---
language: en
license: apache-2.0
tags:
  - tool-routing
  - function-calling
  - prism-coder
  - qwen3.5
  - synalux
  - qlora
  - gguf
base_model: Qwen/Qwen3.5-9B
pipeline_tag: text-generation
---

# prism-coder:9b — Prism Memory Tool Router (Default Tier)

QLoRA fine-tuned [Qwen3.5-9B](https://huggingface.co/Qwen/Qwen3.5-9B) for MCP tool routing in the [Prism Coder](https://ollama.com/dcostenco/prism-coder) system. Replaces the previous 14B tier with 36% smaller footprint and higher accuracy.

## Quick Start

```bash
ollama pull dcostenco/prism-coder:9b
```

## BFCL Benchmark — 100% × 3 seeds

**64/64 × 3 shuffled runs = 100.0%, 0 hallucinations**

| Category | Count | Accuracy |
|----------|------:|:--------:|
| simple | 10 | 100% |
| relevance_detection | 10 | 100% |
| hallucination | 10 | 100% |
| disambiguation | 8 | 100% |
| format_sensitivity | 5 | 100% |
| ast_parameter | 5 | 100% |
| edge_case | 8 | 100% |
| multi_turn_chain | 8 | 100% |

### vs Previous 14B (Qwen 3)

| Metric | 14B (Qwen 3) | 9B (Qwen 3.5) |
|---|---|---|
| BFCL Overall | 90.3% | **100.0%** |
| Model Size | 9.0 GB | **5.8 GB** |
| Hallucinations | 0 | 0 |

## Training

- **Method**: QLoRA (4-bit base + bf16 adapters) on Apple Silicon M5 48GB
- **Base**: `mlx-community/Qwen3.5-9B-MLX-4bit` for training, `Qwen/Qwen3.5-9B` bf16 for merge
- **LoRA**: rank=32, alpha=64, 16 layers
- **Corpus**: 26K rows (40% AAC / 12% abstention / 12% safety / 36% tool-use)
- **Iterations**: 2000 at LR 1e-4
- **Layer 3**: Inference-time rules for tool remapping, param normalization, multi-turn chain parsing

## Architecture

Qwen3.5-9B uses a hybrid attention architecture:
- **Linear attention layers** (Gated DeltaNet) — O(n) inference, pattern matching
- **Full attention layers** (standard softmax) — precise retrieval and reasoning

## Fleet Position

| Model | Ollama tag | Size | BFCL | Role |
|---|---|---|---|---|
| Qwen3.5-2B Q3_K_M | `dcostenco/prism-coder:2b` | 2.3 GB | 99.1% | iPhone / mobile |
| Qwen3.5-4B Q4_K_M | `dcostenco/prism-coder:4b` | 3.4 GB | 100% | Verifier / 8 GB+ |
| **Qwen3.5-9B Q4_K_M** | **`dcostenco/prism-coder:9b`** | **5.8 GB** | **100%** | **Default router** |
| prism-coder:32b | `dcostenco/prism-coder:32b` | 19 GB | 100% | Complex tasks |

## Links

- [Ollama model page](https://ollama.com/dcostenco/prism-coder) — pull and run
- [Prism MCP Server](https://github.com/dcostenco/prism-coder) — the MCP server
- [Qwen3.5-9B base](https://huggingface.co/Qwen/Qwen3.5-9B) — upstream model