OnePagent

OnePagent is a single page AI agent that runs entirely in the browser. It presents a workspace with a conversation list, system prompt editor, file upload area and tool panels, and it connects to a language model through the user's own provider profile and API key rather than a hosted backend. Provider profiles accept Anthropic compatible and OpenAI compatible endpoints, with model lists fetched from the API, per model context lengths, a default model and a reasoning effort selector. Separate settings cover image and video generation models and endpoints. Agent features include installable skills from a registry, a file, a GitHub repository or a form, swarms of agents, sub agents, todo tracking, hooks, context compaction and a plan mode and a looping mode. Tools can be extended with MCP servers over streamable HTTP or server sent events, with an optional CORS proxy since many MCP servers do not allow direct browser connections, and custom tools can run JavaScript in the browser. Web search is supported with basic and advanced modes. Conversations can be exported as Markdown or PDF, and a push and pull sync feature is available. It suits developers and power users who want a configurable agent they can use from any browser tab. The site publishes no pricing, and any model usage is billed by the provider whose key the user enters.