OpenRouter is useful for OpenAI-compatible applications because it preserves a familiar development pattern while changing what happens behind the request. Many applications are already built around OpenAI-style chat completions, message arrays, streaming responses, tool calls, JSON outputs, and SDK configuration. OpenRouter allows those applications to keep much of the same structure while routing requests through a broader model and provider layer. The first migration step

Claude Opus 4.8 expands what can fit inside a single AI working session. Long files, dense PDFs, large repositories, research folders, legal bundles, policy archives, technical documentation, and multi-document projects all become easier to work with when the model can reason across a larger amount of material. The context window is the space where instructions, files, messages, code excerpts, tool results, images, PDF pages, and conversation history are held while the model

ChatGPT 5.5 is most useful for research when the task requires more than a direct answer. Research work usually involves current information, competing sources, uploaded files, internal documents, data tables, and claims that need to be checked before they are used. A strong research workflow does not only collect information. It verifies sources, separates evidence from interpretation, identifies uncertainty, and turns scattered material into a structured conclusion. This is