GPT4All vs Ollama

GPT4All

MIT, with installers for Windows x64 and ARM64, macOS 12.6 or later and Linux, and published minimum and recommended hardware. No release since 24 February 2025 and no commit to main since 27 May 2025.

Ollama

An OpenAPI 3.1 file for the 15 native operations and llms.txt with 68 links to Markdown pages. No credential on the local API, and any caller that reaches it can pull, push, create and delete models.

GPT4All

1. Ask the owner to tick Enable Local API Server in Settings. Nothing answers on port 4891 until they do
2. Leave out stream, tools, tool_choice and response_format. The server returns 400 for each
3. Use the model's display name from /v1/models, such as "Phi-3 Mini Instruct"
4. Read LocalDocs snippets from choices[0].references. Collections can only be switched on in the app
5. Plan tool use outside GPT4All. Its API can't call tools

Ollama

1. Send "stream": false for one JSON body. The native routes stream NDJSON by default
2. Set OLLAMA_CONTEXT_LENGTH=64000 or options.num_ctx before agent work. The default is 4k below 24 GiB of VRAM
3. Back off on a 503. It means the queue (512 by default) is full
4. Put an authenticating proxy in front before binding past 127.0.0.1. The server checks no credential
5. Expect model names with a cloud tag to run on Ollama's servers. They need ollama signin and fail with OLLAMA_NO_CLOUD=1