Supported Models
CallStack AI Gateway provides unified access to leading foundation models through a single, standardized API interface.
Anthropic Claude
> Gateway Endpoint: claude.callaiapi.com
Claude Opus 4
Most capable model for complex reasoning, code generation, and deep analysis tasks.
NewClaude Sonnet 4
Optimal balance of performance and cost for production workloads.
ProductionClaude Haiku 3.5
High-speed, cost-efficient model for high-throughput processing tasks.
ProductionOpenAI GPT Series
> Gateway Endpoint: openai.callaiapi.com
GPT-4o
Flagship multimodal model supporting text, image, and audio inputs.
ProductionGPT-4o Mini
Lightweight, cost-optimized model for high-volume conversational workloads.
Productiono3 / o3-mini
Advanced reasoning models with built-in chain-of-thought for complex logic tasks.
NewGoogle Gemini
> Gateway Endpoint: gemini.callaiapi.com
Gemini 2.5 Pro
1M token context window with exceptional multimodal capabilities.
NewGemini 2.0 Flash
Ultra-fast inference with low latency, ideal for real-time applications.
ProductionAdditional Models
> DeepSeek: deepseek.callaiapi.com · Meta: meta.callaiapi.com · Mistral: mistral.callaiapi.com
DeepSeek V3 / R1
High-performance open-source models with strong multilingual capabilities.
ProductionLlama 3.1 405B
Meta's largest open model for enterprise-scale deployments.
ProductionMistral Large
European-built model with strong reasoning and multilingual performance.
ProductionModel Capabilities Matrix
| Model | Endpoint | Context | Multimodal | Streaming | Function Calling |
|---|---|---|---|---|---|
| Claude Opus 4 | claude.callaiapi.com | 200K | ✅ | ✅ | ✅ |
| Claude Sonnet 4 | claude.callaiapi.com | 200K | ✅ | ✅ | ✅ |
| GPT-4o | openai.callaiapi.com | 128K | ✅ | ✅ | ✅ |
| o3 | openai.callaiapi.com | 200K | ❌ | ✅ | ✅ |
| Gemini 2.5 Pro | gemini.callaiapi.com | 1M | ✅ | ✅ | ✅ |
| DeepSeek V3 | deepseek.callaiapi.com | 128K | ❌ | ✅ | ✅ |
::: tip Model Updates We continuously evaluate and onboard new models as they become available. For specific model requirements for your organization, contact our solutions team. :::