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REST API Fundamentals for LLM Gateways
13 posts on rest api fundamentals for llm gateways — part of api integration on the n4n AI blog.
Why LLM gateways use API keys instead of OAuth
Explains why LLM gateways favor static API keys over OAuth flows: lower latency, simpler machine-to-machine auth, and easier metering, with tradeoffs.
What idempotency means for LLM API requests
Idempotency for LLM API requests means repeated calls with same key produce same effect. Learn how it works, why it matters, and common pitfalls.
Understanding rate limits and token buckets in LLM APIs
A precise engineer's guide to llm api rate limits token bucket: how token bucket algorithms shape LLM gateway throttling, with code and pitfalls.
Understanding pagination in LLM API list endpoints
LLM API pagination list endpoints split large result sets into pages via cursor or offset params, keeping list calls fast and predictable for clients.
REST vs streaming endpoints in LLM API design
A head-to-head comparison of REST and streaming LLM endpoints across cost, latency, ergonomics, and limits, with a verdict for engineers.
REST endpoint design patterns for multi-model routing
A practical guide to REST API multi-model routing design: collapse endpoints, use header directives for fallback, pass cache hints, and meter usage.
How LLM gateways bill for tokens versus requests
LLM gateway billing tokens vs requests: why per-token metering dominates API economics, how request fees creep in, and what to watch in your invoices.
How authentication works in OpenAI-compatible APIs
OpenAI compatible API authentication relies on bearer tokens in the Authorization header. Learn how keys, scopes, and gateways manage LLM access.
What is model fallback in an LLM API gateway
Model fallback in an LLM API gateway automatically reroutes requests to alternate models when primary providers fail, ensuring uptime and cost control.
What is an LLM API gateway, and why do you need one
What is an LLM API gateway? It's a proxy that unifies model provider APIs, adds routing and fallback. This explainer covers how it works and why.
Request and response shapes in chat completions
Define the chat completions request response shape for LLM REST APIs: message roles, parameters, streaming, and usage fields explained with code.
HTTP status codes every LLM API client should handle
A practical guide to handling LLM API HTTP status codes for gateways: which mean retry, which mean fail, and how to build a resilient client with backoff.
A beginner's guide to the OpenAI-compatible API standard
A practical openai compatible api standard guide for engineers: core endpoints, request shapes, pitfalls, and a migration path to LLM gateways.
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