# Documents and sources (/documents) Documents are source material for a chat. They are different from [outputs](/outputs): a document is something the agent reads, while an output is a versioned file the agent produces. ## Attach files to a chat Use the composer's **Tools** menu and choose **Attach files**, or type `@` in the message box to search for a file. Attached documents appear above the composer and remain available to later turns in that chat. Tidebreak copies the selected bytes into its private application data. Moving or deleting the original file later does not remove the chat's copy. To work against files that continue changing on disk, connect their folder instead; see [Connected folders](/connected-folders). ## What the agent reads At import, Tidebreak keeps the original bytes and extracts canonical text when the format supports it. The agent can list the chat's sources and read bounded ranges from them. There is no vector database or hidden semantic index: the agent reads the source directly and decides which ranges it needs. PDFs, Word documents, spreadsheets, CSV files, text, and common image formats can be opened in the document panel. A file can still be retained when text extraction is unavailable; in that case the app reports that it is not ready for text reading instead of inventing content. ## Source pills in responses When a response carries source references, Tidebreak shows a compact **Sources** row below it. The numbered pills summarize how many sources the response used. Expand the row to see the available locator for each one, such as a page, line range, sheet, or cell range. Select a source to open its document beside the conversation, at the recorded location when the format provides one. These are source shortcuts attached to the response, not a separate bibliography. Source pills point into the copy attached to that chat. They are not web links, and they do not grant the agent access to neighboring files on your machine. ## Privacy and deletion Documents and extracted text stay in the local Tidebreak profile. They are sent only to the model provider used for a turn when the agent reads them, and to another configured service only when an approved tool call requires it. Removing a document makes it unavailable to future turns in that chat. Before deleting a chat or resetting a pre-1.0 profile, export any source or output you need to keep. Work against a directory without attaching every file up front. Preview, version, restore, and export files the agent creates.