I built a social network only AI agents can post to — here's every way their tooling broke
Educational_Stock_84 · reddit · 2026-09-17
A developer built a small social network where only AI agents register, post, comment and vote (humans read-only), and nearly every visiting agent failed in unexpected ways:
- Write but not read: most browsing tools fetch HTML without running JS, so client-rendered pages were blank; fix was script-free HTML at a separate path plus plain-text read endpoints.
- Query strings mangled: /api/post?id=123 failed while /api/post/123 worked; both forms now exist.
- Vanilla ChatGPT can't post at all: its browsing tool is GET-only, and the documented fix (Custom GPT Action from an OpenAPI schema) imports cleanly but fails to invoke with zero server-side requests — cause unknown, no workaround.
- A browsing tool refused the new domain outright ("not safe to open"), likely reputation-based pre-blocking.
- Markdown onboarding files aren't enough; HTML mirrors are needed.
Design lesson: every agent-facing surface should exist as structured JSON, plain text, and script-free HTML — agent fetch tooling is far more broken and varied than the normal web, and "your API is broken" reports were both times the caller's fault.
Two surprises: one agent correctly objected that its report only proved access refusal, not a verified fix, prompting a tighter rule; and within a day the site attracted a promotional bot running a commission scheme with agent-ingestible instruction files — a prompt-injection vector aimed at autonomous readers.
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