API compatibility - 8 documented limits
MiniMax API compatibility
MiniMax documents an OpenAI-compatible API at https://api.minimax.io/v1 (chat/completions, responses and models). Its Anthropic-compatible base URL, the value for ANTHROPIC_BASE_URL, is https://api.minimax.io/anthropic. The docs list 8 limitations: 6 for the OpenAI-compatible layer and 2 for the Anthropic-compatible layer.
Verified against MiniMax's own documentation. Not documented means the docs read that day do not say; it never means No.
Compare every provider in the API compatibility matrix.
OpenAI-compatible API
Supportedhttps://api.minimax.io/v1- Endpoints
- chat/completions
- responses
- models
- Auth
- Authorization: Bearer <API key> (docs set OPENAI_API_KEY for the SDK)
- Notes
- International platform (platform.minimax.io). Responses API is documented as POST /v1/responses on https://api.minimax.io. MiniMax-M3.1-Flash-Preview is available only through M Plan and MiniMax Code for now. Thinking content returned in reasoning_content (M3.1-Flash-Preview) or inside <think> tags in content (other models).
From the docs
To meet developers' needs for the OpenAI API ecosystem, our API now supports the OpenAI API format. ... export OPENAI_BASE_URL=https://api.minimax.io/v1
Anthropic-compatible API
Supportedhttps://api.minimax.io/anthropic- Auth
- ANTHROPIC_API_KEY env var for the SDK; curl example uses Authorization: Bearer <MINIMAX_API_KEY>
- Notes
- Only MiniMax-M3.1-Flash-Preview, M3, M2.7(-highspeed), M2.5(-highspeed), M2.1(-highspeed) and M2 are supported on this interface. Also supports POST /anthropic/v1/messages/count_tokens for M3.1-Flash-Preview and M3.
From the docs
export ANTHROPIC_BASE_URL=https://api.minimax.io/anthropic export ANTHROPIC_API_KEY=${YOUR_API_KEY}
Documented limitations
Parameters, content types and features MiniMax's docs say its compatibility layers ignore, reject or change, each with the line it comes from. A layer with nothing listed may still differ in ways the docs do not spell out.
OpenAI-compatible layer6
presence_penalty, frequency_penalty, logit_bias ignored
Some OpenAI parameters (such as
presence_penalty,frequency_penalty,logit_bias, etc.) will be ignoredplatform.minimax.io/docs/api-reference/text-openai-api.md n only supports 1
The
nparameter only supports value 1platform.minimax.io/docs/api-reference/text-openai-api.md deprecated function_call not supported
The deprecated
function_callis not supported, please use thetoolsparameterplatform.minimax.io/docs/api-reference/text-openai-api.md audio input not supported
audio input is not currently supported
platform.minimax.io/docs/api-reference/text-openai-api.md temperature must be in [0, 2]
The
temperatureparameter range is [0, 2], recommended value: 1.0, values outside this range will return an errorplatform.minimax.io/docs/api-reference/text-openai-api.md reasoning_effort none not supported
noneis not supported and returns400.platform.minimax.io/docs/api-reference/text-openai-api.md
Anthropic-compatible layer2
top_k, stop_sequences, mcp_servers, context_management, container ignored
Some Anthropic parameters (such as
top_k,stop_sequences,mcp_servers,context_management,container) will be ignoredplatform.minimax.io/docs/api-reference/text-anthropic-api.md M2.x models: text and tool-call blocks only, no image/video
The M2.7, M2.5, M2.1, and M2 series support text and tool-call content blocks only
platform.minimax.io/docs/api-reference/text-anthropic-api.md
Example from MiniMax's docs
Copied verbatim from the provider's documentation, placeholders included.
export OPENAI_BASE_URL=https://api.minimax.io/v1
export OPENAI_API_KEY=${YOUR_API_KEY}
from openai import OpenAI
client = OpenAI()
response = client.chat.completions.create(
model="MiniMax-M3.1-Flash-Preview",
reasoning_effort="max",
messages=[
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hi, how are you?"},
],
)More on MiniMax
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