Imporve the document of subAgents

[tamuratak]

vscode-docs/docs/copilot/chat/chat-sessions.md

Line 107 in c943b09

## Context-isolated Subagents

Since subAgents are a new concept, I think a more detailed explanation is needed.

1. It would be better to include the following description from the modelDescription of the subAgents tool, as information useful to the LLM is also useful to humans:

   • subAgents do not run asynchronously or in the background.

2. It would be better to add a sentence like the following after “Uses its own context window separate from the main chat session.”

   • Uses its own context window separate from the main chat session, so it does not consume the main chat session’s context window.

3. The term “research” is too broad and not specific enough for users. You should also add an example like the following:

   • For tasks such as searching and locating relevant code in a codebase, the agent avoids overwhelming the main session’s context window with large amounts of search results.

[ntrogh]

Subagents are still only in Insiders, so early preview. As the functionality evolves, we'll update the docs accordingly.

[sanjana2505006]

Hello,
I’d love to work on this issue to improve the documentation for subAgents.
I’ve gone through the discussion and the referenced file (docs/copilot/chat/chat-sessions.md) and can make the suggested edits for clarity and structure.
Could you please assign this issue to me so I can get started?

[ntrogh]

@sanjana2505006 Appreciate the support! Given this feature is still in development, the docs might still change considerably by the team.