This post goes over how to set up OpenCode with Ollama.

Prerequisites

OpenCode:

brew install opencode

Ollama:

brew install ollama

Ollama

Start Ollama:

ollama serve

Ollama by default uses a context window size of 4096 tokens. For tasks that require large context like web search, agents, and coding tools, set the context window to at least 64000 tokens:

OLLAMA_CONTEXT_LENGTH=64000 ollama serve

Install qwen2.5-coder:

ollama pull qwen2.5-coder:latest

OpenCode

Open OpenCode > ⌘P > Settings (⌘,) > Providers > Custom provider > + Connect.

Fill out the custom provider fields:

• Provider ID:

  ollama
  

• Display name:

  Ollama
  

• Base URL:

  http://localhost:11434/v1
  

• Model ID:

  qwen2.5-coder:latest
  

• Model Display Name:

  Qwen2.5 Coder
  

Click Submit.

To delete a manually configured model, edit the global config ~/.config/opencode/opencode.jsonc.

Ollama is connected and the model is ready for use!