--- url: https://pencel.ai/docs/reference/supported-models.md description: >- The AI models Pencel supports (Pencel Auto, Pencel Private, Claude Opus 5.5, Claude Sonnet 5, GPT-6 Sol, Gemini 3.8 Flash and Gemini 3.1 Pro) and how to choose one. --- # Supported models Pencel works with leading AI models from Anthropic, OpenAI and Google. Most people never need to pick one: Pencel chooses a sensible model for you. This page explains your options if you want more control. ## Pencel Auto and Pencel Private These two options run on Pencel credits, so there are no API keys to manage. * **Pencel Auto** lets Pencel choose the model for you. Today it runs on GLM-5.3, an open model hosted by Fireworks AI, picked for good results at a low cost. Each reply shows which model actually ran. * **Pencel Private** uses the same model, but your requests go only to a model provider that doesn't keep them, and Pencel never logs their content. Your own history and memory on your computer are unaffected. It's marked **Zero data retention** in the model picker. Both need Pencel credits: a paid plan, or your free starter credits while they last. With only your own API key, they appear locked. See [Accounts, plans and credits](https://pencel.ai/docs/getting-started/accounts.html). ## Individual models | Model | Made by | ID | Good for | Relative cost | |---|---|---|---|---| | **Claude Opus 5.5** | Anthropic | `claude-opus-5-5` | The hardest reasoning, careful writing, complex instructions | Higher | | **Claude Sonnet 5** | Anthropic | `claude-sonnet-5` | A strong everyday default: good quality at a moderate cost | Medium | | **GPT-6 Sol** | OpenAI | `gpt-6-sol` | Strong general-purpose reasoning and broad knowledge | Medium | | **Gemini 3.1 Pro (preview)** | Google | `gemini-3.1-pro-preview` | Long documents and detailed analysis | Medium | | **Gemini 3.8 Flash** | Google | `gemini-3.8-flash` | Fast, simple, high-volume work at the lowest cost | Lower | Gemini 3.1 Pro is a preview model, so Google may change or replace it at short notice. ## Managed or your own key Every model above works either way: * **On Pencel credits** (a paid plan or starter credits), every model is available with no keys to set up. Usage comes out of your credits. * **With your own API key**, add a key for a provider in **Settings ▸ Credentials** and you can use that provider's models. Requests go straight from your computer to the provider, and you pay the provider directly. No credits are used. If you have both, your own key wins for that provider's models. | Provider | Where to get a key | Models it covers | |---|---|---| | Anthropic | [console.anthropic.com](https://console.anthropic.com) | Claude Opus 5.5, Claude Sonnet 5 | | OpenAI | [platform.openai.com](https://platform.openai.com) | GPT-6 Sol | | Google | [aistudio.google.com](https://aistudio.google.com) | Gemini 3.8 Flash, Gemini 3.1 Pro | A model you can't use yet shows **Add a … key to use** in the picker, or **No API key** in Settings. ## Choose a model You can set a model in three places. Pencel uses the first one that applies: 1. **In the message box.** On Home and in every room, the message box has a model picker showing the current model's name. What you pick there applies to that conversation. 2. **On an agent.** In **Studio ▸ Agents**, open an agent and set **Preferred Model** on the **Profile** tab. Choose **Use workspace default** to clear it. See [Create a custom agent](https://pencel.ai/docs/guides/creating-your-first-agent.html). 3. **For everything else.** **Settings ▸ General ▸ Default Model** sets the model used when nothing more specific is chosen. Leave it on **System default** and Pencel picks for you. The label shows which model that is right now: a balanced model from a provider you have a key for (such as Claude Sonnet 5), or Pencel Auto if you have no keys and are on Pencel credits. ### Which one should I pick? * **Not sure?** Use **Pencel Auto**, or **Claude Sonnet 5** with your own key. * **Customer-facing writing, proposals, tricky judgment calls:** Claude Opus 5.5. * **Very long documents:** Gemini 3.1 Pro or Claude Sonnet 5. * **Lots of simple, repetitive work where cost matters most:** Gemini 3.8 Flash. * **Sensitive material:** Pencel Private. ::: tip Keep costs down Use a cheaper model for routine agents and save Claude Opus 5.5 for the work that needs it. **Settings ▸ Cost & Usage** shows where your credits go. See [Control what you spend](https://pencel.ai/docs/guides/managing-costs.html). ::: ## Older models If you picked a model Pencel no longer offers, it stays selected and shows as "no longer offered" in the picker. Switch to one of the models above when you're ready. ## Related * [Accounts, plans and credits](https://pencel.ai/docs/getting-started/accounts.html) * [Settings](https://pencel.ai/docs/reference/settings.html) * [Data handling](https://pencel.ai/docs/privacy-and-security/data-handling.html)