What problem does it solve? Building personas across a whole research population is slow and error-prone: transcripts are too large to read at once, quotes get paraphrased, and clusters get reverse-engineered to fit tidy archetypes. This Skill enforces a grounded, auditable pipeline that derives personas only from verified transcript citations. ## Core Features & Use Cases - Three-pass grounded synthesis: Extracts cited observations (Pass 0), clusters participants by behavior (Pass 1), then synthesizes personas with per-attribute evidence, support levels, and gaps (Pass 2). - Versioned persona records: Writes each run as a new draft version via write_persona_set, automatically superseding prior versions and refusing no-change re-runs. - Dual artifact delivery: Produces both a structured BigQuery record and a rendered Google Doc in a Drive Personas/ folder, with emergent-mode labeling when no study goals exist. - Use Case: After Analyst has tagged interviews for a population, run @Percy build personas for population_id=<id> to get clustered behavioral archetypes with verbatim quote evidence and a cohort-alignment report. ## Quick Start Ask the agent to build personas for a specific population by saying: build personas for population_id=<your_population_id> using the tagged transcript data.