Ephemeris · Issue 046 Wednesday · 03 Jun 2026 · Zürich

Today's issue

The agents went to work — shipping pull requests from a chat box, reading a thousand codebases for flaws, auditing the spreadsheet you forgot to check. Every one of them is a new thing to defend.

Ephemeris.

Ephemeris · Issue 046 01 / 6 · Vercel
Security · LLM Ops

Someone is reselling your model calls.

Inference theft is the quiet line item nobody budgets for: an attacker funnels your paid API quota into a product they sell as their own, and you find out from the invoice. Vercel's piece explains why rate limits and API keys miss it — the abuse looks like ordinary traffic — and makes the case for catching it at the request layer with BotID instead of after the bill lands.

incident ······ inference theft
calls billed ··· 4,812,000
authorised by ·· your API key
resold as ····· "free AI chat"
caught by ····· rate limit  →  no
UNBUDGETED
Ephemeris · Issue 046 02 / 6 · PostHog
Agents · Dev Tools

Ship code straight from Slack.

PostHog wired an agent into Slack: mention it with a feature request and it spins up a sandbox, writes the code, runs the tests, and opens a pull request a human still reviews. A two-stage classifier routes each ask. Over two weeks it merged 116 contributions — a concrete look at what happens when the people closest to the problem can file a fix, not just a ticket.

1 · ask@PostHog add a dark-mode toggle
2 · agentsandbox · writes code · runs tests
3 · reviewopens a PR, a human merges
116contributions merged in two weeks
Ephemeris · Issue 046 03 / 6 · Anthropic
Security · AI

An AI read the code and found ten thousand ways in.

Project Glasswing hands select organisations a security-tuned model, Claude Mythos, that scans their codebases for vulnerabilities. Early partners surfaced more than 10,000 high- and critical-severity flaws. This expansion widens access from roughly 50 to about 150 organisations across 15-plus countries, weighted toward critical infrastructure — power, water, healthcare, communications — where an unpatched flaw is more than a bug.

10,000+
high- and critical-severity flaws found by the first cohort of partners.
PowerWaterHealthcareCommunications
Ephemeris · Issue 046 04 / 6 · OpenAI
Dev Tools · Agents

Codex opens up beyond engineers.

OpenAI gave Codex three extensibility hooks — plugins, sites, and annotations — pitched not only at developers but at analysts, marketers, designers, and investors. The bet is that the agent is more useful when it plugs into the tools a team already runs and can publish or annotate what it builds, rather than living behind a terminal.

01

Plugins

Connect Codex to the tools and data a team already uses.

02

Sites

Publish what the agent builds as a shareable page.

03

Annotations

Leave inline notes the agent reads and acts on.

for analysts · marketers · designers · investors · engineers
Ephemeris · Issue 046 05 / 6 · PostHog
Product · Analytics

Put the numbers where the decision happens.

Analytics users never see still drive the product they pay for. PostHog catalogues five ways teams expose data to customers and argues the craft is placement and trust, not dashboards.

The pattern that fails is the one buried in a separate reports tab. The ones that work sit inline, at the moment a customer is deciding something — and they hold to sub-minute latency, because numbers people don't trust they stop reading.

Treat customer-facing analytics as a core feature with an owner, the piece argues, not a side project the data team squeezes in. Scope every figure to the viewer who's allowed to see it.

Five patterns in the wild

Embedded dashboard
Vercel
Inline metric at the decision
Booking.com
Public leaderboard
Product Hunt
Gamified contribution graph
GitHub
Augmented internal data
in-product
→ Endpoints turns a saved insight into a fast, versioned, authenticated API — no custom backend to ship.
Ephemeris · Issue 046 06 / 6 · via @ProductsAndStartups
Tools · Agents

A second reader for the spreadsheet you trust.

excel-hygiene is a small Claude skill that audits an .xlsx file two ways: a Python pass catches the mechanical errors — numbers stored as text, formulas overwritten with static values, truncated sums, percentages off by 100× — while the agent reasons over the Panko–Halverson error taxonomy for the logic mistakes a machine check misses. Clone it into your skills folder and ask it to look.

ABC
1Revenue=SUM(B2:B9)✓
2Q1"12000" ⚑ text
3Q213400
4Margin0.62 ⚑ formula → static
5Growth8 ⚑ pct as whole

check_excel.py flags the mechanical errors · the agent reasons about the rest

End of Issue 046 Back to top ↑

That's today.

Six picks on a thin day — the thread running through them is agents doing real work, and the new surfaces that work leaves exposed.

Sources today

Vercel
PostHog
Anthropic
OpenAI
Telegram · @ProductsAndStartups

Rubric

Tools you could adopt this week. Dev tools & agentic coding. Privacy & security when the signal is high. Skip the marketing.

Issue

No. 046
2026-06-03
Zürich · 08:00