Add documentation on context resolver

Author: mielvds

README.md

@@ -216,7 +216,7 @@ attempt to use a locally cached version of contexts (see
 [§ Cache JSON-LD Contexts](https://w3c.github.io/json-ld-bp/#cache-json-ld-contexts)).
 Refresh the bundled copies with `make download-bundled-contexts`.
 
-### Customizing the ContextLoader
+### Customizing the ContextResolver
 
 You can customize the way contexts are loaded and cached by passing an instance
 of `ContextResolver`. The following example implements a loader with a prefilled

docs/reference/context-resolver.md

@@ -0,0 +1,24 @@
+# :material-cached: `ContextResolver`
+
+`ContextResolver` resolves remote `@context` documents and caches the resolved
+contexts used by JSON-LD operations.
+
+::: pyld.ContextResolver
+    options:
+      show_root_heading: false
+      show_bases: false
+      heading_level: 3
+
+Pass a custom `ContextResolver` with the `contextResolver` option when you need
+to provide your own resolved-context cache or adjust the remote-context recursion
+limit. The resolver still uses a `DocumentLoader` to fetch remote context
+documents, so pass the same loader with `documentLoader`.
+
+{{ example('context_resolver.py', output_syntax='json') }}
+
+The `shared_cache` object must behave like a mutable mapping. PyLD uses
+`cachetools.LRUCache` by default, but applications can provide another mapping
+when they need a different eviction policy.
+
+Use `max_context_urls` to change how many remote contexts may be fetched while
+resolving nested or imported contexts.

docs/reference/index.md

@@ -67,6 +67,12 @@ hide: [toc]
 
     Load remote JSON-LD documents and contexts with the built-in loader classes.
 
+-   [:material-cached:{ .lg .middle } `ContextResolver`](context-resolver.md)
+
+    ---
+
+    Resolve and cache remote `@context` documents during JSON-LD processing.
+
 -   :material-hard-hat:{ .lg .middle } __In construction__
 
     ---