debug-microflows

A command-line method for debugging Mendix microflows and nanoflows, which are visual sequences of application actions. It can pause execution at named breakpoints and show variable values while the app runs locally.

In plain words
What is it for?
It is for setting named breakpoints, inspecting paused variables, stepping through execution, and continuing a locally running Mendix app.
Why use it?
It helps reveal where a server-side action takes the wrong branch or produces the wrong value when reading the flow alone is not enough.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/mendixlabs/mxcli/debug-microflows
Any agent
npx skills add mendixlabs/mxcli --skill debug-microflows
Clone the repo
git clone --depth 1 https://github.com/mendixlabs/mxcli

Made for: Claude Code, Codex.

Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,844 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00057 $0.01844
Opus 5 $0.00028 $0.00922
Sonnet 5 $0.00011 $0.00369
Haiku 4.5 $0.00006 $0.00184

Measured yesterday against content hash be00b36de6a7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

debug-microflows 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 yesterday.

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.

.claude/skills/mendix/debug-microflows/SKILL.md · 139 lines

How it starts

The opening of the file, as written. The whole thing — 139 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Debug Microflows — mxcli debug

Overview

mxcli debug drives the Mendix runtime's microflow debugger from the command line: set breakpoints by name, inspect a paused microflow's variables, and step/continue — against an app started by mxcli run --local. It is the headless counterpart to Studio Pro's debugger, so you can debug a server-side microflow without leaving the warm loop.

mxcli is uniquely able to offer breakpoints by name because it owns both halves: the admin password + app URL (from run --local) and the activity model GUIDs (from the .mpr). You never deal with raw GUIDs.

When to use this skill

  • A page action throws or misbehaves and you need to see where in a microflow it goes wrong, with the in-scope variables.
  • You want to confirm a microflow takes the branch/value you expect.

For a server stack trace / LOG output (not stepping), you usually just want the runtime log — see run-local (--runtime-log). Use the debugger when you need to pause and inspect live execution.

Prerequisites

  • The app running under mxcli run --local (Mendix 11.x).

  • Start it with --debug so the debugger is enabled and a session is ready:

    mxcli run --local -p app.mpr --debug
    

    --debug alone does not change runtime behaviour — nothing pauses until you set a breakpoint. It caches a debug session token under <projectDir>/.mxcli/ so the mxcli debug commands below (run from another terminal, same -p) work immediately, with no separate mxcli debug enable.

The loop

# terminal 1: app + debugger
mxcli run --local -p app.mpr --debug

# terminal 2: find the activity, break on it by name
mxcli debug activities Sudoku.ACT_Hint -p app.mpr
mxcli debug break Sudoku.ACT_Hint --activity 'Retrieve' -p app.mpr

# now trigger the microflow in the browser — the request pauses. Then:
mxcli debug paused -p app.mpr                 # which flow is paused + its variables
mxcli debug inspect Game -p app.mpr           # one variable in detail
mxcli debug step over -p app.mpr              # over | into | out
mxcli debug continue -p app.mpr               # resume (the browser request completes)

# when done — ALWAYS:
mxcli debug disable -p app.mpr

Read the full file on GitHub · 139 lines

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.

  1. yesterday First seen · 139 lines · 57 tokens per session scan A be00b36de6a7

Subscribe to this mod's changes

debug-microflows is a skill published in the GitHub repository mendixlabs/mxcli (115 stars, last pushed 2d ago), licensed Apache-2.0. It adds 57 tokens to every session and 1,844 once invoked, about $0.0003 per session on Opus 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.