Nex N2.5 Pro

by nex-agi · family nex

Facts

Release date	2026-09-08
Retired date	—
Knowledge cutoff	—
Context (max)	262,144
Max output	—
Modalities	text, image → text
Aliases	`nex-n2.5-pro`
Open weights	no
Description	Nex N2.5 Pro succeeds N2 Pro barely three months after it: 262K context, text+image input, reasoning-capable. Currently served only as OpenRouter's :free SKU; weights not yet public.

Unknown values are shown as —.

Offerings

Provider	Wire ID	Variant	Endpoint	Protocol	Status	Price (USD / Mtok)	Reasoning
OpenRouter	`nex-agi/nex-n2.5-pro:free`	pro	chat-completions	openai-chat	ga	0.00 / 0.00	effort · default on · returns reasoning_content · round-trips reasoning_content

Reasoning controls

OpenRouter· nex-agi/nex-n2.5-pro:free· chat-completions effort

reasoning.effort nonelowmedium●highxhighmax

effort · default on · returns reasoning_content · round-trips reasoning_content

Example requests

OpenRouter · openai-chat · nex-agi/nex-n2.5-pro:free

curl 'https://openrouter.ai/api/v1/chat/completions' \
  -H 'Authorization: Bearer <YOUR_API_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "nex-agi/nex-n2.5-pro:free",
  "messages": [
    {
      "role": "user",
      "content": "Tell me about the weather."
    }
  ],
  "reasoning": {
    "effort": "medium"
  }
}'

Python (requests)

import requests

resp = requests.post(
    "https://openrouter.ai/api/v1/chat/completions",
    headers={
      "Authorization": "Bearer <YOUR_API_KEY>",
      "Content-Type": "application/json"
    },
    json={
      "model": "nex-agi/nex-n2.5-pro:free",
      "messages": [
        {
          "role": "user",
          "content": "Tell me about the weather."
        }
      ],
      "reasoning": {
        "effort": "medium"
      }
    },
)
print(resp.json())

TypeScript (fetch)

const resp = await fetch("https://openrouter.ai/api/v1/chat/completions", {
  method: "POST",
  headers: {
    "Authorization": "Bearer <YOUR_API_KEY>",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "model": "nex-agi/nex-n2.5-pro:free",
    "messages": [
      {
        "role": "user",
        "content": "Tell me about the weather."
      }
    ],
    "reasoning": {
      "effort": "medium"
    }
  }),
})
console.log(await resp.json())

⚠ Responses include reasoning_content artifacts — pass them back unmodified on subsequent turns (dropping them triggers 400s or quality loss).