hubcap block

Block network requests matching URL patterns.

When to use

Block network requests that match one or more URL patterns, such as ads, tracking scripts, or specific resource types. Use --disable to remove all active block rules. Use intercept instead if you need to modify request or response content rather than simply blocking.

Usage

hubcap block <pattern>... [--disable]

Arguments

Argument	Type	Required	Description
`pattern`	string	Yes	One or more URL patterns to block. Supports `*` wildcards.

Flags

Flag	Type	Default	Description
`--disable`	bool	`false`	Disable URL blocking and remove all block rules

Output

Field	Type	Description
`enabled`	boolean	Whether blocking is active
`patterns`	string[]	List of active block patterns (when enabled)

When rules are set:

{"enabled":true,"patterns":["*.css","*.png"]}

When disabled:

{"enabled":false}

Errors

Condition	Exit code	Stderr
No patterns provided and `--disable` not set	1	`usage: hubcap block <pattern>... [--disable]`
Chrome not connected	2	`error: connecting to Chrome: ...`
Timeout	3	`error: timeout`

Examples

Block ad and tracking requests:

hubcap block "*ads*" "*tracking*" "*analytics*"

Block all CSS and image files:

hubcap block "*.css" "*.png" "*.jpg"

Remove all block rules:

hubcap block --disable

Block third-party scripts, then take a screenshot to measure visual impact:

hubcap block "*cdn.third-party.com*" && hubcap screenshot --output page-no-thirdparty.png