GPT-5.6 Sol
TL;DR
PremiumOpenAI's frontier model for complex professional work.
Available on
Not on the Go plan ($1/mo, open-source models only).
Switch with
Pick GPT-5.6 Sol from the selector.
Input
$5
per M tokens
Output
$30
per M tokens
Cache read
$0.50
per M tokens
GPT-5.6 Sol in Command Code
GPT-5.6 Sol is OpenAI's frontier model, tuned for complex professional work where reasoning quality is the dominant factor. Reach for it when the task is ambiguous, high-stakes, or needs a long agentic run to get right.
Sol vs the Command Code lineup
Pricing for Sol alongside its closest relatives. Quality numbers shown where benchmarked.
| Model | Intelligence | Speed | Input $/M | Output $/M |
|---|---|---|---|---|
| GPT-5.6 Sol | Not yet scored | — | $5.00 | $30.00 |
| GPT-5.5 | 60 | ~65 tok/s | $5.00 | $30.00 |
| Claude Opus 4.7 | 57 | ~49 tok/s | $5.00 | $25.00 |
| GPT-5.4 | 57 | ~84 tok/s | $2.50 | $15.00 |
What GPT-5.6 Sol is best for
The hardest reasoning work, ambiguous specs, multi-step agent runs that depend on getting each step exactly right, and senior code review on critical changes.
When to switch away from GPT-5.6 Sol
Switch to GPT-5.6 Terra
For everyday work that balances intelligence and cost, at half the input price ($2.50 vs $5).
Switch to GPT-5.6 Luna
For cost-sensitive, high-volume work ($1 vs $5 input).
Switch to Claude Opus 4.7
For the Claude family on the hardest work, at a cheaper output price ($25 vs $30 / M).
In Command Code: caching and taste-1
Two things change the experience of using this model inside Command Code versus calling it directly through the upstream API.
First, prompt caching is on by default. In an agent loop the same context is read across many steps; cache reads are billed at $0.50 per million tokens versus $5 for fresh input.
Second, taste-1 sits between the model and the agent loop, rewriting and reranking candidate edits to match your codebase conventions.
Plan availability
Premium model. Available on Pro ($15/mo), Max 10× ($100/mo), Max 20× ($200/mo), Teams ($40/mo per seat), and Enterprise. Not on the Go plan.
All Command Code models, ranked by quality and speed
Quality is the Intelligence Index — an aggregate score across reasoning, math, coding, and knowledge evaluations. Speed is reported output tokens per second. Models without a published score are noted.
| Model | Tier | Intelligence Index | Output speed |
|---|---|---|---|
| GPT-5.5 | Premium | 60 | ~65 tok/s |
| Claude Opus 4.7 | Premium | 57 | ~49 tok/s |
| GPT-5.4 | Premium | 57 | ~84 tok/s |
| GPT-5.3 Codex | Premium | 54 | ~72 tok/s |
| Kimi K2.6 | Open-source | 54 | ~40 tok/s |
| Claude Sonnet 4.6 | Premium | 52 | ~62 tok/s |
| DeepSeek V4 Pro | Open-source | 52 | ~35 tok/s |
| GLM-5 | Open-source | 50 | ~61 tok/s |
| GPT-5.4 Mini | Premium | 49 | ~164 tok/s |
| DeepSeek V4 Flash | Open-source | 47 | ~82 tok/s |
| Claude Haiku 4.5 | Premium | 37 | ~97 tok/s |
| Kimi K2.5 | Open-source | 37 | ~35 tok/s |
| Claude Sonnet 5 | Premium | Not yet scored | — |
| Claude Opus 4.8 | Premium | Not yet scored | — |
| Claude Opus 4.6 | Premium | Not yet scored | — |
| GPT-5.6 Sol | Premium | Not yet scored | — |
| GPT-5.6 Terra | Premium | Not yet scored | — |
| GPT-5.6 Luna | Premium | Not yet scored | — |
| Tencent Hy3 | Open-source | Not yet scored | — |
| MiniMax M2.5 | Open-source | Not yet scored | — |
Switching models with /model
In an interactive Command Code session, run /model to open the model selector. Pick the model you want and it applies to this session and to future sessions until you change it again. Premium models require Pro or higher; open-source models are available on every plan, including Go.
cmd # start an interactive session
/model # open the selector and pick a modelPlans and pricing
Command Code is a subscription with model usage at API rates. Each plan ships with monthly LLM credits. Credits roll over and never expire. Auto top-up keeps you running if you go over.
| Plan | Price/mo | LLM credits | Models |
|---|---|---|---|
| Go | $1 | $10 | Open-source only |
| Pro | $15 | $30 | Open-source + premium |
| Max 10× | $100 | $150 | Open-source + premium |
| Max 20× | $200 | $300 | Open-source + premium |
| Teams | $40 / seat | Pooled | Open-source + premium |
| Enterprise | Custom | Custom | Custom pool, SSO, audit logs |
Frequently asked questions
GPT-5.6 Sol or GPT-5.5?
Same pricing ($5/$30 per M). Sol is the newer OpenAI generation; switch with /model and compare results on your own workload until Sol has public benchmark scores.
Why is GPT-5.6 Sol not on the Intelligence Index?
Public aggregate benchmarks have not yet been run for the GPT-5.6 family. GPT-5.5 remains the current benchmarked OpenAI flagship.
Which Command Code model should I use?
For open models, Kimi, DeepSeek, Qwen, MiMo are all strong picks. For closed models, Claude Sonnet 5 is the recommended default — the best combination of speed and intelligence, and a drop-in upgrade from Sonnet 4.6. Switch to Claude Opus 4.8 (the newest Anthropic flagship) for the most capable long-horizon agentic coding, GPT-5.5 (Intelligence Index 60) for the absolute hardest reasoning, or Claude Opus 4.7 / GPT-5.4 (both 57) for top-tier work at lower cost. For fast lookups, Claude Haiku 4.5 or GPT-5.4 Mini. For open-source, Kimi K2.6 leads the open-weights tier (Intelligence Index 54).
Can I mix GPT-5.6 Sol with other models in a workflow?
Yes. Switch per session using /model. Common pattern: keep Sonnet 5 as the default and switch up to Opus 4.8 or down to Haiku 4.5 as the task calls for it.
Are open-source model prices fixed?
Open-source models are routed across multiple upstream providers for high availability. The price listed for each is the mean per-provider rate. Actual cost on a given request may vary slightly. The Usage page reflects the price charged.
Is Command Code free to try?
The Go plan starts at $1/mo with $10 in LLM credits. It covers open-source models only. Pro at $15/mo unlocks premium models with $30 in LLM credits.
Does Command Code train on my code?
No. Command Code does not train on your code or store your code snippets. taste-1 data is stored locally in your project directory.
Where can I track my usage?
The Usage page in Studio shows per-request cost, token counts, and which model ran. Settings > Billing lets you change plans, buy credits, or enable auto top-up.
Does Command Code replace my editor?
No. Command Code is editor-agnostic — it runs as a CLI and works alongside any editor (Cursor, VS Code, Zed, JetBrains, Neovim, etc.).
Ship code that matches your taste
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