Jan vs TextGen

Jan

Apache-2.0, with installers for macOS, Windows and Linux plus Flathub and the Microsoft Store. No release since 0.8.4 on 23 July 2026, while a security fix waits on main.

TextGen

AGPL-3.0 with no telemetry, and a local API on 127.0.0.1:5000 that checks the Host header, limits CORS to localhost and separates an admin key from the caller's key. No release since v4.9 on 20 May 2026, no code commits since 31 May, no test suite, and ten security advisories in the year, all fixed.

Jan

1. Ask the owner to start the server (Settings, Local API Server) or run jan serve. Nothing listens until then
2. Call http://127.0.0.1:1337/v1 for the app and localhost:6767/v1 for jan serve. The ports differ
3. Read /openapi.json from the running server, not the spec on the docs site, which describes the retired Cortex API
4. Branch on the status code. Error bodies are plain text
5. Keep the bind at 127.0.0.1 on 0.8.4. Trusted Hosts is ignored on 0.0.0.0 until the next release

TextGen

1. Ask the owner to launch with --api. Nothing listens on port 5000 without it, and a model must be loaded first
2. Call http://127.0.0.1:5000/v1. Any Host header other than localhost or 127.0.0.1 gets 400 Invalid host header unless --listen is set
3. Send the key as Authorization: Bearer on OpenAI routes and as x-api-key on /v1/messages. Model loading needs the admin key
4. Read http://127.0.0.1:5000/docs or modules/api/typing.py for parameters. max_tokens defaults to 512 on chat completions
5. Run tool calls yourself. The API returns finish_reason: "tool_calls" and executes nothing on the server
6. Use the repository name oobabooga/textgen. The old text-generation-webui URL redirects