The Nest

HarpyWatch's writing on monitoring, uptime, and the things that break quietly.

The vulnerabilities agents write fresh

Ask an agent for a login flow and you tend to get a ?next= parameter redirected to whatever it contains. It is the obvious implementation, it is an open redirect, and the remedy was documented years before the model was trained.

article 6 min read

What thirty seconds of checking would have caught

A catalogue of small, boring, real failures — a www that resolves nowhere, a redirect that drops to http, a response that is not actually compressed — each one cheap to see from outside.

article 6 min read

The debt you take on when a customer tells you first

An outage costs what it costs. Being informed of it by the person it happened to costs something separate, it accrues, and it is charged against the next incident rather than this one.

article 5 min read

Verify the artefact, not the diff

Four agents changing one codebase means four diffs nobody has time to read end to end. The answer is not fewer agents: it is checking the deployed site, which costs the same however many changes arrived.

article 6 min read

Nothing fails when a page gets heavier

Generated markup is verbose, imports whole libraries for one function, and inlines assets because that works. Every test still passes. The cost lands on a phone on a slow connection, months later, as a number with no cause attached.

article 6 min read

The security header an agent widened to make the feature work

A strict Content-Security-Policy is usually the thing standing between an agent and the feature it was asked to add. Widening it is the path of least resistance, it is never mentioned in the summary, and nothing about the site looks different afterwards.

article 6 min read

Set it up in an afternoon and then stop

Adopting monitoring for a small site is five decisions, not a project. Here is what each one actually involves, and why finishing a rough version beats designing a perfect one.

article 6 min read

Staging configuration travels, and agents help it

A canonical tag pointing at staging, a noindex that shipped, a test API key in production. Each is invisible on a developer's machine and expensive live, and copying config between environments is the fastest way to make something work.

article 6 min read

Monitor the site nobody is looking at yet

The instinct is to add monitoring once a site has traffic worth protecting. That gets it backwards: an empty site is the one failure mode nobody reports, because your first hundred visitors leave instead.

article 6 min read

The API contract changed underneath the frontend and nothing failed

One agent edits the backend, another edits the frontend, a field quietly changes type, and every build stays green. The screen renders blank where a number belongs, and only something watching the deployed endpoint will tell you.

article 6 min read

Four hops to nowhere: what refactors do to your redirects

Every restructure moves URLs, and every move adds a redirect. Nobody ever removes one. The result is a chain a crawler stops following and a browser spends a second on before it sees a single byte of content.

article 6 min read