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+---
+name: "Constrain thinking traces in chat panel"
+---
+
+# Story 174: Constrain thinking traces in chat panel
+
+## User Story
+
+As a user chatting with Claude in the web UI, I want thinking traces to be height-constrained and visually distinct, so that extended thinking doesn't flood the conversation and push real content out of view.
+
+## Acceptance Criteria
+
+- [ ] Chat WebSocket protocol delivers thinking tokens separately from regular text tokens (not as a string prefix)
+- [ ] Thinking tokens render in a fixed max-height (96px) scrolling container in the chat panel, matching the existing ThinkingBlock style
+- [ ] ThinkingBlock auto-scrolls to bottom as new thinking tokens stream in
+- [ ] When thinking ends and regular text starts, the thinking block stops growing and regular output renders normally below it
+- [ ] The literal [thinking] prefix no longer appears in rendered chat output
+
+## Out of Scope
+
+- TBD