Claude Opus 4.8 vs GPT 4o Search Preview

Claude Opus 4.8

Anthropic · text, image, pdf → text

Claude Opus 4.5 is Anthropic’s latest frontier reasoning model, optimized for complex engineering, agentic workflows, and long-horizon computer use. It features strong multimodal capabilities, improved resistance to prompt injection, and a new Verbosity parameter to control token efficiency. With advanced tool use, extended context, and multi-agent support, Opus 4.5 excels in autonomous research, debugging, planning, and spreadsheet/browser operations.

GPT 4o Search Preview

OpenAI · text, image → text

Using the Chat Completions API, you can directly access the fine-tuned models and tool used by Search in ChatGPT. When using Chat Completions, the model always retrieves information from the web before responding to your query. To use web_search_preview as a tool that models like gpt-4o and gpt-4o-mini invoke only when necessary, switch to using the Responses API. Currently, you need to use one of these models to use web search in Chat Completions: gpt-4o-search-preview gpt-4o-mini-search-preview Web search parameter example import OpenAI from "openai"; const client = new OpenAI(); const completion = await client.chat.completions.create({ model: "gpt-4o-search-preview", web_search_options: {}, messages: [{ "role": "user", "content": "What was a positive news story from today?" }], }); console.log(completion.choices[0].message.content); Output and citations The API response item in the choices array will include: message.content with the text result from the model, inclusive of any inline citations annotations with a list of cited URLs By default, the model's response will include inline citations for URLs found in the web search results. In addition to this, the url_citation annotation object will contain the URL and title of the cited source, as well as the start and end index characters in the model's response where those sources were used.