ProjectBuild an Agentic Content Studio: the explanation · Module 5: Low-level design: data, deck spec, API and events · part 7 of 22
Part 7 · Module 5: Low-level design: data, deck spec, API and events

Module 5: Low-level design: data, deck spec, API and events

24 min read·
About 45 minutes · Needs: Module 4 (high-level design) · Code: backend/app/models/__init__.py, backend/alembic/versions/, backend/app/schemas/deck.py, frontend/src/render/types.ts, backend/app/api/routes/

Where this fits

WHERE THIS FITS Slidesmith Studio this module BROWSER React FRONT DOOR AND API nginx, FastAPI BACKGROUND AGENTS LangGraph MODELS Ollama RENDERING Playwright DATA Postgres 17 OPERATIONS evals, Docker, Cloud Run Studio app React pages /render page same renderer nginx proxy, headers Auth sessions, CSRF Brand kit onboarding, uploads Projects deck spec, edits Job runner progress over SSE Research search, facts Strategist outline Designer slide JSON Check fit, else repair LangGraph pipeline state graph, JSON repair Ideas post ideas from pillars qwen3.8:27b Ollama, local GPU Web search Ollama API Chromium render, measure Exports PDF, PNG, ZIP, HTML PostgreSQL users, decks, jobs Uploads disk or GCS Evaluation suites, gate Insights usage, timings Containers Docker Compose Deploy Cloud Run, CI/CD
This module (blue) describes what the API stores in Postgres, what it accepts and returns, and the events a job sends while it runs.

Module 4, the high-level design, drew the boxes: a browser, nginx, one FastAPI process, the agents, Chromium and Postgres. This module opens the lines between them. It answers four questions a builder asks before writing a feature: what is stored, what shape is the deck, which calls exist, and what does a running job tell the browser.

The rest of this project is yours to keep

This project is bought on its own, once, and stays readable afterwards, including the parts added to it later.

Or open everything with a plan