MiniMax M3 API
AvailableMiniMax M3 is an open-weight reasoning model from MiniMax with a 512K-token context window. It passed our tool-calling and JSON-schema tests and completed a multi-step Codex CLI task through the Responses API on this endpoint. It runs on serverless GPUs in the United States.
Quickstart
Set INFERENCE_API_KEY to your key from the API Keys page, then run:
curl https://api.inferenceapis.com/v1/chat/completions \
-H "Authorization: Bearer $INFERENCE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "MiniMaxAI/MiniMax-M3",
"messages": [
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hello! What can you do?"}
]
}'
import os
from openai import OpenAI
client = OpenAI(
base_url="https://api.inferenceapis.com/v1",
api_key=os.environ["INFERENCE_API_KEY"],
)
response = client.chat.completions.create(
model="MiniMaxAI/MiniMax-M3",
messages=[
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hello! What can you do?"},
],
)
print(response.choices[0].message.content)
import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.inferenceapis.com/v1",
apiKey: process.env.INFERENCE_API_KEY,
});
const response = await client.chat.completions.create({
model: "MiniMaxAI/MiniMax-M3",
messages: [
{ role: "system", content: "You are a helpful assistant." },
{ role: "user", content: "Hello! What can you do?" },
],
});
console.log(response.choices[0].message.content);
When to use it
- You want a large-context agent model priced near the Flash tier
- Nothing specific; compare on your own prompts.
What it costs in practice
| Workload | Cost |
|---|---|
| Chat assistant — 10,000 turns of 800 tokens in, 300 out | $7.80 |
| Long prompts or RAG — 10,000 requests of 8,000 in, 500 out | $39.00 |
| Generation-heavy — 10,000 requests of 500 in, 2,000 out | $33.15 |
Computed from the live rates below. This is a reasoning model, and thinking is billed as output, so real output counts run above the visible answer; see controlling reasoning to keep that down. There is no subscription or minimum; new accounts start with free credit.
Endpoint
Content-Type: application/json
/openai/v1/… is accepted too, so Groq-style base URLs work with only the host changed.
Model IDs and aliases
Send any of these as model; they all resolve to this model and bill at its rate.
| ID | Note |
|---|---|
MiniMaxAI/MiniMax-M3 | Canonical |
minimax-m3 | Alias |
Request body
| Parameter | Type | Description |
|---|---|---|
model required |
string | Model ID: MiniMaxAI/MiniMax-M3 — also accepted: minimax-m3 |
messages required |
array | Conversation so far. Each item has a role (system, user or assistant) and content. |
max_tokens |
integer | Maximum number of tokens to generate (includes reasoning tokens — use a few hundred or more). |
temperature |
number | Sampling temperature. Higher values give more varied output. |
top_p |
number | Nucleus sampling cutoff. |
stream |
boolean | Stream the response as server-sent events. The final chunk includes usage. |
tools |
array | Tool definitions for function calling (OpenAI format). |
response_format |
object | {"type": "json_object"} for JSON mode. |
stop |
string | array | Sequences where the model stops generating. |
seed |
integer | Seed for more reproducible sampling. |
Response
{
"id": "chatcmpl-abc123",
"object": "chat.completion",
"model": "MiniMaxAI/MiniMax-M3",
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "Hi! I can answer questions, write and edit text, help with code and more.",
"reasoning": "The user is greeting me and asking about capabilities..."
},
"finish_reason": "stop"
}
],
"usage": { "prompt_tokens": 28, "completion_tokens": 17, "total_tokens": 45 }
}
Controlling reasoning
Send reasoning_effort: "none" to switch thinking off. On our test question this model used 22 completion tokens by default and 27 with thinking off, and the answer started immediately instead of after the reasoning. Model families disagree on the parameter for this, and the wrong one is silently ignored, so the gateway accepts one spelling on every model (also "minimal", reasoning: {"enabled": false} and thinking: {"type": "disabled"}) and sends the switch this model honours; the X-Thinking: off response header confirms it. On the Responses API use reasoning: {"effort": "minimal"}. Leave thinking on for multi-step coding and maths; turn it off for extraction, classification, routing and chat. All models compared.
resp = client.chat.completions.create(
model="MiniMaxAI/MiniMax-M3",
reasoning_effort="none", # thinking off; omit it to let the model reason
messages=[{"role": "user", "content": "Extract the invoice number from: ..."}],
max_tokens=500,
)
print(resp.choices[0].message.content)Token counts are single measurements from September 17, 2026 and vary with the question; the direction is what matters.
Tested on this endpoint
Tool calling (tools, tool_calls) | Works |
JSON mode (response_format: json_object) | Works |
Schema-constrained output (response_format: json_schema) | Works |
Streaming with usage in the final chunk | Works |
| System prompt followed | Works |
Reasoning tokens reported in usage | Works |
Each row is a live request we sent on September 17, 2026, not a claim copied from a model card. Streamed and parallel tool calls and tool_choice were tested too: full matrix for every model. Request examples are in the API documentation.
Pricing
| Input | $0.39 / 1M tokens |
| Cached input | $0.08 / 1M tokens |
| Output | $1.56 / 1M tokens |
| Billing | Pay as you go from prepaid credits. No subscription, no daily request or token cap. See all pricing. |
Notes
- Reasoning model: set
max_tokensgenerously and stream if a person is waiting. - The thinking is returned in
reasoning_contentand billed as completion tokens.
Compare MiniMax M3 with…
Errors
Errors use the OpenAI envelope: {"error": {"message", "type", "code"}}. 401 missing or invalid key · 402 insufficient_balance · 404 model_not_found · 503 model_unavailable · 502 backend error, safe to retry. Full table with what to retry: API documentation. Errors from other providers: provider error reference.
