Update project READMEs

Author: petehayes102

agent/README.md

@@ -1,4 +1,4 @@
-# Intecture Agent
+# Agent
 
 Intecture Agent is a tiny daemon that exposes Intecture's core API as a service. This service should be running on each of your hosts to allow Intecture to manage them remotely. To connect to a remote host, use the `host::remote::Plain` type from [core](../core/).
 

core/README.md

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+# Core API
+
+The core API contains the endpoints used to configure a host, as well as the underlying OS abstractions that they are built on. Usually you'll use Intecture Proj ([proj/](../proj/)) instead, which reexports the core API, though for some applications, the core API will suffice.
+
+## Project structure
+
+The core API is organised into a series of directories for each endpoint (e.g. `command/`, `host/` etc.). Within each endpoint is a `providers/` directory that houses the underlying abstractions.
+
+## Usage
+
+For API usage, check out the [examples](examples/).