Text model

Aion 3.5

Name: Aion 3.5
Brand: Aion Labs
SKU: aion-labs/aion-3.5

aion-labs/aion-3.5

aion-labs/aion-3.5 is a language model from Aion Labs you can call on the OceanToken API, with a 262K-token context window and up to 33K output tokens; it supports reasoning, tool calling.

Price card, similar models and questions answered: Aion 3.5 on oceantoken.ai.

At a glance

Model ID	`aion-labs/aion-3.5`
Type	Text
Publisher	Aion Labs
Context window	262,144 tokens
Max output	32,768 tokens
Price	On oceantoken.ai
Capabilities	reasoning, tool calling
Endpoint	`/v1/chat/completions, /v1/responses`
API shape	OpenAI-compatible
In the catalog since	2026-09-23

API

POST /v1/chat/completions (also /v1/responses and /v1/messages). Base URL https://api.oceantoken.ai, your OceanToken key as the bearer token. The OpenAI SDKs work unchanged; see the Quickstart.

Download this spec (JSON) · llms.txt for AI assistants

Basic

curl
Python
JavaScript

curl https://api.oceantoken.ai/v1/chat/completions \
  -H "Authorization: Bearer $OCEANTOKEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "aion-labs/aion-3.5",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
from openai import OpenAI

client = OpenAI(base_url="https://api.oceantoken.ai/v1", api_key=os.environ["OCEANTOKEN_API_KEY"])
response = client.chat.completions.create(
    model="aion-labs/aion-3.5",
    messages=[
        {
            "role": "user",
            "content": "Write a haiku about the ocean.",
        },
    ],
)
print(response.choices[0].message.content)

import OpenAI from 'openai';

const client = new OpenAI({baseURL: 'https://api.oceantoken.ai/v1', apiKey: process.env.OCEANTOKEN_API_KEY});
const response = await client.chat.completions.create({
  "model": "aion-labs/aion-3.5",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
});
console.log(response.choices[0].message.content);

Request parameters

Only what this model takes. Anything else in the request is left out before it reaches the model.

Parameter	Type	Description
`model` required	string	This model's ID.
`messages` required	array	The conversation so far: objects with a `role` (`system`, `user`, `assistant` or `tool`) and a `content`, a string or a list of content parts: text, and images, video, audio or files on models that take them.
`stream`	boolean default `false`	Send the answer as server-sent events as it is written.
`stream_options`	object	With `stream`: `{"include_usage": true}` adds a last event with the token counts.
`max_tokens`	integer 1 to 32768	The most tokens to write, reasoning included. `max_completion_tokens` is accepted as the same thing.
`temperature`	number 0 to 2	Randomness: lower is more focused, higher more varied.
`top_p`	number 0 to 1	Nucleus sampling: only the most likely tokens whose probabilities add up to this are considered.
`response_format`	object json_object, json_schema	`{"type": "json_object"}` for JSON output, or `{"type": "json_schema", "json_schema": {"name": ..., "schema": {...}}}` for output that matches your schema.
`tools`	array	Functions the model may call: `{"type": "function", "function": {"name", "description", "parameters"}}`.
`tool_choice`	string or object	`auto` (default), `none`, `required`, or `{"type": "function", "function": {"name": ...}}`.
`parallel_tool_calls`	boolean	`false` asks for at most one tool call per turn.
`reasoning_effort`	string low, high, max default `"high"`	How much the model thinks before answering. This model always reasons; the level sets how much: `low` less reasoning, faster; `high` more reasoning, slower; `max` the most reasoning.
`user`	string	Your own ID for the end user, for your records.

Response

Field	Type	Description
`id`	string	The request's ID.
`choices[].message.content`	string	The answer.
`choices[].message.reasoning_content`	string	The model's reasoning, on models that return it.
`choices[].message.tool_calls`	array	The tools the model wants called, with JSON arguments.
`choices[].finish_reason`	string	`stop`, `length` (hit max_tokens), `tool_calls` or `content_filter`.
`usage.prompt_tokens`	integer	Input tokens, media included.
`usage.completion_tokens`	integer	Output tokens, reasoning included.
`usage.prompt_tokens_details.cached_tokens`	integer	Input tokens read from the prompt cache.
`usage.completion_tokens_details.reasoning_tokens`	integer	Output tokens spent reasoning.

With stream: true, chat.completion.chunk events carry choices[].delta; the stream ends with data: [DONE].

Example response

{
  "id": "chatcmpl-...",
  "object": "chat.completion",
  "created": 1792000000,
  "model": "aion-labs/aion-3.5",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "...",
        "reasoning_content": null,
        "tool_calls": null
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 12,
    "completion_tokens": 20,
    "total_tokens": 32,
    "prompt_tokens_details": {
      "cached_tokens": 0
    },
    "completion_tokens_details": {
      "reasoning_tokens": 0
    }
  }
}

More examples and how errors and billing work: Text generation.

Compared with similar models

Text models on OceanToken in the same price range as aion-labs/aion-3.5. Compare their prices on oceantoken.ai.

Model	Publisher	Context
Aion 3.5 `aion-labs/aion-3.5`	Aion Labs	262,144
Mistral Large `mistralai/mistral-large`	Mistral AI	128K
Mistral Large 2407 `mistralai/mistral-large-2407`	Mistral AI	131K
Mixtral 8x22b Instruct `mistralai/mixtral-8x22b-instruct`	Mistral AI	66K

Use it

Create an account Price on oceantoken.ai

The facts on this page were read from the live OceanToken catalog on 2026-11-05 (UTC), when the documentation was built. Prices are published on oceantoken.ai.