> ## Documentation Index > Fetch the complete documentation index at: https://docs.cortex.foundation/llms.txt > Use this file to discover all available pages before exploring further. # Origin check > Attach a photo or a clip and ask whether it is authentic. Cortex answers with one of three verdicts, or says plainly that the check could not run. **Check origin** answers one question about a photo or a clip you attach: does it read as something a camera took, or as something that was generated? It is always an explicit ask on media you attach in **Cortex Chat**. Nothing is checked silently, and a picture Cortex generated for you is not labelled automatically. This page covers running a check, reading the verdict and the figures beside it, what Content Credentials add, the file sizes and formats the check accepts, and the difference between a check that failed and one that could not run at all. ## Run a check In the composer's attach menu choose **Check origin** and pick the file. Attaching the file the ordinary way and asking whether it is real, AI-generated or a deepfake works just as well. The card shows `Checking origin…`. Cortex holds the rest of its reply until the verdict resolves, so you never get a confident paragraph followed by a result that contradicts it. The finished card carries the verdict, the figures behind it, whether the file arrived with Content Credentials, and a credit for the service that performed the check. ## Reading the verdict There are exactly three verdicts, and the middle ground is one of them rather than a rounded guess. | Verdict | What it means | | ------------------------------- | ------------------------------------------------------------------------------------------------ | | `Likely a camera photo` | The detector did not call it AI, and its confidence sits below 0.40. | | `Likely AI-generated` | The detector called it AI, with confidence above 0.70. | | `Couldn't tell with confidence` | Everything else. The file was analysed, and the result is not strong enough to claim either way. | Under the verdict, the card prints the AI likelihood as a percentage and a similarity figure, as `AI likelihood {percent}% · Similarity {similarity}`. The card also reports whether the file carried **Content Credentials**, the provenance information some cameras and editing tools attach to a file. Where there are none, it says `No Content Credentials attached.`, which is not itself a verdict: plenty of genuine photos carry no credentials. Credentials are read from the original file you attached, before Cortex compresses it for the check. A verdict is about the file, not about the world. `Likely a camera photo` says the image looks camera-made; it does not vouch for what the picture claims to show, where it was taken, or when. ## What the check accepts | Item | Limit | | ----------------- | -------------------------------------------------------------------------------------------------------------- | | Maximum file size | 10 MB per file, the same ceiling that applies to any upload in Chat, whatever your plan. | | Photos | The usual image formats Chat accepts, plus HEIC and HEIF. | | Clips | Short video within the same 10 MB ceiling. | | Allowance | There is no origin-check allowance. A check spends neither your image allowance nor your web-search allowance. | iPhone HEIC and HEIF photos are a deliberate exception: the ordinary image picker in Chat does not take them, but **Check origin** does. If you meet the hint `HEIC photos can be checked for origin. Use Check origin, or convert to JPEG or PNG.`, that is the product telling you which path to use. A file larger than the ceiling is refused when it is attached, so there is never anything for the check to read. See [`payload_too_large`](/problems/payload_too_large) and [Attachments and files](/chat/attachments). ## When the check cannot run The wording on the card tells you which of three different things happened, and all three mean no verdict rather than a weak one. | Card | What it means | What to do | | ------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------ | | `The origin check couldn't run.` with `Your image wasn't analyzed.` | The check was attempted and the file was rejected, for example because it was too large for the detector. A code and request id are printed beside it. | Use **Retry**, which re-sends the same file, or try a smaller or differently encoded copy. | | `Origin detection is temporarily unavailable.` | Origin detection is not set up on this deployment. Nothing was analysed. | Ask again later. There is nothing to fix on your side. | | `The origin check didn't finish.` | The request did not complete, typically a network problem between you and Cortex. | Retry the turn. | Cortex fails closed here on purpose. No verdict is still no verdict, and silence is never to be read as a result. ## What origin check is not | It is | It is not | | ---------------------------------------------- | -------------------------------------------------- | | A check on media **you** attach and ask about. | An automatic label on every generated picture. | | A Cortex Chat turn. | A Cortex Code tool or a Cortex Bot skill. | | A judgement about how the file was made. | A judgement about whether the scene in it is true. | Pictures made with [image generation](/chat/image-generation) are ordinary Library files. To know whether one of them reads as generated, attach it and ask, the same as any other file. ## Related * [Image generation](/chat/image-generation) creates pictures; origin check is the separate question. * [Attachments and files](/chat/attachments) covers what a turn accepts and the size ceiling. * [Library](/chat/library) is where attached and generated media are kept. * [Built-in tools](/chat/tools) lists the tools a Chat turn can call. * [Chat troubleshooting](/chat/troubleshooting) covers turns that end without a result.