Cheapest LLM API? $0.80 in, $3.20 out.

Keep your SDK

Change the base URL, key and model string.

The API speaks the OpenAI Chat Completions and Anthropic Messages formats (API spec). Keep the SDK you already use. These are the quickstart examples:

OpenAI-format SDK (Python)

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.unbiased.ai/v1",
    api_key=os.environ["UNBIASED_API_KEY"],
)
reply = client.chat.completions.create(
    model="pareto",
    messages=[{"role": "user", "content": "Hello"}],
)
print(reply.choices[0].message.content)

Anthropic-format SDK (Python)

import os
import anthropic

client = anthropic.Anthropic(
    base_url="https://api.unbiased.ai",
    api_key=os.environ["UNBIASED_API_KEY"],
)
message = client.messages.create(
    model="pareto",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello"}],
)
print(message.content[0].text)

Model listing (GET /v1/models) isn’t implemented yet, so set the model string pareto yourself. Validate your client’s streaming, tools and error handling before you move live traffic.

One real call

A real bug fix for under a cent.

The problem: a small Python helper should split a list into groups of a set size, but it drops the last group. Asked to split [1, 2, 3, 4, 5] into pairs, it returns [[1, 2], [3, 4]] and loses the 5. We gave Pareto the function and the failing check, applied its fix and reran the checks.

def chunk(items, size):
    """Split items into lists of at most `size` elements."""
    out = []
    for i in range(0, len(items) - size, size):
        out.append(items[i:i + size])
    return out

assert chunk([1, 2, 3, 4, 5], 2) == [[1, 2], [3, 4], [5]]

def chunk(items, size):
    """Split items into lists of at most `size` elements."""
    out = []
    for i in range(0, len(items), size):
        out.append(items[i:i + size])
    return out

The change, in plain words

The loop stopped before the end of the list, so the last group was never added. Pareto changed one line so the loop runs to the end.

for i in range(0, len(items) - size, size):

for i in range(0, len(items), size):

from chunk import chunk

assert chunk([1, 2, 3, 4], 2) == [[1, 2], [3, 4]]
assert chunk([1, 2, 3, 4, 5], 2) == [[1, 2], [3, 4], [5]]
assert chunk([1], 3) == [[1]]
print("3 checks passed")

$ python3 test_chunk.py   # before the fix
AssertionError
$ python3 test_chunk.py   # after the fix
3 checks passed

Captured October 17, 2026 from the Unbiased API (model pareto, served as Pareto 26.10). 702 tokens (132 prompt, 570 answer). The original function fails the first check too: it also drops the second pair of an even split. Raw capture and checks.