# AI Context

> Queue notes, symbols and overviews, check their size against a token budget and let an agent pull them in one call.

AI Context is a queue. You put in what an agent should know before it starts: notes from a vault, symbols from a repository index, a whole index overview, skills, analyses or plans. DevHub merges them into one text. The agent takes it with one call.

## When to use it

- You know which notes or code an agent needs and do not want it to search for them.
- You start a session and want the agent to begin with the right background.

[Screenshot: The AI Context screen with a queue of items, each with its kind, owner and size in tokens, a budget indicator, a preview of the merged text and the Copy context button. The sample data shown is made up.]

## Fill the queue

Add an item with the **Context** mark or the **Add to context** button in these places: a result in [Business Context](/devhub/features/business-context/index.md), a note in the [Vault Viewer](/devhub/features/vault-viewer/index.md), an index overview or a symbol in **Projects**, and the library pages. An item already in the queue is not added twice.

When the queue is empty, the page offers **Search Business Context** and **Add from the Repository Index**.

## Order and size

1. Open **AI Context** in the sidebar.
2. Drag an item to change its place. The order of the queue is the order in the merged text.
3. Read the size: "~N tokens after merge", the raw size and what merging saved.
4. Use the remove button on an item to take it out, or **Clear queue** to empty the queue.

The size is measured against a budget, shown as "Budget N t". The default is 16,000 tokens. Change it in Settings > MCP Server, **Queue budget (tokens)**, from 1,000 to 200,000. When the queue is over the budget, the page warns you, and the warning is all it does: the queue is not blocked and an agent receives all of it.

## Preview and copy

**Show preview** displays the merged text, exactly what the `context_pull` tool returns, with the number of items and blocks. **Copy context** copies the same text, so you can paste it into any session.

## What the agent does

At the start of a task an agent calls `context_pull`. It receives the merged text with a manifest that says where each part came from, and reading it empties the queue. `context_get` returns the same text and leaves the queue as it is. Both tools are in the [catalog of DevHub tools](/devhub/reference/mcp-tools/index.md).

## Related

- [Business Context](/devhub/features/business-context/index.md)
- [Vault Viewer](/devhub/features/vault-viewer/index.md)
- [MCP server](/devhub/features/mcp-server/index.md)