gpt-6.1-sol — API, Pricing & Context Window | Vivgrid

gpt-6.1-sol is the latest balanced model in OpenAI's gpt-6 family, succeeding gpt-6-sol. It keeps the generation's 1.05M-token context window and 128K-token max output at the same per-token price as gpt-6-sol, making it the new default for production coding agents that need more than a small model.

On Vivgrid, gpt-6.1-sol is served through a single OpenAI-compatible endpoint with geo-distributed acceleration across AMER, EMEA, and APAC, so requests are routed to the nearest compute region for lower latency. Moving an agent from gpt-6-sol is a model-string change in the Console, with no application code to touch.

It is available on both OpenAI surfaces — Chat Completions (/chat/completions) and the Responses API (/responses) — so coding CLIs that expect the Responses wire format, such as Codex and Pi, work against the same key.

Specifications

Pricing

Pricing in USD per 1M tokens.

What one request costs

The rates above applied to a 20K-token prompt with a 2K-token reply — a typical single agent turn, small enough that every request is billed at the base rate.

Prompt caching is billed at $2.50 per 1M cache-write tokens, with cached reads at $0.20.

Requests beyond 272K input tokens are billed at the long-context rate: $4.00 input / $0.40 cached input / $5.00 cache write / $15.00 output per 1M tokens.

Use gpt-6.1-sol in your coding agent

gpt-6.1-sol works with the same Vivgrid key and https://api.vivgrid.com/v1 endpoint as every other model in the catalog. Grab your API key from the Vivgrid Console, then drop one of the configurations below into your agent of choice.

Codex

Install Codex:

npm i -g @openai/codex

Add Vivgrid as a provider and make gpt-6.1-sol the default model in ~/.codex/config.toml. Codex talks to Vivgrid over the Responses API:

model = "gpt-6.1-sol"
model_provider = "vivgrid"
preferred_auth_method = "apikey"
forced_login_method = "api"

[features]
streamable_shell = true
unified_exec = true
shell_snapshot = true

[model_providers.vivgrid]
name = "Vivgrid"
base_url = "https://api.vivgrid.com/v1"
wire_api = "responses"
experimental_bearer_token = "viv-xxxxxxxxxxxxx"

Then start Codex in your project:

codex

Already using another Vivgrid model in Codex? Switch for a single run with codex -m gpt-6.1-sol. See the full Codex tutorial.

OpenCode

OpenCode has Vivgrid built in, so you can use gpt-6.1-sol without writing any config: open /models, search for vivgrid, paste your API key and pick the model. The OpenCode tutorial walks through it step by step.

Prefer to configure it by hand? Install OpenCode:

npm i -g opencode-ai

Declare gpt-6.1-sol under the Vivgrid provider in your global OpenCode config, ~/.config/opencode/opencode.json. The @ai-sdk/openai provider talks to Vivgrid over the Responses API (/v1/responses):

{
  "$schema": "https://opencode.ai/config.json",
  "model": "vivgrid/gpt-6.1-sol",
  "provider": {
    "vivgrid": {
      "npm": "@ai-sdk/openai",
      "name": "Vivgrid",
      "options": {
        "baseURL": "https://api.vivgrid.com/v1",
        "apiKey": "{env:VIVGRID_API_KEY}"
      },
      "models": {
        "gpt-6.1-sol": {
          "name": "gpt-6.1-sol",
          "tool_call": true,
          "attachment": true,
          "modalities": { "input": ["text", "image"], "output": ["text"] },
          "limit": { "context": 1050000, "output": 128000 }
        }
      }
    }
  }
}

Export your key and launch OpenCode:

export VIVGRID_API_KEY="viv-xxxxxxxxxxxxx"
opencode

Use /models to switch between gpt-6.1-sol and other Vivgrid models mid-session. See the full OpenCode tutorial.

Pi

Install Pi:

npm install -g --ignore-scripts @earendil-works/pi-coding-agent

Add gpt-6.1-sol to the Vivgrid provider in ~/.pi/agent/models.json. The provider defaults to Chat Completions, and gpt-6.1-sol overrides api at the model level to use the Responses API (/v1/responses):

{
  "providers": {
    "vivgrid": {
      "baseUrl": "https://api.vivgrid.com/v1",
      "apiKey": "viv-xxxxxxxxxxxxx",
      "api": "openai-completions",
      "compat": {
        "sendSessionAffinityHeaders": true
      },
      "models": [
        {
          "id": "gpt-6.1-sol",
          "api": "openai-responses",
          "input": ["text", "image"],
          "contextWindow": 1050000,
          "maxTokens": 128000
        }
      ]
    }
  }
}

Make it the model Pi starts with in ~/.pi/agent/settings.json:

{
  "defaultProvider": "vivgrid",
  "defaultModel": "gpt-6.1-sol"
}

Then verify and start Pi:

pi --list-models vivgrid
pi

Or run a one-shot prompt without entering the TUI:

pi -p "explain the auth flow in this repo" --model vivgrid/gpt-6.1-sol

See the full Pi tutorial.

API surfaces

The Vivgrid Console catalogs gpt-6.1-sol on 2 surfaces, all behind the same API key. The endpoint shown is the one the Console previews for that surface.

Quick start

Get an API key from the Vivgrid Console, then call gpt-6.1-sol directly.

curl https://api.vivgrid.com/v1/chat/completions \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-6.1-sol",
    "messages": [
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }
    ],
    "stream": true
  }'

curl https://api.vivgrid.com/v1/responses \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-6.1-sol",
    "input": "Refactor this function and explain the change.",
    "stream": true
  }'

Choosing within the gpt-6 family

Prices are USD per 1M tokens at the base rate. Rows marked this page are the model described here.

Ideal use cases

• Production coding agents balancing quality, speed, and cost
• Coding CLIs on the Responses API (Codex, Pi, OpenCode)
• Whole-repository analysis within a 1.05M-token context
• Teams on gpt-6-sol upgrading at the same price

Related models

• gpt-6-sol — the prior balanced gpt-6 release
• gpt-6-astra — the gpt-6 generation flagship
• gpt-6-luna — the fast, low-cost gpt-6 model