Aion-2.0 API

Aion-2.0 on AIMLAPI.

Modalities
Image, TextText
In / Out price
$0.8464/$1.69per 1M
Context window
128K tokens
Released
Feb 23, 2026

Aion-2.0 overview

The pelican test: one prompt, every text model, unedited SVG output from Nov 3, 2026.

SVG of a pelican riding a bicycle, written by Aion-2.0 through AI/ML API

Aion-2.0 specs

Model ID
aion-labs/aion-2.0
Developer
AionLabs
Context window
131,072 tokens
Max output
32,768 tokens
Input
Image, Text
Output
Text
API
OpenAI-compatible, base URL https://api.aimlapi.com/v1

Coding and code review
Generate, debug, and review code across languages, reading whole files or repos in a single prompt.

Agentic and multi-step workflows
Reliable tool-calling and instruction-following suit agent loops that plan, call tools, and iterate.

Complex reasoning
Extended reasoning improves reliability on multi-step math, logic, and technical analysis.

Long-document analysis
Summarize and extract from contracts, papers, and reports without aggressive chunking.

Use cases

Aion-2.0 is documented as suited for immersive roleplaying and storytelling. It is also described as a strong choice for interactive fiction, character-driven chat experiences, and creative writing tools where narrative depth and engagement matter more than raw speed.

It is also suited to introducing tension, crises, and conflict into stories, making narratives feel more engaging. In addition, it handles mature and darker themes with more nuance and depth.

It is described as fitting creative writing and roleplaying workflows. It is also presented as useful for chat experiences centered on characters and narrative interaction.

Capabilities

  • Function calling
  • Reasoning
  • Streaming
  • Structured outputs
  • Web search

Aion-2.0 API pricing

Aion-2.0 pricing in US dollars
UsagePriceUnit
Input$0.84641M tokens
Output$1.691M tokens
Cached input$0.21161M tokens

Prices from the AI/ML API price list, checked on Nov 4, 2026.

Aion-2.0 vs other models: token prices

AI/ML API input and output rates for 5 models, per million tokens.

AI/ML API model prices in USD per million tokens
ModelInputOutput
Aion-2.0$0.8464$1.69
Aion-3.5-Mini$0.7406$1.48
Aion-3.0-Mini$0.7406$1.48
Aion-3.5$3.17$6.35
Aion-3.0$3.17$6.35

How to use the Aion-2.0 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "aion-labs/aion-2.0",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

Related articles

All posts

Aion-2.0 FAQ

What is the context window of Aion-2.0?

Aion-2.0 has a 131,072 tokens context window and can return up to 32,768 tokens.

What inputs and outputs does Aion-2.0 support?

Aion-2.0 takes image, text as input and returns text.

What is the model ID for Aion-2.0?

Use aion-labs/aion-2.0 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

How much does Aion-2.0 cost?

Aion-2.0 costs $0.8464 input and $1.69 output per 1M tokens on AI/ML API, billed as you go with no subscription.

Does Aion-2.0 support streaming?

Yes, Aion-2.0 can stream responses as they are generated.

Can Aion-2.0 read images?

Yes, Aion-2.0 accepts image input alongside text.

Start building with Aion-2.0

Aion-2.0 API

aion-labs/aion-2.0

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "aion-labs/aion-2.0",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'