--- title: "Practitioner's Corner" canonical: "https://current.tinyfish.ai/issue/43/practitioners-corner" publication: "TinyFish" publisher: "TinyFish" language: "en-US" guide: "https://current.tinyfish.ai/llms.txt" permalink: "https://current.tinyfish.ai/issue/43/practitioners-corner" issue: 43 section: "practitioners-corner" description: "Lessons from the field—what we see building at scale" authors: ["Sevda Polat","Sable Whitford"] published: 2026-08-24 updated: 2026-08-21 articles: 14 --- # TinyFish > A journal for living in the agentic age [Read on the website]() ## Issue 43 — Practitioner's Corner Lessons from the field—what we see building at scale ### Builder Profile - [What Aman Gupta's Agents Don't Decide]() — By [Sevda Polat]() · Published 2026-08-20 · Format: Builder Profile Aman Gupta's team at Nubank built an agent architecture for over a hundred million customers largely by subtraction: deterministic sequences collapsed into single tools, toolsets held to five or fifteen options, routines translated from human procedure. The model decides only what couldn't be engineered away in advance. That's a precise account of where the model's authority ends. What the architecture doesn't yet specify is what a person receives when a live case comes back to them, because the scratchpad that keeps the agent moving isn't the artifact someone needs to pick up where it stopped. ### Lead Analysis - [The Intervention Horizon as a Design Parameter]() — By [Sable Whitford]() · Published 2026-08-20 · Format: Lead Analysis Agent architectures put a human approval step in the design and call it a safety measure. Approval only works if the person arrives before the outcome is locked in, with enough context to understand what they're approving and enough time to choose otherwise. Past that point, it records consent and offers no alternative. The last moment a human can still change what happens next deserves the same specification you'd write for latency, capacity, or failure behavior. Most systems never define it. ### Practitioner Interview - [The Queue Used to Be a Curriculum — A Compliance Analyst on What Agent Handoffs Actually Feel Like]() — Published 2026-08-20 Every workflow diagram has an arrow labeled "escalate to human." On one end of that arrow is an agent's confidence threshold. On the other end is a person with a queue, a regulatory clock, and a signature that converts whatever the agent assembled into an institutional record. Funke Adeyemi sits on the receiving end. ### Evidence Sidebar - [Competence Has a Carrying Cost]() — By [Sevda Polat]() · Published 2026-08-20 After working alongside AI polyp-detection tools, endoscopists at four Polish centers saw their unassisted adenoma detection rate [fall from 28.4% to 22.4%](https://pubmed.ncbi.nlm.nih.gov/40816301/). The retrospective design leaves room for confounders — workload shifts, temporal changes. But the direction is consistent with what a [2025 meta-analysis](https://pubmed.ncbi.nlm.nih.gov/40455501/) of procedural skills quantified more precisely: accuracy-based skills lose roughly half their acquisition gains within 6.5 months of nonuse. Intermittent practice was a significant moderator, which means the decay responds to countermeasures — if someone designs them in. ### Reading List - **Building Customer Support AI Agents at 100M-User Scale** — [Source]() — Published 2026-08-20 Nubank's KDD paper on bridging offline evaluation metrics and live customer satisfaction at production scale. - **Anatomy of a Frontier Lab Agent Intrusion** — [Source]() — Published 2026-08-20 Hugging Face traces 17,600 attacker actions after an evaluation agent broke out of its sandbox. - **Measuring Agents in Production** — [Source]() — Published 2026-08-20 Field study of deployed agents finds most teams deliberately cap autonomy at around ten steps. - **A Meta-Analysis of Automated Vehicle Takeover** — [Source]() — Published 2026-08-20 Establishes that how fast humans grab control and how well they use it are independent variables. - **Takeover Time, Time Budget, and Takeover Performance** — [Source]() — Published 2026-08-20 Formalizes the gap between when a human receives control and when they can actually exercise it. - **Procedural Skill Retention and Decay** — [Source]() — Published 2026-08-20 Meta-analysis across 1,344 effect sizes: half of accuracy-based procedural skills decay within 6.5 months of nonuse. ### Past Articles - [Who Pays for the Record]() — By [Sevda Polat]() · Published 2026-08-12 · Format: Evidence Economics When an AI agent canceled a gym booking in Australia earlier this year, the only record of what happened was screenshots taken by the person who deployed the agent. The person whose reservation vanished had nothing. Records cost money to produce — instrumentation, storage, retrieval, access controls — and in agent systems that cost lands by default on whoever eventually needs one, which is rarely the party equipped to pay it. Regulated industries settled this question decades ago. Agent systems haven't, and the economics of the gap are entirely predictable. - [Melissa Pan's Three Evidence Problems]() — By [Sevda Polat]() · Published 2026-08-12 · Format: Builder Profile A database recovery log carries its own interpretation. A multi-agent failure trace does not: in one recent study, six experts had to invent the failure categories before 150 traces could be classified at all. And production agent deployments generate evidence that researchers can reach only by interviewing the people who work inside. - [Melissa Pan Changed Instruments Twice, and What She Could See Changed With Them]() — By [Sable Whitford]() · Published 2026-08-05 · Format: Builder Profile I carried a pager for years attached to monitoring that rolled everything into averages at write time. Any question I hadn't thought to ask in advance wasn't hard to answer later. It was dead. The number was thrown out at ingest. - [Nobody Ever Blamed the Rate Limiter]() — By [Sable Whitford]() · Published 2026-08-05 · Format: Deliberate Constraint Most agents in production stop somewhere around ten steps and hand the work to a person. Easy to read that as the models running out of road. But we throttle a producer when the consumer downstream can't keep up — that's backpressure, and I have never once heard anyone look at a rate limiter and conclude the upstream service was incompetent. Ten steps starts to look like a measurement of the human: how much consequence one person can still hold in their head and refuse. Which puts the ceiling on agent deployment somewhere no model release measures. ## Other sections in Issue 43 - [Daily Brief]() - [Market Pulse]() - [Foundations]() - [Echoes]() - [Vision]() ## More - [Publication guide]() - [Issue archive]()