A guided tool for finding the underlying cause of runtime problems—issues that occur while code runs—by pausing execution and inspecting what happens.

Use it to set breakpoints, step through code, inspect variables, and trace unexpected output back to its source.

It helps avoid guessing when tests fail, exceptions occur, programs crash or hang, or values are wrong or missing.

debug-live — Skill for Claude Code by microsoft/DebugMCP

About the project

DebugMCP is an MCP server that gives AI coding agents access to a debugger inside Visual Studio Code, including breakpoints, stepping, variable inspection, expression evaluation, and pausing execution. Developers use it to let compatible agents investigate and debug programs in any language supported by VS Code, and the catalogue includes its debugging workflow instruction and skill.

microsoft/DebugMCP · 569 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add microsoft/DebugMCP --skill debug-live

Clone the repo

git clone --depth 1 https://github.com/microsoft/DebugMCP

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/microsoft/debugmcp/debug-live/github.svg)](https://agentmods.dev/skills/microsoft/debugmcp/debug-live)

Your own site

<a href="https://agentmods.dev/skills/microsoft/debugmcp/debug-live"><img src="https://agentmods.dev/badge/skills/microsoft/debugmcp/debug-live/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/microsoft/debugmcp/debug-live"><img src="https://agentmods.dev/badge/skills/microsoft/debugmcp/debug-live.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 84 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,774 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00084	$0.02774
Opus 5.5	$0.00034	$0.01110
Sonnet 5.5	$0.00017	$0.00555
Haiku 4.5	$0.00008	$0.00277

Measured 1mo ago against content hash fca3b2a9eee0, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

debug-live scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/debug-live/SKILL.md · 277 lines

How it starts

The opening of the file, as written. The whole thing — 277 lines — stays where its author put it; the contents beside it link to each section on GitHub.

DebugMCP — Interactive Debugging Skill

This skill teaches an agent how to use the DebugMCP MCP server effectively. The MCP server itself exposes only tools (with brief, behavioral descriptions); the workflow, root cause analysis framework, and language-specific guidance live here.

The allowed-tools list above uses the tool names registered by the DebugMCP MCP server. Some runtimes namespace MCP tools (e.g. mcp__debugmcp__start_debugging); adapt as needed.

When to invoke this skill

Invoke this skill as the first investigation step whenever you would otherwise guess at runtime behavior:

Any reported bug, failing test, exception, or unexpected output.
A variable holds an unexpected null / undefined / wrong type / wrong value.
A function returns something the caller didn't expect.
A code path executes (or fails to execute) when you didn't predict it would.
You're about to read a large amount of code "trying to figure out what happens at runtime."

Core workflow

Set a starting breakpoint. Use add_breakpoint with the file path and the 1-based line number you want to pause on. Place it at the earliest point that's still relevant to the suspected issue.
Optionally add strategic breakpoints. Decision points, error-handling branches, data boundaries (where input enters, where output is produced).
Start the session. Call start_debugging with the source file path. For a single test, pass testName; the server routes through VS Code's Testing API so test runners like dotnet test / pytest / jest work correctly. The call returns when the program either hits a breakpoint (stopped) or runs to completion without pausing (terminated).
Navigate and inspect. Use step_over, step_into, step_out, continue_execution to move through code. Use pause_execution to interrupt a freely-running program (e.g. a busy loop or embedded target) when there is no breakpoint to stop at. Use list_variable_names to see what is in scope (names and types only, no values), then get_variables_values with the specific variableNames you care about, and evaluate_expression to test hypotheses live (call methods, read properties, run list comprehensions, etc.).

Read the full file on GitHub · 277 lines

Files

What ships with it

8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

1mo ago Changed · +2 lines fca3b2a9eee0
1mo ago First seen · 275 lines · 84 tokens per session scan A e6de8c2a8f51

Subscribe to this mod's changes

debug-live is a skill published in the GitHub repository microsoft/DebugMCP (569 stars, last pushed 3d ago), licensed MIT. It adds 84 tokens to every session and 2,774 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Debugging ai-agent ai-debugging breakpoints copilot cursor debugger

debug-live

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Nothing flagged

How it starts

DebugMCP — Interactive Debugging Skill

When to invoke this skill

Core workflow

What ships with it

What this file has done since we first saw it

Other skills, from other repositories

systemic-issue-triage

issue-root-resolution

rdd-defect-workflow

debug-helper

post-mortem

memorix-troubleshooting