When responseSchema Can't Do $ref: Handling Recursive Schemas in Production with responseJsonSchema
Gemini's responseSchema is an OpenAPI subset with no $ref or $defs, so it can't express shared definitions or recursion. Here's how I moved to responseJsonSchema to reuse localized fields and handle a recursive category tree in production.
When a Whole Chapter Vanished From My Long-PDF Summary — Field Notes on Auditing Coverage
Chapter-wise summarize-then-merge works well on long PDFs, but a lost extraction or a merge step can drop an entire chapter while the pipeline finishes without a single error. This walks through catching those silent drops with one number—coverage—and re-running only the chapters that fell out.
Never Generate the Same Narration Twice: Cache-Key Design and Invalidation for Gemini TTS Output
For apps that replay the same audio over and over—meditation, language learning, storytelling—caching the Gemini TTS output itself drives the variable cost to near zero. This is a working design: how to build a cache key that text alone can't cover, a two-tier server-plus-device cache, and an invalidation policy that survives model shutdowns like the August 17 image-model deprecation.
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.
Gemini API System Instructions and Prompt Design — Practical Techniques to Dramatically Improve Output Quality
Practical techniques for designing system instructions and prompts that produce stable, high-quality output from the Gemini API. Includes working code examples for format control, few-shot learning, temperature tuning, and error handling.
When gemini-embedding-2 Retrieval Feels 'Almost Right,' Check task_type First
When gemini-embedding-2 search misses in a frustrating near-hit way, the cause is often a missing or mismatched task_type. Here is how to align document and query intent, plus the code and a tiny harness to prove the difference on your own data.
Render Structured Output Field by Field as It Streams: Safe Partial JSON Parsing
With responseSchema streaming, the screen stays blank until the JSON closes. This walks through a partial parser that safely completes unclosed JSON, plus anti-flicker fencing that never lets a field move backward, and shows how time-to-first-field dropped from about 2.4s to 0.4s in practice.
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.
Measure a Managed Agent's Behavior Against Fixed Scenarios Before It Reaches Production
The public-preview Managed Agents run autonomously inside an isolated sandbox, so a small prompt or config change can quietly shift their behavior. Diffing the output once, the way you would for a single prompt, is not enough. Here is how to build a regression harness that runs fixed scenarios repeatedly and judges on pass rate, plus a shadow to canary to full promotion with automatic rollback, all with runnable Python.
Catching only the deprecations that touch you — feeding the official changelog to url-context
I found out an image model was being shut down three days before the deadline. Here is a deprecation radar that reads the official changelog through url-context and surfaces only the models I actually use, with working Python and the over-alerting tuning I had to do in production.
Catch Near-Duplicate Posts Before You Publish — a Topic-Cannibalization Gate with Gemini Embeddings
Once a blog passes a few hundred posts, new articles start cannibalizing old ones in search. This walks through a pre-publish gate that embeds each post's meaning with gemini-embedding-2 and blocks drafts that sit too close to something you already wrote — with runnable code and how to pick the thresholds.
Catching the Rows That Quietly Failed Overnight: A Per-Row Retry Ledger for the Gemini Batch API
A SUCCEEDED batch job is not the same as all-rows-succeeded. From running nightly batches as a solo developer, here is a per-row result ledger, a transient-vs-permanent failure classifier, selective retries, and a guard against retrying permanent failures forever, with a working SQLite state machine.