X Under the Hood and Open-Source For You Code: What Creators Get

On November 3, 2026, X's @Safety account published a short post pairing two transparency pieces: the open-sourced code behind the For You feed and Under the Hood, a tool that shows eligible users data about visibility-limiting labels. X frames them as one package and says, plainly, that together they make the system inspectable. "That is the standard," the post ends.

You can read the official announcement on X. Here is what it says, what it leaves out, and what we think it means for people who post on X.

What X announced

X says that in August it open-sourced the code that affects a post's visibility in the For You feed. According to the post, that code includes ranking, model configuration, filters and core systems.

X adds three details about the repository: it is publicly available, it is updated regularly, and it accepts pull requests from outside contributors.

The second piece is Under the Hood. X says it gives eligible users aggregate data on any visibility-limiting labels applied to their account or posts, including cases driven by local legal demands.

How Under the Hood works, based on what X says

The post describes Under the Hood at a high level. The data is aggregate, which suggests summarized counts or categories rather than a post-by-post log, though X does not spell out the format. It covers labels that limit visibility, and it applies both to an account as a whole and to individual posts.

The mention of local legal demands stands out. X says Under the Hood includes cases where a label was driven by those demands, so an affected user can see that category reflected in the data.

What the post does not state: who is eligible, where to find Under the Hood in the app, or when access reaches more users. If you are unsure whether you have it, the announcement itself does not answer that.

Who this is for

X does not name a specific audience beyond "eligible users" for Under the Hood. The open-source repository, by X's description, is open to anyone, and outside contributors can submit changes for review.

In practice, two groups are likely to care most: creators and brands who depend on For You reach, and developers or researchers who want to read how ranking and filtering are built.

What it means for creators (our take)

This is our interpretation, not a claim about how X ranks posts.

The useful shift is diagnostic. When a post underperforms, the usual instinct is to guess. If you are eligible for Under the Hood, you now have a first place to check whether a visibility-limiting label was applied at all. That separates two very different problems: a label on your account or post, or content that simply did not land.

If there is no label, look at the post itself. Compare it against your past results with our engagement rate calculator to see whether it was really an outlier. Keeping copies of your best-performing posts helps too; the tweet downloader lets you archive them for reference.

For technical creators, the repository is a reading resource. Reading code is not the same as predicting outcomes, so treat it as context rather than a formula.

How the post landed

As of November 4, 2026, the announcement had 38,252 views, 456 likes, 57 reposts, 59 replies, 12 quotes and 188 bookmarks, posted from an account with about 3.16 million followers. The bookmark count is notable relative to likes, a sign that people saved it to come back to.

The bottom line

X says the For You visibility code is public and that Under the Hood shows eligible users aggregate data on labels limiting their reach. Eligibility and access details are not stated. If you have it, check it before you change your strategy.