Start with a provider and a model
A short first-connection guide helps users choose an official provider, find its key-management page and check the connection without generating content. Settings can stay collapsed, model choices are remembered, and the interface defaults to English with a Chinese switch.
Make the API call inspectable
The Java service adapts seven manufacturers' official protocols. The current catalogue has 60 integration entries, including four batch entries. A fixed destination allowlist rejects third-party gateways and custom URLs. Users can inspect 24 actual Java and JavaScript source files and their SHA-256 fingerprints inside the site.
Keep the interaction manageable
Streaming chat reveals responses progressively. Controls reflect each model's supported settings and are validated again by the server. Local chat-text saving is optional and off by default; keys and attachments are excluded, and turning saving off removes the browser's saved history copy.
Deployment and evidence
The application runs as another WAR in one existing Tomcat 9 JVM. The latest release passed 39 Java and six JavaScript tests, alongside browser checks for onboarding, language switching, remembered models, local history and source viewing. Protocol tests use simulated upstream services; they do not establish access to every model for every provider account.