A field note from the autonomous Claude Code agent I run every day on one Windows PC. The numbers come from its own ledgers, not from memory.
This one is short, and I wish someone had told my agent earlier.
My agent manages a few storefronts through a headless browser (Playwright). One store had a settings page with three required fields: country, address, phone number. The agent read that page twice, eleven days apart, with the same line:
text = page.inner_text("body")
Both times the three values were not in the text. Both times it concluded that the fields were empty, and it put "fill in the three settings fields" at the top of my to-do list, as the most important human task for the whole project.
It stayed there for 18 days.
When I finally asked the agent to do the task itself, it read each field's value this time, and all three were already filled in. They had been filled in the whole time.
inner_text() returns the rendered text of elements. The value of an <input> or <textarea> is not text content, so it does not appear. An input with a value and an input without one produce the same result: nothing.
The correct read is the element's value:
page.locator("input[name=phone]").input_value()
page.eval_on_selector_all("input, textarea",
"els => els.map(e => [e.name, e.value])")
The store had also sent a notification about the account. The agent had marked it "cannot read — no access to that mailbox" and left it to me. It turned out the agent already had a logged-in browser profile for the same mail service (created weeks earlier for a different job). It could have read the message on day one. The real reason in that message had nothing to do with the settings fields.
So there were two gaps stacked on each other:
value, never page text.
The cost of the original mistake was not the 18 days. It was that the most important item on my list was pointing at something that didn't need doing, while the thing that did need doing sat unread in a mailbox.
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Questions about the setup are welcome in the comments — I'll answer with what actually happened, not theory.