COMMAND

The COMMAND family provides RESP2 introspection: redis-cli, cluster-aware clients, and monitoring tools use it during the handshake to discover which commands the server supports, their arity, key positions, and ACL categories. The table is static because Tellstone’s command set is fixed at build time.

COMMAND is RESP-only — the binary protocol carries its own wire encoding and does not expose this surface.

Note

Connections need the COMMAND permission (granted by the login category) to reach this handler. A limited role without the COMMAND bit is denied with -NOPERM.

COMMAND (bare)

COMMAND

Returns the details of every command, identical to COMMAND INFO with no names. Clients cache this reply for key-position routing.

Reply: an array of 10-element arrays, one per command:

1. Command name (lowercase; subcommands use parent|sub notation)
2. Arity (negative = minimum argument count, including the command name)
3. Flags (readonly, write, admin, noscript, loading, stale, fast, denyoom)
4. First key position (0 = keyless)
5. Last key position (-1 = until end of arguments)
6. Key step (increment between successive key arguments)
7. ACL categories (@read, @write, @admin, etc.)
8. Tips (empty array)
9. Key specifications (begin_search + find_keys for keyed commands)
10. Subcommands (recursive 10-element arrays)

> COMMAND
1) 1) "acl"
   2) (integer) -2
   3) 1) "admin"
      2) "noscript"
      3) "loading"
      4) "stale"
   4) (integer) 0
   5) (integer) 0
   6) (integer) 0
   7) 1) "@admin"
      2) "@slow"
      3) "@dangerous"
   8) (empty array)
   9) (empty array)
  10) 1) 1) "acl|setuser"
         ...

COMMAND COUNT

COMMAND COUNT

Returns the number of top-level commands. This deliberately matches the number of entries COMMAND (bare) returns; subcommands are counted by client-side tools.

Reply: integer.

> COMMAND COUNT
(integer) 10

COMMAND INFO

COMMAND INFO [command-name ...]

Returns a detail array for each named command. Unknown names return a null bulk reply. No names means every command (same as bare COMMAND).

Subcommands are referenced with parent|sub notation (e.g. role|create, command|count).

Reply: an array of 10-element arrays (same structure as bare COMMAND).

> COMMAND INFO get set del
1) 1) "get"
   2) (integer) 2
   3) 1) "readonly"
      2) "fast"
   4) (integer) 1
   5) (integer) 1
   6) (integer) 1
   7) 1) "@read"
      2) "@fast"
      3) "@string"
   8) (empty array)
   9) 1) 1) "flags"
         2) 1) "RO"
            2) "access"
         ...
  10) (empty array)
2) 1) "set"
   ...
3) 1) "del"
   ...

COMMAND DOCS

COMMAND DOCS [command-name ...]

Returns documentary information: summary, introduction version, functional group, and time complexity. The reply is a RESP2 flattened map — alternating name and metadata array.

Subcommands appear under parent|sub names. Unknown names are omitted (matching Valkey).

Reply: an array of [name, [field, value, ...]] pairs.

> COMMAND DOCS get
1) "get"
2) 1) "summary"
   2) "Get the value of a key"
   3) "since"
   4) "1.0.0"
   5) "group"
   6) "string"
   7) "complexity"
   8) "O(1)"

> COMMAND DOCS command
1) "command"
2) 1) "summary"
   2) "Get details about server commands"
   3) "since"
   4) "2.8.13"
   5) "group"
   6) "server"
   7) "complexity"
   8) "O(N)"
3) "command|count"
4) 1) "summary"
   2) "Return the total number of commands in the server"
   ...

COMMAND LIST

COMMAND LIST [FILTERBY MODULE <module-name> | ACLCAT <category> | PATTERN <pattern>]

Returns the sorted list of top-level command names, optionally filtered.

Without arguments, returns every command name alphabetically.

Filter types

Filter	Meaning
MODULE <name>	Commands belonging to a module. Tellstone loads no modules, so this always returns an empty list.
ACLCAT <category>	Commands in the given ACL category. Accepts @-prefixed (e.g. @read) or bare names.
PATTERN <pattern>	Commands matching a glob pattern (* = any run, ? = any single byte).

Reply: an array of bulk strings (command names).

> COMMAND LIST
1) "acl"
2) "auth"
3) "command"
4) "del"
5) "get"
6) "ping"
7) "quit"
8) "role"
9) "set"
10) "starttls"

> COMMAND LIST FILTERBY ACLCAT @read
1) "get"

> COMMAND LIST FILTERBY PATTERN s*
1) "set"
2) "starttls"

COMMAND HELP

COMMAND HELP

Prints the subcommand reference.

Reply: an array of simple strings.

> COMMAND HELP
1) "COMMAND <subcommand> [<arg> [value] [opt] ...]. Subcommands are:"
2) "COUNT"
3) "    Return the total number of commands in the server."
4) "DOCS [<command-name> ...]"
5) "    Return documentary information about commands."
6) "INFO [<command-name> ...]"
7) "    Return details about multiple commands."
8) "LIST [FILTERBY MODULE <module-name> | ACLCAT <category> | PATTERN <pattern>]"
9) "    Return a list of the server's command names."
10) "HELP"
11) "    Print this help."

ACL categories

COMMAND INFO reports each command’s ACL categories in element 7. These are derived from the RBAC catalog, so COMMAND LIST FILTERBY ACLCAT reports the real authorization model:

Category	Commands
@read	get
@write	set, del
@admin	acl, role
@connection	auth, ping, quit, starttls
@server	command
@slow	acl, role, del
@fast	auth, get, ping, quit
@string	get, set, del
@dangerous	acl, role
@noscript	acl, auth, quit, starttls
@loading	acl, auth, quit, starttls
@stale	acl, auth, quit, starttls

Error handling

• Unknown subcommand: -ERR unknown subcommand '<name>'. Try COMMAND HELP.
• Wrong arity on subcommands: -ERR wrong number of arguments for 'command|<sub>' command
• Missing RBAC permission: -NOPERM no permission for 'command' command
• Unknown FILTERBY type: -ERR unknown command list filter type '<type>'

Related

• PING — health check during the same handshake
• AUTH — authenticate before introspecting
• RBAC — the role policy behind ACL categories