Retiring Prompt Assets That Refuse to Die — A Ledger for Paths Static Analysis Cannot See
A prompt I had supposedly consolidated away was still running daily. Here is the retirement ledger I built to cross-check static references, flag defaults, observation windows, model end-of-life dates, and cache effectiveness.
When to Hand Conversation State to the Server: previous_interaction_id vs. Pruning History Yourself
With the Interactions API, passing previous_interaction_id lets the server hold conversation state so you stop resending history. But a large tool output that lands mid-conversation can't be pruned afterward, and every later turn drags its weight. Here is a branching design that mixes server-side state with client-side pruning, plus a thin, working Python wrapper.
Architecting a Multi-Tenant SaaS on Gemini API — Tenant Isolation, Usage Metering, and Runaway Cost Defense in Production
A field-tested blueprint for serving Gemini API to multiple tenants on a single backend — covering tenant isolation choices, per-tenant rate limiting in Redis, request-level usage metering for billing, and runaway-cost defenses.
Gemini API Semantic Router: Implementation Notes for Splitting Flash and Pro Smartly
Implementation notes for building a production-grade semantic router that automatically dispatches Gemini queries between Flash and Pro. Includes Python and TypeScript working code, a two-stage design pattern, and seven implementation insights from running it inside an indie wallpaper app.
Keeping a Long-Running Managed Agent Alive Across Sandbox Recycling — Durable Checkpoints and Idempotent Resume
A Managed Agents sandbox can be recycled out from under you. Before 40 minutes of work resets to zero, we design a durable checkpoint that pushes progress outside the sandbox and an idempotent resume that never runs a side effect twice. With working SQLite code.
Setting a Token Budget Per Free User: Balancing AdMob Revenue Against AI Feature Cost
Rate limits protect requests per minute. They do nothing for the invoice that arrives at the end of the month. Here is how I derive a per-user token budget from ad revenue, keep the ledger inside a single call wrapper, degrade gracefully at a soft cap, and detect abuse with one concentration ratio.
When Your Knowledge Base Shifts Mid-Run: Pinning File Search to an Execution Epoch for Consistent Agent Grounding
When a File Search store is updated while a Managed Agent is running, a single execution can mix old and new grounding. Borrowing MVCC ideas, pinning an execution epoch keeps one agent run's evidence consistent. Here is the design and implementation.
Designing So the Next Shutdown Notice Doesn't Cost You an Afternoon: Isolating Gemini Behind a Single Port
The morning an image model shutdown notice landed, I couldn't say where my app touched that model. This is the design I use now: collapse Gemini dependencies into one port, with fallback and a CI deadline guard, shown as working code.
Building Conversational Translation Into an App: Speech-to-Speech With the Live API
A design walkthrough for adding speech-to-speech conversational translation to an app with Gemini 3.5 Live Translate and the Live API, covering session lifetime, automatic language switching, latency budgets, and streaming cost, with working code.
Your Night Batch Is Causing the Morning 429s — Priority Admission Control for a Shared Gemini Quota
When bulk jobs and interactive features share one project's RPM/TPM, the bulk lane wins by default. A priority token bucket design with measurements: 429 rate 3.2% down to 0.03%.
Routing Between Local Gemma 4 and the Gemini API Cut My Bill from ¥32,000 to ¥9,000 — A Production Hybrid Router Design
How I cut a ¥32,000/month Gemini API bill to the ¥9,000 range with hybrid inference: routing design, a full Python router, production pitfalls, and how Gemma 4 arriving on the Gemini API in July 2026 changes the decision.
Folding Scattered Call Sites Into One Front Door: Migrating to the Interactions API for Automation
With the Interactions API now generally available, Gemini's calls can settle behind a single entry point. Here is a migration design for folding scattered call sites — generateContent, Batch, and homegrown agent loops — into one front door without breaking anything, complete with a working adapter layer.