Smart Router Configuration & Cost Failover: GLM 5.3 Prime (z-ai/glm-5.3-prime) to Qwen3.8 Max Prime (qwen/qwen3.8-max-prime)

Production LLM API routing configuration, TTFT latency SLA (<400ms), and contribution margin failover benchmark generated by TokenMargin.dev.

1. Pricing & Latency Benchmark Summary

• Primary Model (GLM 5.3 Prime — z-ai/glm-5.3-prime): $2.80 / 1M input tokens, $8.80 / 1M output tokens | TTFT: 340ms | Throughput: 85 tok/s
• Fallback Model (Qwen3.8 Max Prime — qwen/qwen3.8-max-prime): $4.00 / 1M input tokens, $12.00 / 1M output tokens | TTFT: 340ms | Throughput: 85 tok/s

2. Zero-Dependency TypeScript / Node.js Smart Router Configuration

export const SMART_ROUTER_CONFIG = {
  slaMaxTtftMs: 400,
  primary: { model: "z-ai/glm-5.3-prime", inputPer1M: 2.80, outputPer1M: 8.80 },
  fallback: { model: "qwen/qwen3.8-max-prime", inputPer1M: 4.00, outputPer1M: 12.00 },
  retryOnStatus: [429, 500, 502, 503, 529]
};

3. LiteLLM / OpenRouter YAML Router Configuration (config.yaml)

model_list:
  - model_name: production-primary
    litellm_params:
      model: openrouter/z-ai/glm-5.3-prime
      timeout: 15
  - model_name: cost-fallback
    litellm_params:
      model: openrouter/qwen/qwen3.8-max-prime
router_settings:
  routing_strategy: latency-based-routing
  fallbacks: [{"production-primary": ["cost-fallback"]}]