yelno.ai
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SDKs & OpenAI compatibility

Keep the OpenAI or Anthropic client you already have and change one URL — there is no separate Yelno SDK to install.

Official SDKs

LanguageInstallVersionNotes
Pythonpip install openai≥ 1.0OpenAI(base_url=…, api_key=…); yelno via res.model_extra
TypeScript / Nodenpm install openai≥ 4.0new OpenAI({ baseURL, apiKey }); edge-runtime safe
Gogo get github.com/openai/openai-go≥ 1.0option.WithBaseURL(…), option.WithAPIKey(…)
Java / Kotlincom.openai:openai-java≥ 1.0OpenAIOkHttpClient.builder() with baseUrl(…) and apiKey(…)
.NETdotnet add package OpenAI≥ 2.0OpenAIClientOptions { Endpoint = … }
Anthropic SDKspip install anthropic · npm install @anthropic-ai/sdklatestbase_url https://yelno.ai → POST /v1/messages

OpenAI compatibility

Attribute a request to a project with the OpenAI-Project header (or X-Yelno-Project) carrying the project id from the console — the OpenAI SDKs send it when you pass project=. It works with an organization-wide key and must name a project of the key's own organization; a key scoped to a project always uses that project. OpenAI-Organization is checked against the key and never selects an organization.

Point any OpenAI SDK at https://yelno.ai/v1. Model ids use the creator/model form. Route evidence and cost are returned in an additive yelno object that existing clients ignore, and every response carries an X-Request-Id header. Routing is not chosen per request: your organization's policy applies (/console/routing).

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://yelno.ai/v1",
  apiKey: process.env.YELNO_API_KEY,
  // no routing header: the organization policy in /console/routing applies to every request
});

const res = await client.chat.completions.create({
  model: "mistral/mistral-large-2",
  messages: [{ role: "user", content: "ping" }],
});
const { provider, attempts, cost } = (res as any).yelno;   // additive; typed clients ignore it
console.log(provider, attempts[0].region, cost.customer_nanos, cost.state);  // mistral eu-west 46000 final

Frameworks

LangChain / LangGraph
ChatOpenAI(base_url=…, api_key=…) with a creator/model id
Vercel AI SDK
createOpenAI({ baseURL, apiKey }) from @ai-sdk/openai · streaming and tool calls
LlamaIndex
OpenAILike(api_base=…) LLM and OpenAIEmbedding(api_base=…)
Spring AI
spring.ai.openai.base-url=https://yelno.ai
Pydantic AI
OpenAIProvider(base_url=…) with the OpenAI chat model class
Any OpenAI client
Change baseURL; nothing else
What differs from OpenAI Cost arrives in the response's yelno.cost with a state (final or provisional), never in headers. Parameters no eligible endpoint supports are omitted and reported in warnings[] by default (compat_mode: "permissive"); send compat_mode: "strict" to get a 422 naming the parameter before any provider is contacted.