Service Tiers

Some models support service tiers — processing modes that let you pay less or get faster responses depending on your needs. Flex is a great default when you want to cut costs without sacrificing output quality.

Service tiers are a provider feature from OpenAI and Gemini — not something Routeway implements on its own. When you set a tier, Routeway forwards it to the upstream provider and applies the matching price multiplier on your bill. Routeway does not run a separate queue or priority system; any latency or capacity differences come from how the provider handles that tier.

Service tiers are currently available on select OpenAI and Gemini models only — not every model from those providers, and not models from other providers. Check the Models Catalog or the capabilities.service_tiers field in the GET /v1/models response to confirm a specific model supports them.

Available Tiers

Tier	Cost	Latency	Best for
Default	Standard model pricing	Balanced time-to-first-token (TTFT) and throughput	General production workloads
Flex	50% off standard pricing	Same generation speed once streaming starts; TTFT may occasionally be higher	Cost-sensitive workloads, high-volume usage, evals, batch jobs
Priority	2× standard pricing	Lower, more consistent TTFT on the provider side — even during peak demand	User-facing chat, real-time assistants, latency-sensitive apps

Flex does not reduce output quality or token generation speed. The main difference is that time-to-first-token can be a bit higher on some requests. If the upstream provider’s flex capacity is temporarily limited, the request may return 429 from the provider — you are not charged in that case.

Supported Models

Service tiers are currently supported on a subset of OpenAI and Gemini models. Availability varies by model — Routeway does not enable tiers on every model from those providers, and models from Anthropic, DeepSeek, and other providers do not support them yet.

Models Catalog

Open any model page on the Models Catalog and scroll to the bottom. If the model supports service tiers, you’ll see a Service Tiers section and tier-specific rates under Token Pricing. For example, GPT 5.6 Luna shows all three tiers with their multipliers:

GPT 5.6 Luna model page showing Service Tiers and Token Pricing for default, flex, and priority

If a model does not support tiers, those sections are omitted from its page.

API

Query the models endpoint and look for service_tier in supported_parameters and the tier list in capabilities.service_tiers:

curl https://api.routeway.ai/v1/models \
  -H "Authorization: Bearer $ROUTEWAY_API_KEY"

{
  "id": "gpt-5.6-luna",
  "owned_by": "openai",
  "supported_parameters": ["temperature", "tools", "service_tier", "..."],
  "capabilities": {
    "service_tiers": ["default", "flex", "priority"]
  },
  "service_tiers": {
    "flex": {
      "price_multiplier": 0.5,
      "note": "50% discount"
    },
    "priority": {
      "price_multiplier": 2.0,
      "note": "2x price"
    }
  }
}

Filter client-side to list all eligible models:

data = client.models.list()

tiered_models = [
    m for m in data.data
    if m.capabilities and getattr(m.capabilities, "service_tiers", None)
]

for m in tiered_models:
    print(m.id, "—", m.owned_by, "—", m.capabilities.service_tiers)

Service tiers apply to the listed per-token rates in the model’s pricing object. See How Billing Works for how multipliers affect your bill.

Setting a Service Tier

There are two ways to select a tier. Both produce the same result — use whichever fits your setup.

Option 1: `service_tier` Parameter

Pass service_tier in the request body. This is the recommended approach when you control the API payload.

Python
Node.js
cURL

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.routeway.ai/v1",
    api_key=os.getenv("ROUTEWAY_API_KEY")
)

# Flex — 50% cheaper
response = client.chat.completions.create(
    model="gpt-5.6-luna",
    messages=[{"role": "user", "content": "Summarize this dataset..."}],
    service_tier="flex",
)

# Priority — 2× cost, lower TTFT
response = client.chat.completions.create(
    model="gpt-5.6-luna",
    messages=[{"role": "user", "content": "Help me debug this error."}],
    service_tier="priority",
)

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.routeway.ai/v1",
  apiKey: process.env.ROUTEWAY_API_KEY,
});

// Flex — 50% cheaper
const flexResponse = await client.chat.completions.create({
  model: "gpt-5.6-luna",
  messages: [{ role: "user", content: "Summarize this dataset..." }],
  service_tier: "flex",
});

// Priority — 2× cost, lower TTFT
const priorityResponse = await client.chat.completions.create({
  model: "gpt-5.6-luna",
  messages: [{ role: "user", content: "Help me debug this error." }],
  service_tier: "priority",
});

# Flex
curl https://api.routeway.ai/v1/chat/completions \
  -H "Authorization: Bearer $ROUTEWAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-luna",
    "messages": [{"role": "user", "content": "Summarize this dataset..."}],
    "service_tier": "flex"
  }'

# Priority
curl https://api.routeway.ai/v1/chat/completions \
  -H "Authorization: Bearer $ROUTEWAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-luna",
    "messages": [{"role": "user", "content": "Help me debug this error."}],
    "service_tier": "priority"
  }'

Accepted values: "default", "flex", and "priority". Omit the parameter (or set "default") to use standard pricing and performance.

Option 2: Model Suffix

Append :flex or :priority to the model ID. This is useful in chat UIs and other tools where you cannot pass extra request parameters.

# Flex via model suffix
response = client.chat.completions.create(
    model="gpt-5.6-luna:flex",
    messages=[{"role": "user", "content": "Run this evaluation batch."}],
)

# Priority via model suffix
response = client.chat.completions.create(
    model="gpt-5.6-luna:priority",
    messages=[{"role": "user", "content": "What is the weather in Tokyo right now?"}],
)

Both approaches achieve the same result. Use service_tier when you have programmatic control over the request body, and the :flex / :priority suffix when you can only change the model name — for example in Open WebUI, SillyTavern, or other chat frontends.

Response Field

The response includes a service_tier field indicating which tier actually processed the request:

{
  "id": "chatcmpl-abc123",
  "model": "gpt-5.6-luna",
  "service_tier": "flex",
  "choices": [
    {
      "message": {
        "role": "assistant",
        "content": "Here is the summary..."
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 120,
    "completion_tokens": 85,
    "total_tokens": 205
  }
}

When to Use Each Tier

Default

Your everyday choice. Standard pricing with balanced performance for most production traffic.

Flex

Save 50% with the same output quality. Ideal when you want lower costs and can tolerate the occasional slower start — TTFT may be higher, but generation speed is unchanged.

Priority

Pay a premium for lower, more predictable TTFT when users are waiting on the first token in real time.

Get Started

Platform Details

Help & Resources

Core Concepts

Account Management

Guides

Available Tiers

Supported Models

Models Catalog

API

Setting a Service Tier

Option 1: `service_tier` Parameter

Option 2: Model Suffix

Response Field

When to Use Each Tier

Default

Flex

Priority

​Available Tiers

​Supported Models

​Models Catalog

​API

​Setting a Service Tier

​Option 1: service_tier Parameter

​Option 2: Model Suffix

​Response Field

​When to Use Each Tier

Default

Flex

Priority

Available Tiers

Supported Models

Models Catalog

API

Setting a Service Tier

Option 1: `service_tier` Parameter

Option 2: Model Suffix

Response Field

When to Use Each Tier