VS Code Extensions
Signal - Bug debugger

Signal - Bug debugger

by catchsignal

Signal is a VS Code bug debugger that connects live browser bug sessions with your editor and AI agent, providing source navigation, debug reports, session context, and built-in MCP tools for root-cause analysis.

Downloads

21

Rating

— (0)

Version

0.1.7

Last updated

Apr 07, 2026

Jump from a live bug report straight into the right file in your editor, with full context handed to the AI agent.

Built to work with the Signal Chrome extension - install both and your AI agent gets everything it needs to find and fix bugs without you copying a single log line.

How it works

  1. Install the Signal Chrome extension and record a bug session
  2. Signal captures the full context - console errors, network traffic, framework state, user journey - and sends it to this extension
  3. VS Code opens automatically, navigates to the relevant source file, and launches the AI agent with a pre-filled prompt
  4. The agent uses the built-in MCP tools to drill into the session data on demand and find the root cause
Signal Chrome extension
  → captures session (console, network, framework state, DOM)
  → POST to bundled MCP server (auto-started by this extension)
  → open vscode://catchsignal.signal/open?workspace=...&sessionId=...
    → VS Code switches to the right workspace + file
    → Debug panel opens with the full report
    → AI agent chat opens with session summary + MCP tool access

No server to run. No configuration. Just install and record.

Requirements

That's it. The MCP server is bundled inside this extension and starts automatically when VS Code opens.

Features

  • Zero-config MCP server - bundled and auto-started on VS Code launch, registered globally in mcp.servers so every workspace can use it
  • URI handler - receives vscode://catchsignal.signal/open deep links, switches workspace if needed, resumes automatically after reload
  • File navigation - opens the source-map-resolved file at the exact line from the stack frame
  • Debug panel - side-by-side webview with detected problems, user journey, console errors (clickable, jump to source), XHR requests, storage snapshot, and framework info
  • Agent chat - pre-fills Copilot Chat with a structured prompt covering session summary, detected problems, and step-by-step MCP tool instructions

Bundled MCP tools

The MCP server starts on localhost:7744 (or the next free port) and exposes these tools to the AI agent:

Tool What the agent gets
get_session_summary 8 KB structured digest of the full session - always call this first
get_network_request Full request headers and body for any captured XHR/fetch call
get_network_response Full response headers and body - see exactly what the API returned
get_framework_state Vue/Pinia or React/Redux state at the moment the issue occurred
get_highlighted_element The DOM element the user flagged, with outerHTML, styles, actual vs expected value
get_console_event A specific console error or warning with its complete stack trace
get_storage_snapshot localStorage, sessionStorage and cookies at any point in the session
get_source_file Read a local source file with line context after resolving a stack frame
get_git_log Recent commits touching a specific file - useful for spotting recent regressions
resolve_stack_frame Map a minified stack frame to the original source line via source maps
search_codebase Grep the repo for a symbol, error message, or string

Tools are registered automatically in VS Code's global mcp.servers setting - no .vscode/mcp.json file or per-project setup needed.

Commands

Command Description
Signal: Open debug panel Re-open the debug panel for the last loaded session