What Is an OpenAI-Compatible API? A Developer's Guide
An OpenAI-compatible API speaks the /v1/chat/completions contract. Learn what the spec guarantees, what it doesn't, and how to switch providers by changing base_url.
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Agentic API engineering notes
Engineering deep-dives, model benchmarks and product updates — straight from the team building the agentic API for every frontier model.
What is an agentic API?
An agentic API is an AI API built to support autonomous, multi-step workflows — not single prompt-response cycles. It manages session state, tool calls, and model routing across a sequence of actions, so an AI agent can plan, execute, and iterate without the developer scripting each step manually. Speka provides one agentic API endpoint that unifies access to every model in the catalog under a single integration.
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LLM API Gateway: What It Is and When You Need One
An LLM API gateway gives you one endpoint, one key, and one bill across providers. Learn what it does, when you need one, and how Speka compares.
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OpenAI-Compatible API: Ollama, vLLM, SGLang & TGI
Set up an OpenAI-compatible /v1/chat/completions endpoint with Ollama, vLLM, SGLang or TGI — exact commands, curl tests, a spec-coverage table, and when to switch to a hosted gateway.
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OpenAI-Compatible API Providers: 2026 Matrix
A June 2026 matrix of AI providers with OpenAI-compatible APIs: endpoints, streaming, tool calling, vision, and gotchas. Plus how Speka's gateway normalizes them.
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Free OpenAI-Compatible API: Best Options 2026
Compare free OpenAI-compatible APIs in 2026 — Speka, Hugging Face TGI, OpenRouter, Together AI. Real rate limits, free-tier caveats, and a drop-in code example.
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Connect LangChain, n8n, Dify & LlamaIndex to an OpenAI API
Point LangChain, n8n, Dify, and LlamaIndex at any OpenAI-compatible API. Exact base_url, key, and model config to connect each framework to Speka.
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Frequently asked questions
An agentic API is an AI API designed to support multi-step, autonomous workflows rather than single prompt-response calls. It manages session state, tool calls, and model routing across a sequence of actions — enabling AI agents to plan and execute tasks without the developer scripting each step manually. Speka provides one agentic API endpoint that gives developers unified access to frontier models through a single integration.
Speka provides unified access to frontier open-weight models including Llama 3.3, DeepSeek V4 Flash, Mistral, and FLUX through a single API endpoint. The model is passed as a parameter in each API call — switching between models requires no additional integration work.
The cheapest approach depends on token volume and model choice. For most development-scale workloads, a pay-per-token managed API is more cost-effective than self-hosting because it eliminates GPU server costs, ops overhead, and downtime risk. Self-hosting open-weight models typically becomes cheaper only at very high volumes — generally in the billions of tokens per month range.
Yes. Speka is designed specifically for agentic workflows — multi-step tasks where the AI needs to call tools, maintain context across turns, and switch between models depending on the task. The API supports streaming, tool-call patterns, and model switching through a single unified endpoint.