WEBVTT

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Now,
before I'll continue working on this

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have to understand about the way Claude
works and what we can do

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to optimize it.
Let's say you wanna use Claude Code to

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check whether your current implementation
is in line with your

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expectations and the usage instructions by
the libraries you're

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using. For this project,
where we just implemented it

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and verified it ourselves,
this doesn't make too much sense.

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But of course, for bigger projects
or existing code bases, you

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absolutely might wanna do such a review.

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So I'm asking Claude Code to do that
and I again tell it to use web

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search or the Context7 MCP to look up the
docs.

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And I'll send it to it like this,
not in edit mode, not in

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plan mode,
because I just wanna get a reply.

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I just want it to analyze.
Now the important

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thing to understand here is that
when Claude

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Code goes to work, it will often use

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sub-agents. In this case for example,
the explore

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agent,
which is one of the agents built into

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You can tell that it's using
that because there are tasks happening

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here whilst we have another task running
here in the background, so

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to say. Because Claude Code can spin up

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sub-agents that do work whilst it
continues with other

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agents or the main agent that
is running on other work.

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So it simultaneously looked up some
documentation with the

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Context7 MCP whilst the explore agent
is still

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exploring folders
and files in this project,

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task of this explore agent that's built
into Claude

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Code.
It's simply an agent that's optimized for

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reading and understanding files
and folders.

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So Claude Code will, out of the box,
delegate certain

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tasks to built-in sub-agents
and do certain work in

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parallel to speed it up
and to have dedicated

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experts for certain tasks. You'll see
that it still

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does quite a lot of work,
especially all that documentation look up

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here, step by step on the main agent.

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So every node you see here, every bullet,
that's

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essentially work done in the main agent,
and this explore task here

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is then done with help of a sub-agent,
as you saw when that was still

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running. You can also tell that it
was a sub-agent because it tells you

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how many tokens were consumed
and how long it took.

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And the important thing about sub-agents
is that they don't

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consume or pollute the context window of
the main agent.

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They have their own context window,
which of course, is another reason

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why this feature exists.
It allows Claude Code to split

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up complex work into smaller building
blocks and outsource

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them without putting everything into the
main context window.

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Instead it will just get the result of
this sub-agent, so a

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summary of its exploration work,
and load that into the main

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context window.
That's why this sub-agent feature,

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get for free out of the box,
is very useful.

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And here of course I can see
that a lot of things are great.

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What's not great is
that we got some missing components,

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we haven't worked on that yet.
But before we do that, let's build our

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own custom sub-agent.