docs(mcp): document ephemeral tab IDs and screenshot-after-open-browser#329
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Agents were reusing stale tab/pane IDs across session boundaries, causing 'tab not found' errors. Also, agents were not confirming that browser pages loaded successfully after open-browser, leading to silent failures (blank pages, CORS errors, network issues). Add two key gotchas to INSTRUCTIONS: - Tab and pane IDs are ephemeral — don't reuse across reconnects - Always screenshot after open-browser to confirm page load Update the open-browser playbook to include a screenshot step, and add confirmation guidance to the screenshot section.
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Summary
Agents using the Freshell MCP tool were hitting two avoidable pitfalls:
Stale tab/pane IDs — IDs from
open-browser,new-tab, andsplit-panebecome invalid after server restarts or session reconnects. Agents were reusing old IDs, causing "tab not found" errors.Silent browser failures — After
open-browser, agents assumed the page loaded successfully. Network errors, CORS issues, and blank pages went undetected because no screenshot was taken to confirm.Changes
Three places in
server/mcp/freshell-tool.ts(all documentation/template strings, no code logic):screenshotcall afteropen-browsershowing the exact commandTest plan