Screenshot command fails with 'selector: Expected string, received null'

[Arrthurr]

Description

The screenshot command fails with a validation error when trying to capture a screenshot of a page.

Steps to Reproduce

agent-browser open https://example.com
agent-browser screenshot

Or with a file path:

agent-browser open https://example.com
agent-browser screenshot ./screenshot.png

Or with --full flag:

agent-browser open https://example.com
agent-browser screenshot --full ./screenshot.png

Expected Behavior

Screenshot should be captured and either output to stdout (base64) or saved to the specified file.

Actual Behavior

✗ Validation error: selector: Expected string, received null

Environment

• agent-browser version: 0.7.5
• OS: macOS (Darwin 24.6.0)
• Node version: $(node --version)

Notes

• Other commands work fine (open, snapshot, get title, get url, eval, hover, close)
• The page loads correctly and can be interacted with
• Only the screenshot command fails

[peterc]

Just installed agent-browser and have exactly the same issue. Same environment.

[peterc]

36ea8ec Seems like a fix is coming :)

[peterc]

Temporary resolution if you're not using anything new in 0.7.0: npm install -g agent-browser@0.6.0

[CarlosCommits]

It's because the "optional" selector is actually currently required. Try agent-browser screenshot "body" ./image.png and it should work.

[peterc]

Now fixed in 0.7.6 https://github.com/vercel-labs/agent-browser/releases/tag/v0.7.6