continue
Continues code execution
LABSCO SUMMARY
The state you would have had to guess at while adding console.log is readable at the moment it goes wrong.
Everything here assumes the process is already up and misbehaving: set a breakpoint by file and line, wait for the pause, then read the scope and evaluate expressions against the real values rather than the ones you predicted when you added logging. nodejs_inspect runs arbitrary JavaScript inside the debugged process, which is both what makes the tool useful and the reason to point it only at processes that are yours.
What it is
A debugger front end for a live Node.js process, exposing breakpoints, stepping, scope inspection and expression evaluation as tools.
What you get
- Breakpoints set by file and line, listed while active, and deleted by breakpointId
- Stepping once execution is paused — over, into and out — plus continue to let it run on
- The variables in the current scope and the execution location while paused
- Expressions evaluated in the current context, and JavaScript executed inside the debugged process
- The most recent console output from the process being debugged, bounded by a limit
- A manual reconnection attempt against a port when the attachment drops
Requirements
A Node.js process already running with its debugger listening on a port you can reach. These tools attach to that process; they do not start it.
Setup effort
One command — npx -y @hyperdrive-eng/mcp-nodejs-debugger
USE CASES
01
Catching a value that is only wrong sometimes
Break on the line where it goes wrong, read the whole scope at the pause, and test your theory as an expression before letting the process run on. No rebuild, no second reproduction.
02
Following a call into the code that actually fails
Step into the frame where the value changes, out again when it turns out to be somewhere else, and check the current location whenever you lose track of where the process is standing.
03
Reading what the process printed before it stopped
The recent console output of the debugged process, bounded by a limit, so the logging that is already in the code stays useful without leaving the debugging session.
04
Tidying a session that has collected too many breakpoints
List what is currently set and delete the ones by id that are no longer earning their pause. A session that stops on everything stops being a debugging session.
05
Trying a fix without restarting the process
Run the change as code inside the process that is already up, and check the result as an expression. What survives the experiment is what goes into the edit afterwards.
06
Getting back in after the connection drops
Reconnect to the debugger port by hand rather than restarting the process you were halfway through inspecting.
13 tools
Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.
delete_breakpoint
Deletes a specified breakpoint
evaluate
Evaluates a JavaScript expression in the current context
get_console_output
Gets the most recent console output from the debugged process
get_location
Gets the current execution location when paused
inspect_variables
Inspects variables in current scope
list_breakpoints
Lists all active breakpoints
nodejs_inspect
Executes JavaScript code in the debugged process
retry_connect
Manually triggers a reconnection attempt to the Node.js debugger
set_breakpoint
Sets a breakpoint at specified line and file
step_into
Steps into function calls
step_out
Steps out of current function
step_over
Steps over to the next line of code
BEFORE YOU INSTALL
What to know first
Tools you get
13 tools when we connected.
Requires
npx on PATH
CONTEXT COST
Light Standing cost
Rated by the size of the 13 tool definitions that ride along on every turn, not by how many there are
INSTALLATION
Connect your client
Add the block to your client, or run the command directly.
Server setup
Configuration file
JSON
{
"mcpServers": {
"mcp-nodejs-debugger": {
"command": "npx",
"args": [
"-y",
"@hyperdrive-eng/mcp-nodejs-debugger"
]
}
}
}npx
TERMINAL
npx -y @hyperdrive-eng/mcp-nodejs-debugger
