xAI: Grok Build 0.1

x-ai/grok-build-0.1

Grok Build 0.1 is xAI’s fast coding model trained specifically for agentic software engineering workflows. It supports text and image inputs with text output, and is optimized for interactive coding a...

visiontools
MODALITIES
INPUT PRICE
$1per 1M
OUTPUT PRICE
$2per 1M
CONTEXT
256K
RELEASED
May 21, 2026
ProviderCacheUptimeChat
$1$2
Cache read$0.2

Capabilities

Input modalities
fileimagetext
Output modalities
text
Features
frequency_penaltyinclude_reasoninglogprobsmax_tokenspresence_penaltyreasoningresponse_formatseedstopstructured_outputstemperaturetool_choicetoolstop_logprobstop_p
1

Get your API key

Create an API key from the Keys page, then set it as an environment variable:

export ONLIST_API_KEY=sk-...
2

Make your first request

Endpoints

POSThttps://onlist.io/v1/chat/completions

OpenAI Chat Completions format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:x-ai/grok-build-0.1
POSThttps://onlist.io/v1/responses

OpenAI Responses format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:x-ai/grok-build-0.1
POSThttps://onlist.io/v1/messages

Anthropic Messages format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:x-ai/grok-build-0.1

Code samples

curl https://onlist.io/v1/chat/completions \
  -H "Authorization: Bearer $ONLIST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "model": "x-ai/grok-build-0.1",
       "messages": [
         {
           "role": "user",
           "content": "Explain quantum entanglement in one paragraph."
         }
       ]
     }'

Replace $ONLIST_API_KEY with the API key from your Keys page.

Authentication

All requests must include an Authorization: Bearer <TOKEN> header. Generate keys from the Keys page; keys can be scoped to specific models, groups, IP ranges, and rate limits.

3

Enable streaming

Add "stream": true to receive partial responses as server-sent events in real time.

Streaming example

curl https://onlist.io/v1/chat/completions \
  -H "Authorization: Bearer $ONLIST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "model": "x-ai/grok-build-0.1",
       "messages": [
         {
           "role": "user",
           "content": "Write a haiku about recursion."
         }
       ],
       "stream": true
     }'

Supported parameters

NameTypeDescription
frequency_penaltynumberPenalizes new tokens based on their existing frequency in the text (-2.0 to 2.0).
include_reasoning
logprobsbooleanWhether to return log probabilities of the output tokens.
max_tokensintegerMaximum number of tokens to generate in the completion.
presence_penaltynumberPenalizes new tokens based on whether they appear in the text so far (-2.0 to 2.0).
reasoning
response_formatobjectSpecifies the output format. Use {"type": "json_object"} for JSON mode.
seedintegerIf specified, the system will attempt deterministic sampling for reproducible results.
stopstring | arrayUp to 4 sequences where the API will stop generating tokens.
structured_outputs
temperaturenumberSampling temperature between 0 and 2. Higher values make output more random.
tool_choicestring | objectControls which tool is called. "auto", "none", "required", or a specific function.
toolsarrayA list of tools the model may call. Currently supports functions.
top_logprobsintegerNumber of most likely tokens to return at each position (0-20). Requires logprobs: true.
top_pnumberNucleus sampling. The model considers tokens with top_p probability mass.

These are the request parameters this model accepts. Parameter semantics follow the OpenAI Chat Completions specification.