Open QuickAdd from a URI
QuickAdd choices can be launched from external scripts or apps such as Shortcuts on Mac and iOS, through the use of the obsidian://quickadd URI.
obsidian://quickadd?choice=<YOUR_CHOICE_NAME>[&value-VALUE_NAME=...]
All parameter names and values must be properly URL encoded to work. You can use an online tool like urlencoder.org to help you easily encode parts of the URI.
The only required parameter is choice which selects the choice to run by its name. The name must match exactly, otherwise it will not be able to be found.
Variables to your choice are passed as additional value-VARIABLE_NAME parameters, with value- prefixing the name. Variables with a space in their name can still be used, but the spaces in the name must be encoded as %20 as usual. For example, a capture asking for a variable named log notes would be passed as value-log%20notes=... in the URI.
Keep in mind that unnamed variables (a bare {{VALUE}}/{{NAME}} or {{MVALUE}}) cannot be filled by the URI and you will instead be prompted inside Obsidian as usual.
Vault parameter
Like every Obsidian URI, you can use the special vault parameter to specify which vault to run QuickAdd in. If left blank, it will be executed in your most recent vault.
obsidian://quickadd?vault=My%20Vault&choice=Daily%20log&value-contents=Lorem%20ipsum.