The Day We Went From 30 Categories to 34 — Reclassifying 1,180 Assets Instead of 8,142
Adding categories to a taxonomy does not require reclassifying everything. Here is how embeddings and confidence margins narrowed a backfill from 8,142 assets to 1,180, with the numbers.
Images Made With a Retiring Model Can Never Be Made Again — Tracking Regenerability in a Ledger
When Gemini's image generation models shut down on August 17, the assets you made with them can no longer be reproduced the same way. Here is the ledger design and code I use to decide, before the deadline, which assets are regenerable and which must be frozen.
Closing the Failures That Never Throw: Normalizing Gemini API Responses into a Discriminated Union
An HTTP 200 with an empty body will never reach your catch block. Here is how I normalize finishReason and blockReason into a discriminated union, and let a never check turn missed cases into compile errors.
Google Sheets API × Gemini API: A Python Data Pipeline — No Apps Script Required
Learn how to build a fully Python-based pipeline that reads data from Google Sheets, processes it with Gemini API, and writes results back — without touching Apps Script. Covers service account auth, structured output, and rate limit handling.
Your Apps Script Gemini Automation Fails Every Month-End — Budgeting Against the UrlFetch Daily Quota
Apps Script automations that call Gemini stall on the UrlFetch daily call quota — a separate ceiling from the 6-minute limit and trigger counts. Here is a daily budget governor with backlog carry-over that keeps the job running on busy days, with working code and a verified simulation.
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.
When My Paid Gemini Chat Bill Came in at Double the Estimate — Field Notes on Per-Request Token Accounting to Plug the Cost Leaks
From a real overrun where my paid Gemini chat SaaS bill nearly doubled the estimate, here is how I logged token usage per request, traced where cost was leaking, and plugged three specific gaps. Recording usage_metadata and reconciling it against the invoice is the starting point.
One File Search Store for Many Apps: Splitting Retrieval With customMetadata and Chunk Config
Put several apps' FAQs in a single Gemini File Search store and metadataFilter can silently return empty grounding, or answers get split across chunk boundaries. Here is the customMetadata design, the AIP-160 filter-syntax trap, and measured chunkingConfig tuning.
When Context Caching Didn't Lower My Gemini Bill — Field Notes on Measuring the Real Hit Rate
When Context Caching is enabled but the Gemini API bill barely drops, this field note measures the real hit rate from usage_metadata, separates TTL churn from fragmentation, and walks through a staged recovery.
Designing Batch Image Costs with Nano Banana 2 Lite: Decide by Measuring
How to fold the fastest, cheapest image model, Nano Banana 2 Lite, into high-volume generation: measuring per-image cost, a two-tier setup with a quality model, and retry handling grounded in real numbers.
Gemini 3 Multi-Tool Agents: Function Calling + Built-in Tools + Context Circulation in Production
A hands-on look at Gemini 3 multi-tool agents: combining Built-in Tools with Function Calling, Context Circulation, and parallel tool IDs, with measured latency numbers and the pitfalls I hit in production.
When Two Managed Agents Fight Over the Same Repo: External Leases and Fencing for Isolated Sandboxes
Every Managed Agents run gets its own isolated sandbox, so a local lock cannot stop two runs from touching the same repo or record. Here is how I serialize them safely with an external lease and a fencing token.