QCS CLI Reference
This document serves as a reference for QCS CLI commands and configuration.
For a guided tour of the QCS CLI, including how to install it and configure credentials, see Using the QCS CLI.


Basic Commands


Usage: qcs help [<command>]
Display help for any specified command (or subcommand). If no command is given, this will display help for available top-level commands.
Alternately, use the -h or --h flag with any command to display help.


Usage: qcs help-config
Display CLI configuration guidance.


Usage: qcs help-input
Display guidance on formatting input to API commands.


Usage: qcs version [current|latest|update]
current: Display version information for installed CLI (default).
latest: Display version information for latest available CLI.
update: Update installed CLI to latest available version.

API Commands

Usage: qcs api [<command>]
The api commands provide a comprehensive set of ways to interact with the QCS API.
Use qcs help api and qcs help-input for full details on using API commands.
All timestamps supplied to qcs api subcommands must be in RFC3339 format. Use qcs tools format-date to format a human-friendly date as an RFC3339 timestamp.

Tool Commands

Usage: qcs tools [<command>]
The tools commands provide convenient helpers for common tasks.
See below (or use qcs help tools) for details on available commands.


Usage: qcs tools format-date <date-string>
Format a human-friendly date string as an RFC3339 timestamp, for use with API commands.
qcs tools format-date "Jan 2 15:04:05 PDT 2006"
will output:


Usage: qcs tools reserve --quantum-processor-id <id> [<options>]
List available reservations for a QPU and interactively book.
Available Options:
--duration , -d
string, default: 15m0s
Duration of reservation, specified as a sequence of positive or negative numbers, each with a time unit suffix.
Examples: 300ms, -1.5h or 2h45m
Valid time units are:
  • ns: Nanoseconds
  • us (or µs): Microseconds
  • ms: Milliseconds
  • s: Seconds
  • m: Minutes
  • h: Hours
Book the next available reservation.
Including this flag will immediately purchase the next available reservation, without additional confirmation.
Notes to add to reservation.
--quantum-processor-id, -q
string, required
ID of quantum processor to reserve.
--start-time-from, -s
string, default: current time
Time after which to search for available reservations.
For details on allowed time formats, refer to this page.

Configuration Commands

QCS CLI commands derive configuration from the environment:
Environment Variable
Default Value
  • QCS_SETTINGS_FILE (default
The settings and secrets commands provide functionality for reading and updating settings and credentials for the QCS CLI.
Use qcs help settings, qcs help secrets, and qcs help-config for full details on all available commands.
The default locations for settings and secrets are ~/.qcs/settings.toml and ~/.qcs/secrets.toml, respectively.
These locations can be overridden by setting the QCS_SETTINGS_FILE_PATHandQCS_SECRETS_FILE_PATH environment variables, respectively.