Gemini 3.1 Pro Preview Custom Tools
google/gemini-3.1-pro-preview-customtoolsGemini 3.1 Pro Preview Custom Tools is a separate endpoint of Google's Gemini 3.1 Pro Preview, the Pro-tier reasoning model of the Gemini 3 series, tuned for agentic workflows that mix bash with custom tools. Google says it is better at prioritizing user-defined functions, such as file viewing or code search tools, over a general bash tool. Pick it for coding agents built on custom tools; Google notes quality may fluctuate in use cases that do not benefit from such tools, where the standard 3.1 Pro Preview fits better.
- Input price
- $1.70
$2.00USD / 1M tokens - Output price
- $10.20
$12.00USD / 1M tokens - Cache read
- $0.17
$0.20USD / 1M tokens - Context window
- 1M
- Max output
- 65.5K
Specifications
- Input
- Text, image, audio
- Output
- Text
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OpenAI-compatible endpoint with unified authentication and usage tracking.
# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
-X POST "https://api.sandbase.ai/v1/chat/completions" \
-H "Authorization: Bearer $SANDBASE_API_KEY" \
-H "Content-Type: application/json" \
--data-binary @- <<'SANDBASE_JSON'
{
"model": "google/gemini-3.1-pro-preview-customtools",
"messages": [
{
"role": "user",
"content": "Hello"
}
],
"max_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"Questions
FAQ
How do I call Google Gemini 3.1 Pro Preview Custom Tools through SandBase?
Create a SandBase API key, then send requests with the model ID "google/gemini-3.1-pro-preview-customtools" to Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.
How much does Google Gemini 3.1 Pro Preview Custom Tools cost?
$1.70 per 1M input tokens and $10.20 per 1M output tokens with the current 15% discount (list price $2 / $12), billed per request from your SandBase balance.
What is the context window of Google Gemini 3.1 Pro Preview Custom Tools?
1M tokens of context, with up to 65.5K output tokens per response.
Which features does Google Gemini 3.1 Pro Preview Custom Tools support?
Google Gemini 3.1 Pro Preview Custom Tools supports vision (image input), reasoning, function calling, structured output. See Specifications above for the full list.
Do I need a separate Google account?
No. One SandBase API key and balance gives you access to Google Gemini 3.1 Pro Preview Custom Tools and the other models in the catalog; you do not need to sign up with Google separately.