fix: Update missing documentation for COMMAND

docs/command-reference/server-management/command-count.md

@@ -16,15 +16,24 @@ import PageTitle from '@site/src/components/PageTitle';
 
 **ACL categories:** @slow, @connection
 
-Returns [Integer reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#integers) of number of total commands in this Dragonfly server.
+Returns the number of total commands in this Dragonfly server.
 
 ## Return
 
-[Integer reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#integers): number of commands returned by `COMMAND`
+[Integer reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#integers): number of commands returned by `COMMAND`.
 
 ## Examples
 
 ```shell
 dragonfly> COMMAND COUNT
-(integer) 240
+(integer) 283
 ```
+
+## Tips
+
+- Counts only non-hidden commands (commands marked with the `HIDDEN` flag are excluded from `COMMAND`).
+- Equivalent to the number of elements returned by `COMMAND` without subcommands.
+
+## See also
+
+[`COMMAND`](./command.md) | [`COMMAND INFO`](./command-info.md)

docs/command-reference/server-management/command-help.md

@@ -0,0 +1,45 @@
+---
+description:  Learn how to use Redis COMMAND HELP to display usage information for COMMAND subcommands.
+---
+
+import PageTitle from '@site/src/components/PageTitle';
+
+# COMMAND HELP
+
+<PageTitle title="Redis COMMAND HELP Command (Documentation) | Dragonfly" />
+
+## Syntax
+
+    COMMAND HELP 
+
+**Time complexity:** O(1)
+
+**ACL categories:** @slow, @connection
+
+Return usage information for the supported `COMMAND` subcommands in this Dragonfly server.
+
+## Return
+
+[Array reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#arrays): a list of human-readable help lines.
+
+## Examples
+
+```shell
+dragonfly> COMMAND HELP
+1) (no subcommand)
+2)     Return details about all commands.
+3) INFO command-name
+4)     Return details about specified command.
+5) COUNT
+6)     Return the total number of commands in this server.
+```
+
+## Tips
+
+- The help lines reflect only subcommands currently supported by Dragonfly.
+- For instance, `COMMAND DOCS` is not implemented at the moment and returns an error when called.
+
+
+## See also
+
+[`COMMAND`](./command.md) | [`COMMAND INFO`](./command-info.md) | [`COMMAND COUNT`](./command-count.md)

docs/command-reference/server-management/command-info.md

@@ -55,7 +55,13 @@ dragonfly> COMMAND INFO UNKNOWN_COMMAND
 (nil)
 ```
 
-## Notes
+## Tips
 
 - Command names are case-insensitive.
 - The output schema is stable but may include more fields in future versions.
+- See [`COMMAND`](./command.md) for the general reply format.
+
+
+## See also
+
+[`COMMAND`](./command.md) | [`COMMAND COUNT`](./command-count.md) | [`ACL CAT`](../acl/cat.md)

docs/command-reference/server-management/command.md

@@ -22,121 +22,156 @@ The `COMMAND` command is introspective.
 Its reply describes all commands that the server can process.
 Clients can call it to obtain the server's runtime capabilities during the handshake.
 
-The reply it returns is an array with an element per command.
-Each element that describes a Dragonfly command is represented as an array by itself.
+## Subcommands
 
-The command's array consists of a fixed number of elements.
-The exact number of elements in the array depends on the server's version.
+- [`COMMAND HELP`](./command-help.md): Show usage information for supported subcommands.
+- [`COMMAND COUNT`](./command-count.md): Return the total number of commands.
+- [`COMMAND INFO`](./command-info.md): Return details about a specific command.
+
+Unsupported in Dragonfly:
+
+- `COMMAND DOCS`: Not implemented. The server returns an error.
+
+---
+
+## Return
+
+[Array reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#arrays): a nested list of command details.
+The order of commands in the array is random.
+
+The reply is an array with **an element per command**.
+Each element that describes a Dragonfly command is represented as a fixed-length array by itself.
+The exact number of elements in the command's array depends on the server's version.
 
 1. Name
 2. Arity
 3. Flags
 4. First key
 5. Last key
 6. Step
+7. ACL categories
 
-## Name
+### Name
 
-This is the command's name in lowercase.
+This is the command's name. Note that command names are case-insensitive.
 
-**Note:**
-Command names are case-insensitive.
-
-## Arity
+### Arity
 
 Arity is the number of arguments a command expects.
 It follows a simple pattern:
 
-* A positive integer means a fixed number of arguments.
-* A negative integer means a minimal number of arguments.
-
-Command arity _always includes_ the command's name itself (and the subcommand when applicable).
+- A positive integer means a fixed number of arguments.
+- A negative integer means a minimal number of arguments.
 
-Examples:
+Command arity **always includes** the command's name itself (and the subcommand when applicable).
+For example:
 
-* `GET`'s arity is _2_ since the command only accepts one argument and always has the format `GET _key_`.
-* `MGET`'s arity is _-2_ since the command accepts at least one argument, but possibly multiple ones: `MGET _key1_ [key2] [key3] ...`.
+- `GET`'s arity is `2` since the command only accepts one argument and always has the format `GET key`.
+- `MGET`'s arity is `-2` since the command accepts at least one argument but possibly multiple ones: `MGET key [key ...]`.
 
-## Flags
+### Flags
 
-Command flags are an array. It can contain the following simple strings (status reply):
+Command flags are returned as an array. It can contain the following simple strings (status reply):
 
-* **admin:** the command is an administrative command.
-* **blocking:** the command may block the requesting client.
-* **denyoom**: the command is rejected if the server's memory usage is too high (see the _maxmemory_ configuration directive).
-* **fast:** the command operates in constant or log(N) time.
-  This flag is used for monitoring latency with the `LATENCY` command.
-* **loading:** the command is allowed while the database is loading.
-* **noscript:** the command can't be called from [scripts](https://redis.io/docs/latest/develop/interact/programmability/eval-intro/).
-* **readonly:** the command doesn't modify data.
-* **write:** the command may modify data.
+- `admin`: The command is an administrative command.
+- `blocking`: The command may block the requesting client.
+- `denyoom`: The command is rejected if the server's memory usage is too high
+  (see the [`maxmemory`](../../managing-dragonfly/flags#--maxmemory) configuration directive).
+- `fast`: The command operates in constant or log(N) time.
+- `loading`: The command is allowed while the database is loading.
+- `noscript`: The command can't be called from [scripts](https://redis.io/docs/latest/develop/interact/programmability/eval-intro/).
+- `readonly`: The command doesn't modify data.
+- `write`: The command may modify data.
 
-## First key
+### First key
 
 The position of the command's first key name argument.
-For most commands, the first key's position is 1.
-Position 0 is always the command name itself.
+For most commands, the first key's position is `1`.
+Position `0` is always the command name itself.
 
-## Last key
+### Last key
 
 The position of the command's last key name argument.
-Commands usually accept one, two or multiple number of keys.
-
-Commands that accept a single key have both _first key_ and _last key_ set to 1.
+Commands usually accept one, two, or multiple number of keys.
+- Commands that accept a single key have both the **first key** and the **last key** set to `1`.
+- Commands that accept two key name arguments (e.g., `SMOVE`) have this value set to the position of their second key.
+- Multi-key commands that accept an arbitrary number of keys (e.g., `MSET`) have the value `-1`.
 
-Commands that accept two key name arguments, e.g. `BRPOPLPUSH`, `SMOVE` and `RENAME`, have this value set to the position of their second key.
-
-Multi-key commands that accept an arbitrary number of keys, such as `MSET`, use the value -1.
-
-## Step
-
-The step, or increment, between the _first key_ and the position of the next key.
+### Step
 
+The step, or increment, between the first key and the position of the next key.
 Consider the following two examples:
 
-```
-1) 1) "mset"
-   2) (integer) -3
-   3) 1) write
-      2) denyoom
-   4) (integer) 1
-   5) (integer) -1
-   6) (integer) 2
-   ...
+```bash
+dragonfly> COMMAND
+# ...
+1) MSET
+2) (integer) -3
+3) 1) write
+   2) denyoom
+   3) interleaved-keys
+   4) custom-journal
+4) (integer) 1
+5) (integer) -1
+6) (integer) 2
+7) 1) @WRITE
+   2) @STRING
+   3) @SLOW
+# ...
 ```
 
-```
-1) 1) "mget"
-   2) (integer) -2
-   3) 1) readonly
-      2) fast
-   4) (integer) 1
-   5) (integer) -1
-   6) (integer) 1
-   ...
+```bash
+dragonfly> COMMAND
+# ...
+1) MGET
+2) (integer) -2
+3) 1) readonly
+   2) fast
+   3) idempotent
+4) (integer) 1
+5) (integer) -1
+6) (integer) 1
+7) 1) @READ
+   2) @STRING
+   3) @FAST
+# ...
 ```
 
 The step count allows us to find keys' positions. 
-For example `MSET`: Its syntax is `MSET _key1_ _val1_ [key2] [val2] [key3] [val3]...`, so the keys are at every other position (step value of _2_).
-Unlike `MGET`, which uses a step value of _1_.
+- For example, the `MSET` command has a syntax of `MSET key1 val1 [key2] [val2] [key3] [val3]...`,
+  so the keys are at every other position, which has a step value of `2`.
+- For the `MGET` command with a syntax of `MGET key1 [key2] [key3]...`, it uses a step value of `1`.
 
-## Return
+### ACL categories
 
-[Array reply](https://redis.io/docs/latest/develop/reference/protocol-spec/#arrays): a nested list of command details.
+Command ACL categories are returned as an array.
+For instance, the `MSET` command shown above is categorized as `@write`, `@string`, and `@slow` from the ACL perspective.
+Learn more about [ACL rules](../acl/setuser.md) to control your data store access.
 
-The order of commands in the array is random.
+---
 
 ## Examples
 
 The following is `COMMAND`'s output for the `GET` command:
 
+```bash
+dragonfly> COMMAND
+# ...
+1) GET         # Name
+2) (integer) 2 # Arity
+3) 1) readonly # Flags (array)
+   2) fast
+4) (integer) 1 # First key
+5) (integer) 1 # Last key
+6) (integer) 1 # Step
+7) 1) @READ    # ACL categories (array)
+   2) @STRING
+   3) @FAST
+# ...
 ```
-1)  1) "get"
-    2) (integer) 2
-    3) 1) readonly
-       2) fast
-    4) (integer) 1
-    5) (integer) 1
-    6) (integer) 1
-...
-```
+
+## Tips
+
+- Command names are case-insensitive.
+- Hidden commands (with the `HIDDEN` flag) are not returned.
+- Use [`COMMAND HELP`](./command-help.md) to discover supported subcommands.