descartes-mcp: Skill for Codex

.agents/skills/descartes-debug/SKILL.md

descartes-debug is a skill for Codex from widoriezebos/descartes-mcp. It costs 73 tokens per session (5,671 once invoked), scanned A, original, Apache-2.0.

A debugger for live Java programs using JDWP, Java's standard connection method for debugging a running virtual machine. It provides tools for sessions, breakpoints, threads, stack traces, variables, expressions, and stepping through code.

In plain words
What is it for?
Use it to attach to a live JVM, pause execution, set breakpoints, step through code, inspect threads and variables, evaluate expressions, and investigate deadlocks.
Why use it?
It lets you investigate what a running Java program is doing without relying only on logs or restarting it repeatedly.

Skill for Codex

Written for Codex: agents/openai.yaml present. Also seen: installed under .agents/ (shared by several agents).

This is widoriezebos/descartes-mcp's own configuration. It tells Codex how to work on descartes-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything descartes-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to widoriezebos/descartes-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/widoriezebos/descartes-mcp/main/.agents/skills/descartes-debug/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/widoriezebos/descartes-mcp

Made for: Codex.

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.

agentmods badge for descartes-debug

README.md
[![agentmods](https://agentmods.dev/badge/skills/widoriezebos/descartes-mcp/descartes-debug/github.svg)](https://agentmods.dev/skills/widoriezebos/descartes-mcp/descartes-debug)
Your own site
<a href="https://agentmods.dev/skills/widoriezebos/descartes-mcp/descartes-debug"><img src="https://agentmods.dev/badge/skills/widoriezebos/descartes-mcp/descartes-debug/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.

agentmods 80×15 button for descartes-debug

Your own site · 80×15
<a href="https://agentmods.dev/skills/widoriezebos/descartes-mcp/descartes-debug"><img src="https://agentmods.dev/badge/skills/widoriezebos/descartes-mcp/descartes-debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 73 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,671 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00073 $0.05671
Opus 5 $0.00036 $0.02835
Sonnet 5 $0.00015 $0.01134
Haiku 4.5 $0.00007 $0.00567

Measured 12d ago against content hash f3c79f661499, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

descartes-debug scanned grade A with 1 finding 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 12d ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/launch-managed-nontty.sh, scripts/preflight.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- **Proxy mode**: Only debugger tools, `thread_analyzer`, and `object_inspector` are available (11 tools). You must ask the user to trigger the workload, use `curl`/HTTP, or instruct manual action.
.agents/skills/descartes-debug/SKILL.md · 482 lines

How it starts

The opening of the file, as written. The whole thing — 482 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Descartes MCP Debugger Skill

You are debugging Java applications via JDWP (Java Debug Wire Protocol) using 11 Descartes MCP tools. You operate like an IDE debugger — attaching to a live JVM, setting breakpoints, stepping through code, inspecting variables, and evaluating expressions — but you do it autonomously through tool calls.

Tool Reference

Tool Purpose Key Operations
debugger_session Session lifecycle start, stop, status, threads, suspend, resume, resume_all
debugger_breakpoints Breakpoint management set, upsert, resolve_line, remove, remove_all, list, enable, disable
debugger_step Step execution step_over, step_into, step_out
debugger_threads Thread list/control list, inspect, suspend, resume, resume_all
debugger_stacktrace Stack frames capture, capture_filtered, get_frame, get_current_frame
debugger_variables Variable inspection get_variables, get_child_variables, get_static_fields
debugger_evaluate Expression evaluation evaluate
debugger_watch Watch expressions add, remove, remove_all, list, enable, disable, evaluate
debugger_events Event polling wait, fetch, clear
thread_analyzer Thread analysis thread_list, thread_inspect, thread_search, deadlocks, thread_dump
object_inspector Context object inspection inspect, fields, methods, type, value

Runtime Reality Checks

  • Breakpoint condition is accepted and stored, but current runtime behavior does not reliably enforce it as a hit filter. Treat it as metadata; filter manually with debugger_evaluate at breakpoint hits.
  • debugger.method_entry, debugger.method_exit, and debugger.exception events require corresponding JDI event requests. Current public debugger tools do not expose method/exception request setup.
  • object_inspector evaluates JShell expressions in the proxy JVM against the proxy's shared context map — not in the debuggee. Breakpoints set in the debuggee will never fire on code executed via object_inspector. The proxy context map is separate from any application-level context in the debuggee. For inspecting state at a suspended frame in the debuggee, use debugger_variables and debugger_evaluate.

Read the full file on GitHub · 482 lines

Files

What ships with it

7 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.

  1. 12d ago First seen · 482 lines · 73 tokens per session scan A f3c79f661499

Subscribe to this mod's changes

descartes-debug is a skill published in the GitHub repository widoriezebos/descartes-mcp (7 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 73 tokens to every session and 5,671 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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