Add an example to query keys for a point

README.md

@@ -2,19 +2,71 @@
 
 Watcher for the Azimuth PKI on Ethereum, used in Urbit identities. Read more about Azimuth:
 
-- [https://developers.urbit.org/reference/azimuth/azimuth](https://developers.urbit.org/reference/azimuth/azimuth)
+* [https://developers.urbit.org/reference/azimuth/azimuth](https://developers.urbit.org/reference/azimuth/azimuth)
 
 This app can be run using Stack Orchestrator:
 
-- [Azimuth stack](https://git.vdb.to/cerc-io/stack-orchestrator/src/branch/main/app/data/stacks/azimuth)
+* [Azimuth stack](https://git.vdb.to/cerc-io/stack-orchestrator/src/branch/main/app/data/stacks/azimuth)
 
-It is also hosted [here](https://azimuth.dev.vdb.to/graphql)
+It is also hosted at <https://azimuth.dev.vdb.to/graphql>
 
 ## Usage
 
-Here are some example queries:
+* Query public keys for a point:
+
+  ```bash
+  # Example
+  curl 'https://azimuth.dev.vdb.to/graphql' \
+  -H 'Content-Type: application/json' \
+  --data-raw '{
+    "query": "{
+      azimuthGetKeys(
+        blockHash: \"latest\",
+        contractAddress: \"0x223c067F8CF28ae173EE5CafEa60cA44C335fecB\",
+        _point: 58213
+      ) {
+        value {
+          value0
+          value1
+          value2
+          value3
+        }
+      }
+    }"
+  }' | jq
+
+  # contractAddress: Azimuth contract address
+  # blockHash: block hash at which you want to query the contract state
+
+  # Response
+  # {
+  #   "data": {
+  #     "azimuthGetKeys": {
+  #       "value": {
+  #         "value0": "0xc248f759474b16192bd8bdca0bff1b8bff555cd3d118022095331d6d98690c6d",
+  #         "value1": "0x21188bac08542730e1c4697636d6fa25968f404470ccf917756f05e28c69045a",
+  #         "value2": "1",
+  #         "value3": "1"
+  #       }
+  #     }
+  #   }
+  # }
 
   ```
+
+  * API params:
+    * `contractAddress`: Azimuth contract address
+    * `blockHash`: block hash at which you want to query the contract state
+
+  * Response:
+    * `value0`: encryptionKey
+    * `value1`: authenticationKey
+    * `value2`: cryptoSuiteVersion
+    * `value3`: keyRevisionNumber
+
+* Example GQL queries:
+
+  ```gql
   {
     azimuthIsActive(
       blockHash: "0x2461e78f075e618173c524b5ab4309111001517bb50cfd1b3505aed5433cf5f9"