Cumbersome: AI LLM API Client

IMPORTANT: Requires your own API keys from OpenAI, Anthropic, OpenRouter, Google AI Studio, Z.ai, or Vercel AI Gateway, or your own OpenAI-compatible endpoint.

I built Cumbersome because consumer AI apps kept dumbing things down. Cumbersome is the manual transmission of AI apps: more complex, but with far greater control.

WHY I BUILT THIS

Consumer AI providers like ChatGPT and Claude route requests to cheaper models to keep their costs down. They charge monthly subscriptions whether you use them once or a thousand times. They hide the technical controls that let you tune how models respond. And they lock you into one provider.

I wanted an AI client that connects directly to AI provider APIs. I wanted to pick exactly which model I use and know I'm getting it. I wanted to compare different models on the same prompt. I wanted to pay per use instead of subscriptions. So I built it.

SUPPORTED PROVIDERS

Bring your API keys, or add your own OpenAI-compatible endpoint, for any of the following:

— ChatGPT / OpenAI
— Claude / Anthropic
— Gemini / Google AI Studio
— OpenRouter multi-provider
— Vercel AI Gateway multi-provider
— Z.ai
— OpenAI-compatible custom endpoints (beta), including Ollama, Azure, LM Studio, Groq, Together, and self-hosted backends

WHAT YOU GET

— A simple API client.
— Switch providers or AI models mid-conversation.
— NEW! Local browser tool use. AI can use your local browser to search and browse pages.
— iCloud sync across devices. (Nothing saved to our servers.)
— Face/Off Mode. Three responses generated at once. An AI judge picks the best.
— Extended thinking. Turn on model reasoning for OpenAI and OpenRouter.
— Full parameter control. Temperature, tokens, system prompts. API playground controls on your phone.
— Concurrent chats. Multiple conversations streaming in parallel.
— Edit any message. Remove tangents, fix mistakes, reshape your conversation history.
— Rich content. Markdown, LaTeX math, code blocks with copy, attachments.
— Export everything. Copy conversations, export JSON, or share deep links to specific chats.
— Collapse long messages. Fold them to keep your place in deep conversations.
— Siri and Shortcuts. Ask questions hands-free or build automations in the Shortcuts app.
— Accessible. VoiceOver, Dynamic Type, Voice Control, full keyboard navigation, reduced motion.
— Native on iPhone, iPad, and Mac.

THE DEAL

The app is free. You pay providers directly for API access.

I'm Peter, an indie developer in Portland, Oregon. No VC money. No growth hacking. Just a tool I wanted to exist.