docs: Brave / Chromium 144+ fixed-port connection notes

[xBajci]

Adds a section to interaction-skills/connection.md covering connecting to Brave (and any Chromium 144+) when remote debugging is enabled via the settings checkbox on a fixed port:

• /json/version and /json/list return 404 on these builds — an empty curl is not a dead port
• read the ws path from DevToolsActivePort in the Brave profile dir
• connect with BU_NAME + BU_CDP_WS override
• stale-socket recovery for the named daemon, and the note that the browser uuid changes on every restart

Field-tested today against Brave on macOS.

🤖 Generated with Claude Code

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Summary by cubic

Add connection notes for Brave and Chromium 144+ when remote debugging is enabled on a fixed port. Covers 404 discovery endpoints, reading the websocket path from DevToolsActivePort, connecting via BU_NAME + BU_CDP_WS, handling stale sockets, and noting the browser UUID changes on each restart.

^{Written for commit 147d30b. Summary will update on new commits.}

[browser-harness-review]

✅ Skill review passed

Reviewed 1 file(s) — no findings.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds guidance for connecting to Brave’s remote debugging endpoint when the usual CDP HTTP discovery endpoints return 404, documenting how to retrieve the WebSocket path from DevToolsActivePort.

Changes:

• Document Brave/Chromium behavior where /json/version and /json/list return 404 despite CDP being available.
• Add steps to read DevToolsActivePort and connect using an explicit WebSocket URL and a dedicated daemon namespace.
• Add a note about clearing stale daemon socket/pid files on initial connection errors.

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[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="interaction-skills/connection.md">

<violation number="1" location="interaction-skills/connection.md:37">
P2: The documentation instructs users to read `DevToolsActivePort` where "line 1: port", implying the port may vary, but the connection example hardcodes `9222` in the WebSocket URL. Either clarify that the settings checkbox always binds to port 9222 (and only the UUID needs to be read), or update the example to use the port value from `DevToolsActivePort` for consistency.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Fix all with cubic | Re-trigger cubic</sub>

[cubic-dev-ai]

P2: The documentation instructs users to read DevToolsActivePort where "line 1: port", implying the port may vary, but the connection example hardcodes 9222 in the WebSocket URL. Either clarify that the settings checkbox always binds to port 9222 (and only the UUID needs to be read), or update the example to use the port value from DevToolsActivePort for consistency.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At interaction-skills/connection.md, line 37:

<comment>The documentation instructs users to read `DevToolsActivePort` where "line 1: port", implying the port may vary, but the connection example hardcodes `9222` in the WebSocket URL. Either clarify that the settings checkbox always binds to port 9222 (and only the UUID needs to be read), or update the example to use the port value from `DevToolsActivePort` for consistency.</comment>

<file context>
@@ -28,6 +28,25 @@ for t in tabs:
+
+```bash
+cat "$HOME/Library/Application Support/BraveSoftware/Brave-Browser/DevToolsActivePort"
+# line 1: port, line 2: /devtools/browser/<uuid>
+```
+
</file context>

Suggested change

	# line 1: port, line 2: /devtools/browser/<uuid>
	# line 1: port (always 9222 when using the settings checkbox), line 2: /devtools/browser/<uuid>