The Complete LLM Parameters Cheatsheet (2026)

Every parameter, every provider, every use case - one place, so you never have to Google “top_p vs top_k” again. I spend most of my days at shipping multi-agent systems. And for the first few months, I had a confession: every time I opened a new API doc, I’d squint at temperature, top_p, presence_penalty, frequency_penalty, stop, response_format, reasoning_effort… and quietly tune by vibes. Every blog post explains temperature. A few cover top-p. Almost none explain all the parameters, across all providers, with actual settings you can copy into production.