You'll notice
The '[1m]' long-context model label can now trigger from a remembered model id, not just the current request
What
Claude Code adds a [1m] tag to a model's name when that model supports a 1 million token context window (the amount of text it can consider at once). Previously this check only looked at the model named in the current request or the active agent. Now it also checks a model id stored from earlier in the session, so the tag can be applied based on a model chosen in a prior turn, not just the current one.
Why
This widens the situations where the [1m] label correctly appears, so it is less likely to be missing when a long-context model is actually in use.
One source agreesOne thing we can check says the same as this entry.
Anthropic's release notes agree
Fixed --resume dropping the 1M context window ([1m]) when the resumed session's model family differs from the configured default model