A Note on Phase-Structured Output Transitions under Strengthened Constraints

Description This record documents a short technical note intended to establish priority over the observation and phase-based classification of a non-continuous output transition under strengthened constraints. The note is deliberately restricted to a phenomenological description. Experimental configurations, procedural details, task-specific conditions, and potential mechanisms are intentionally omitted. No claims regarding optimization, performance, or applicability are made. This upload serves solely to fix the existence, naming, and high-level structure of the observed phenomenon while preserving full freedom for subsequent formal and explanatory reports. Abstract This note reports a phenomenological observation of a non-linear transition in output behavior under a progressively strengthened constraint. Across observations, output variability does not decrease continuously but instead undergoes a distinct transition at a critical regime. Beyond this transition, the observed behavior stabilizes into one of two qualitatively different fixed phases. These post-critical phases are distinguished as a Form-Fixed Phase, characterized by rigid adherence to output format, and a Structure-Fixed Phase, characterized by stabilization of internal relational structure. Prior to the transition, outputs remain in a pre-critical region where variability persists without convergence to either fixed phase. This note provides a conceptual definition and phase-based classification of the observed phenomenon, referred to here as the Critical Fixation Phenomenon. Experimental configurations, procedural details, task-specific conditions, and potential mechanisms are intentionally omitted to preserve the phenomenological scope of this report. A subsequent full report will address underlying explanations and formal analysis.