Keeping Tools Visible While Blocking a Tool Call

An agent framework exposes three tool-choice settings: auto, forced/required, and none. For one specific turn — a final "summarize what happened this session" step — you want the model to still see the full list of available tools, so its summary can reference what capabilities exist, but it must respond in plain text only, with zero chance of emitting a tool call on this turn.

Which tool-choice setting fits this turn?