / the kit's **ChatDemo** (Model → "MiniCPM5 2B"). ## Reproduce Exporter, gate, card and port notes live in the [Core AI model zoo](https://github.com/john-rocky/coreai-model-zoo): [`models/minicpm5-2b/`](https://github.com/john-rocky/coreai-model-zoo/tree/main/models/minicpm5-2b), [`conversion/export_minicpm5.py`](https://github.com/john-rocky/coreai-model-zoo/blob/main/conversion/export_minicpm5.py), [`knowledge/minicpm5-1b.md`](https://github.com/john-rocky/coreai-model-zoo/blob/main/knowledge/minicpm5-1b.md). ```bash python3 conversion/zoo_convert.py show minicpm5-2b python3 conversion/zoo_convert.py run minicpm5-2b ``` ## Credits Model: **MiniCPM5-2B** by **OpenBMB** ([openbmb/MiniCPM5-2B](https://huggingface.co/openbmb/MiniCPM5-2B), Apache-2.0). Core AI conversion: the Core AI model zoo.