freellmapi-proxy
Original:🇺🇸 English
Translated
OpenAI-compatible proxy aggregating 14 free-tier LLM providers with automatic failover and per-key rate tracking.
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Sourcearadotso/trending-skills
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NPX Install
npx skill4agent add aradotso/trending-skills freellmapi-proxyTags
Translated version includes tags in frontmatterSKILL.md Content
View Translation Comparison →FreeLLMAPI Proxy
Skill by ara.so — Daily 2026 Skills collection.
FreeLLMAPI is a self-hosted OpenAI-compatible proxy that aggregates free-tier API keys from ~14 AI providers (Google, Groq, Cerebras, SambaNova, NVIDIA, Mistral, OpenRouter, GitHub Models, Hugging Face, Cohere, Cloudflare, Zhipu, Moonshot, MiniMax) behind a single endpoint. It handles automatic failover on 429/5xx, per-key rate tracking, sticky sessions for multi-turn conversations, and AES-256-GCM encrypted key storage.
/v1/chat/completionsInstallation
Prerequisites: Node.js 20+, npm.
bash
git clone https://github.com/tashfeenahmed/freellmapi.git
cd freellmapi
npm install
# Generate encryption key and set up environment
cp .env.example .env
echo "ENCRYPTION_KEY=$(node -e "console.log(require('crypto').randomBytes(32).toString('hex'))")" >> .env
# Development (server + Vite dashboard on :5173)
npm run dev
# Production build
npm run build
node server/dist/index.js # serves API + dashboard on :3001Environment Variables
bash
# .env
ENCRYPTION_KEY=<64-char hex string> # Required — AES-256 key for provider key storage
PORT=3001 # Optional — defaults to 3001
NODE_ENV=production # OptionalNever commit . The protects all stored provider API keys.
.envENCRYPTION_KEYKey Commands
bash
npm run dev # Start Express server + Vite dashboard in watch mode
npm run build # Compile TypeScript server + build React dashboard
npm run lint # ESLint across server/ and client/
npm run test # Run test suiteProvider Setup
- Open the dashboard at (dev) or
http://localhost:5173(prod).http://localhost:3001 - Navigate to Keys page.
- Add raw API keys for each provider you have. Keys are encrypted before SQLite storage.
- Navigate to Fallback Chain to reorder provider priority.
- Copy your unified bearer token from the Keys page header.
freellmapi-…
Supported providers and what to put in:
| Provider | Where to get a free key |
|---|---|
| Google Gemini | https://ai.google.dev |
| Groq | https://groq.com |
| Cerebras | https://cerebras.ai |
| SambaNova | https://cloud.sambanova.ai |
| NVIDIA NIM | https://build.nvidia.com |
| Mistral | https://mistral.ai |
| OpenRouter | https://openrouter.ai |
| GitHub Models | https://github.com/marketplace/models |
| Hugging Face | https://huggingface.co |
| Cohere | https://cohere.com |
| Cloudflare Workers AI | https://developers.cloudflare.com/workers-ai |
| Zhipu | https://bigmodel.cn |
| Moonshot | https://platform.moonshot.cn |
| MiniMax | https://platform.minimax.io |
Using the API
Python (openai SDK)
python
from openai import OpenAI
client = OpenAI(
base_url="http://localhost:3001/v1",
api_key="freellmapi-your-unified-key", # from dashboard Keys page
)
# Let the router pick the best available provider
response = client.chat.completions.create(
model="auto",
messages=[{"role": "user", "content": "Explain async/await in Python in two sentences."}],
)
print(response.choices[0].message.content)
# Which provider actually served this request:
print("Routed via:", response.headers.get("x-routed-via"))Request a specific model
python
# Request a specific model — router finds a provider that has it
response = client.chat.completions.create(
model="gemini-2.5-flash",
messages=[{"role": "user", "content": "Write a haiku about SQLite."}],
)Streaming
python
stream = client.chat.completions.create(
model="auto",
messages=[{"role": "user", "content": "List 5 TypeScript best practices."}],
stream=True,
)
for chunk in stream:
delta = chunk.choices[0].delta.content
if delta:
print(delta, end="", flush=True)
print()curl
bash
# Non-streaming
curl http://localhost:3001/v1/chat/completions \
-H "Authorization: Bearer $FREELLMAPI_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "auto",
"messages": [{"role": "user", "content": "Hello"}]
}'
# Streaming
curl http://localhost:3001/v1/chat/completions \
-H "Authorization: Bearer $FREELLMAPI_KEY" \
-H "Content-Type: application/json" \
--no-buffer \
-d '{
"model": "auto",
"messages": [{"role": "user", "content": "Count to 5 slowly"}],
"stream": true
}'
# List available models
curl http://localhost:3001/v1/models \
-H "Authorization: Bearer $FREELLMAPI_KEY"TypeScript / Node.js
typescript
import OpenAI from "openai";
const client = new OpenAI({
baseURL: "http://localhost:3001/v1",
apiKey: process.env.FREELLMAPI_KEY,
});
async function chat(userMessage: string): Promise<string> {
const response = await client.chat.completions.create({
model: "auto",
messages: [{ role: "user", content: userMessage }],
});
return response.choices[0].message.content ?? "";
}
// Streaming version
async function streamChat(userMessage: string): Promise<void> {
const stream = await client.chat.completions.create({
model: "auto",
messages: [{ role: "user", content: userMessage }],
stream: true,
});
for await (const chunk of stream) {
const delta = chunk.choices[0]?.delta?.content;
if (delta) process.stdout.write(delta);
}
console.log();
}Tool Calling
Tool calling works across all supported providers. OpenAI-compatible providers receive requests verbatim; Gemini requests are automatically translated to / format and back.
functionDeclarationsfunctionResponsepython
from openai import OpenAI
client = OpenAI(
base_url="http://localhost:3001/v1",
api_key="freellmapi-your-unified-key",
)
tools = [
{
"type": "function",
"function": {
"name": "get_weather",
"description": "Get current weather for a city.",
"parameters": {
"type": "object",
"properties": {
"city": {"type": "string", "description": "City name"},
},
"required": ["city"],
},
},
}
]
# Step 1: Model requests a tool call
first = client.chat.completions.create(
model="auto",
messages=[{"role": "user", "content": "What's the weather in Karachi?"}],
tools=tools,
tool_choice="required",
)
call = first.choices[0].message.tool_calls[0]
print(f"Tool requested: {call.function.name}({call.function.arguments})")
# Step 2: Execute the tool locally, feed result back
final = client.chat.completions.create(
model="auto",
messages=[
{"role": "user", "content": "What's the weather in Karachi?"},
first.choices[0].message, # assistant message with tool_calls
{
"role": "tool",
"tool_call_id": call.id,
"content": '{"temp_c": 32, "condition": "sunny"}',
},
],
tools=tools,
)
print(final.choices[0].message.content)Streaming tool calls
python
stream = client.chat.completions.create(
model="auto",
messages=[{"role": "user", "content": "What's the weather in Karachi?"}],
tools=tools,
tool_choice="required",
stream=True,
)
tool_call_chunks = []
for chunk in stream:
delta = chunk.choices[0].delta
if delta.tool_calls:
tool_call_chunks.extend(delta.tool_calls)
if chunk.choices[0].finish_reason == "tool_calls":
print("Tool call complete — assemble chunks and execute")Multi-turn Conversations (Sticky Sessions)
The proxy keeps multi-turn conversations on the same model for 30 minutes to avoid hallucination spikes from mid-conversation model switches. Pass a consistent in requests if the provider supports it, or rely on the proxy's automatic session tracking.
session_idpython
messages = [{"role": "system", "content": "You are a helpful coding assistant."}]
# Turn 1
messages.append({"role": "user", "content": "Write a Python function to flatten a nested list."})
resp1 = client.chat.completions.create(model="auto", messages=messages)
assistant_msg = resp1.choices[0].message
messages.append({"role": "assistant", "content": assistant_msg.content})
print(assistant_msg.content)
# Turn 2 — sticky session keeps same provider
messages.append({"role": "user", "content": "Now add type hints to that function."})
resp2 = client.chat.completions.create(model="auto", messages=messages)
print(resp2.choices[0].message.content)LangChain Integration
python
from langchain_openai import ChatOpenAI
from langchain_core.messages import HumanMessage
import os
llm = ChatOpenAI(
model="auto",
openai_api_base="http://localhost:3001/v1",
openai_api_key=os.environ["FREELLMAPI_KEY"],
streaming=True,
)
response = llm.invoke([HumanMessage(content="Summarise the CAP theorem in one paragraph.")])
print(response.content)Response Headers
Every response includes diagnostic headers:
| Header | Description |
|---|---|
| |
| Number of providers tried before success (only present if > 0) |
python
response = client.chat.completions.create(
model="auto",
messages=[{"role": "user", "content": "hi"}],
)
# Headers are on the raw httpx response:
raw = response._response # openai SDK exposes underlying httpx response
print(raw.headers.get("x-routed-via")) # e.g. "groq/llama-4-scout"
print(raw.headers.get("x-fallback-attempts")) # e.g. "2"How the Router Works
Request arrives
│
▼
Router scans fallback chain (priority order)
│
├─ For each model: is there a healthy key under all rate caps?
│ RPM / RPD / TPM / TPD tracked per (platform, model, key)
│
├─ Picks first viable (platform, model, key) tuple
│
├─ Decrypts key in-memory, calls provider SDK
│
└─ On 429 / 5xx / timeout:
Put key on cooldown → retry next model (up to 20 attempts)Rate limit tracking: The router tracks , , , and counters per triple. When a key hits a cap it's cooled down automatically and the next viable key/model is tried.
RPMRPDTPMTPD(platform, model, key)Health checks: Background probes classify each key as , , , or . The router skips non-healthy keys without making a live request.
healthyrate_limitedinvaliderrorDashboard Pages
| Page | Purpose |
|---|---|
| Keys | Add/remove provider credentials, view health status, copy unified API key |
| Fallback Chain | Drag to reorder provider priority |
| Playground | Interactive chat showing which provider served each message + latency |
| Analytics | Request volume, success rate, token counts, latency, per-provider breakdown (24h/7d/30d) |
Production Deployment (Raspberry Pi / Linux)
bash
# Build
npm run build
# Install PM2
npm install -g pm2
# Start
pm2 start server/dist/index.js --name freellmapi
pm2 save
pm2 startup
# nginx reverse proxy (optional)
# /etc/nginx/sites-available/freellmapi
server {
listen 80;
server_name your.domain.com;
location / {
proxy_pass http://localhost:3001;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_set_header Host $host;
proxy_buffering off; # Required for SSE streaming
proxy_cache_control no-cache; # Required for SSE streaming
}
}Memory footprint: ~40 MB RSS at idle on a Pi 4.
Adding a New Provider
Create a new adapter in :
server/src/providers/typescript
// server/src/providers/myprovider.ts
import type { ProviderAdapter, ChatRequest, ChatResponse } from "../types";
export const myProviderAdapter: ProviderAdapter = {
name: "myprovider",
models: ["my-model-v1", "my-model-v2"],
async chat(request: ChatRequest, apiKey: string): Promise<ChatResponse> {
// Call provider API, return OpenAI-shaped response
const res = await fetch("https://api.myprovider.com/v1/chat", {
method: "POST",
headers: {
Authorization: `Bearer ${apiKey}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
model: request.model,
messages: request.messages,
}),
});
const data = await res.json();
return {
id: data.id,
object: "chat.completion",
choices: [{ message: data.choices[0].message, finish_reason: "stop", index: 0 }],
usage: data.usage,
};
},
async *stream(request: ChatRequest, apiKey: string): AsyncGenerator<string> {
// Yield SSE chunks
},
};Register in and add rate limit caps to the router config.
server/src/providers/index.tsTroubleshooting
"No healthy keys available"
- Check the Keys dashboard — all keys may be rate-limited or invalid.
- Wait for cooldown (usually a few minutes for RPM limits) or add more keys.
- Verify the key is valid by testing it directly against the provider's API.
Requests always fall back to the same provider
- Check the Fallback Chain order in the dashboard.
- Ensure keys for higher-priority providers are marked .
healthy
Streaming stops mid-response
- If behind nginx, ensure is set.
proxy_buffering off - Check provider-side token/minute caps — the stream may be cut by a mid-stream rate limit.
ENCRYPTION_KEY- Ensure in
ENCRYPTION_KEYis exactly 64 hex characters (32 bytes)..env - Regenerate:
node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"
Tool calls not working with a specific provider
- Not all free-tier models support function calling. Check the provider's docs.
- Try — the router will pick a tool-capable model.
model="auto" - Gemini tool calls are auto-translated; others pass through as-is.
High latency on first request
- Health checks run periodically in the background. The first request after startup may probe a few keys. Subsequent requests are faster.
Limitations
- Text-only — no vision/multimodal inputs
- No embeddings ()
/v1/embeddings - No image generation ()
/v1/images/* - No audio/speech ()
/v1/audio/* - No legacy completions ()
/v1/completions - No moderation ()
/v1/moderations - not supported (single completion per request)
n > 1 - Single-user by design — no per-user billing or multi-tenant auth
- Personal/experimental use only — review each provider's ToS before production use