Chat Completions

Use POST /v1/chat/completions when your application already sends ordered message arrays and reads choices[0].message.

On this page 1 of 6

Request#

A minimal request includes a public model and at least one message:

Send a Chat Completions request

from getpass import getpass

from openai import OpenAI

client = OpenAI(
    base_url="https://api.keirolabs.ai/v1",
    api_key=getpass("Keiro API key: "),
)

response = client.chat.completions.create(
    model="eb1-preview",
    messages=[
        {"role": "system", "content": "Answer concisely."},
        {"role": "user", "content": "Explain vector databases."},
    ],
)

print(response.choices[0].message.content)

Send a Chat Completions request

import fs from "node:fs";
import OpenAI from "openai";

const keyPath = process.env.KEIRO_KEY_FILE;
if (!keyPath) {
  throw new Error("KEIRO_KEY_FILE must point to a protected secret file");
}

const client = new OpenAI({
  baseURL: "https://api.keirolabs.ai/v1",
  apiKey: fs.readFileSync(keyPath, "utf8").trim(),
});

const response = await client.chat.completions.create({
  model: "eb1-preview",
  messages: [
    { role: "system", content: "Answer concisely." },
    { role: "user", content: "Explain vector databases." },
  ],
});

console.log(response.choices[0].message.content);

Send a Chat Completions request

printf 'Keiro API key: '
IFS= read -rs KEIRO_BEARER
printf '\n'

curl -sS https://api.keirolabs.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "eb1-preview",
    "messages": [
      {"role": "system", "content": "Answer concisely."},
      {"role": "user", "content": "Explain vector databases."}
    ]
  }' \
  -H @- <<<"Authorization: Bearer $KEIRO_BEARER"

JSON payload JSON

{
  "model": "eb1-preview",
  "messages": [
    {
      "role": "user",
      "content": "Explain token buckets in one sentence."
    }
  ]
}

Use the system role or supported top-level system compatibility field for stable instructions. Keep application-specific context in explicit messages.

Response#

Read generated text from choices[0].message.content, the terminal reason from choices[0].finish_reason, and canonical token accounting from usage.

Treat the public response layout as the contract. Do not depend on private model selection, vendor metadata, or internal cost fields.

Supported controls#

The current Chat Completions surface supports the documented message input plus controls including stream, temperature, top_p, stop, max_tokens or max_completion_tokens, seed, tools, tool_choice, parallel_tool_calls, text response format, logprobs, user, metadata, and reasoning controls.

Strict validation rejects unknown fields. JSON mode and JSON Schema structured output are not currently supported.

Streaming#

Set stream to true to receive server-sent events. Text arrives in choices[0].delta.content; tool calls arrive in delta.tool_calls. Assemble fragments by choice and tool-call index, and wait for the terminal finish reason before executing a tool.

Stream a Chat Completions request

from getpass import getpass

from openai import OpenAI

client = OpenAI(
    base_url="https://api.keirolabs.ai/v1",
    api_key=getpass("Keiro API key: "),
)

stream = client.chat.completions.create(
    model="eb1-preview",
    messages=[{"role": "user", "content": "Count to three."}],
    stream=True,
)

for chunk in stream:
    delta = chunk.choices[0].delta.content
    if delta:
        print(delta, end="", flush=True)

Stream a Chat Completions request

import fs from "node:fs";
import OpenAI from "openai";

const keyPath = process.env.KEIRO_KEY_FILE;
if (!keyPath) {
  throw new Error("KEIRO_KEY_FILE must point to a protected secret file");
}

const client = new OpenAI({
  baseURL: "https://api.keirolabs.ai/v1",
  apiKey: fs.readFileSync(keyPath, "utf8").trim(),
});

const stream = await client.chat.completions.create({
  model: "eb1-preview",
  messages: [{ role: "user", content: "Count to three." }],
  stream: true,
});

for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}

Stream a Chat Completions request

printf 'Keiro API key: '
IFS= read -rs KEIRO_BEARER
printf '\n'

curl -sS -N https://api.keirolabs.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "eb1-preview",
    "stream": true,
    "messages": [
      {"role": "user", "content": "Count to three."}
    ]
  }' \
  -H @- <<<"Authorization: Bearer $KEIRO_BEARER"

Streams are governed by documented idle and wall-clock time entitlements, not a flat timeout. reasoning_effort selects the run's entitlement row — see Streaming, and the same page for terminal and error handling.

Tools and images#

Function tools use the Chat Completions nested tools[].function shape and return message.tool_calls; see Tool calling.
Images use image_url content parts inside a user message; see Images and vision.

Chat Completions

Request#

Response#

Supported controls#

Streaming#

Tools and images#

Related pages#