diagnose

diagnose is a command for Claude Code from BitYoungjae/marketplace. It costs 15 tokens per session (851 once invoked), scanned A, original, MIT.

A command for checking a Neovim installation, its settings, key bindings, plugins, and performance. Neovim is a configurable text editor used by developers.

In plain words
What is it for?
Use it to investigate startup errors, plugin conflicts, key-binding problems, language-server issues, and performance complaints.
Why use it?
It gathers several kinds of diagnostic information in one investigation, making it easier to narrow down why the editor is failing or behaving oddly.

Command for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the nvim-doctor plugin — 3 skills, 1 command, 3 agents shipped together

Good fit Use it to investigate startup errors, plugin conflicts, key-binding problems, language-server issues, and performance complaints.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/bityoungjae/marketplace/diagnose
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.

Clone the repo
git clone --depth 1 https://github.com/BitYoungjae/marketplace

Made for: Claude Code.

Or install nvim-doctor, the plugin that ships this one along with the rest of its 3 skills, 1 command, 3 agents.

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 diagnose

README.md
[![agentmods](https://agentmods.dev/badge/commands/bityoungjae/marketplace/diagnose/github.svg)](https://agentmods.dev/commands/bityoungjae/marketplace/diagnose)
Your own site
<a href="https://agentmods.dev/commands/bityoungjae/marketplace/diagnose"><img src="https://agentmods.dev/badge/commands/bityoungjae/marketplace/diagnose/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 diagnose

Your own site · 80×15
<a href="https://agentmods.dev/commands/bityoungjae/marketplace/diagnose"><img src="https://agentmods.dev/badge/commands/bityoungjae/marketplace/diagnose.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 15 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 851 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.
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 $0.00015 $0.00851
Opus 5 $0.00008 $0.00426
Sonnet 5 $0.00003 $0.00170
Haiku 4.5 $0.00002 $0.00085

Measured 10d ago against content hash 24f3dbaabaef, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

diagnose 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 10d 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.

plugins/nvim-doctor/commands/diagnose.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

System Information

<system_info>

  • Neovim version: !nvim --version 2>&1 || echo "nvim not found"
  • Config path: !nvim --headless -c "lua print(vim.fn.stdpath('config'))" -c "qa" 2>&1 || echo "N/A"
  • Plugin count: !nvim --headless -c "lua local ok,l=pcall(require,'lazy');print(ok and #vim.tbl_keys(l.plugins()) or 'N/A')" -c "qa" 2>&1 || echo "N/A"
  • Startup time: (measured by agent during diagnosis) </system_info>

User Problem

$ARGUMENTS

Task

Step 1: Classify the Problem

Use the Classification Matrix below to determine the problem type:

Classification Keywords/Signals Primary Agent Fallback Agent
STARTUP_ERROR "E5108", "crash", "won't start", lua error stack trace nvim-diagnostician -
PLUGIN_CONFLICT "after update", specific plugin name, "conflict", "broke" plugin-investigator nvim-diagnostician
KEYMAP_ISSUE "key doesn't work", "which-key", "mapping", "leader" nvim-diagnostician config-auditor
LSP_ISSUE "LSP", "language server", "no completion", ":LspInfo" nvim-diagnostician -
PERFORMANCE "slow", "startup time", "lag", "freeze", "memory" config-auditor nvim-diagnostician
CONFIG_AUDIT "review", "audit", "deprecated", "optimize" config-auditor -
PLUGIN_VERSION "update", "version", "breaking change", "upgrade" plugin-investigator -
GENERAL unclear or multiple issues nvim-diagnostician config-auditor

Step 2: Route to Specialized Agent

Based on classification, delegate to the appropriate agent using Task:

Task(
  subagent_type="nvim-doctor:{agent-name}",
  model="{agent-model}",
  description="Diagnose: {brief-summary}",
  prompt="""
    <diagnosis_request>
      <classification>{CLASSIFICATION}</classification>
      <confidence>{HIGH|MEDIUM|LOW}</confidence>
      <user_problem>
        {original user problem from $ARGUMENTS}
      </user_problem>
      <system_info>
        {collected system info from above}
      </system_info>
    </diagnosis_request>
  """
)

Read the full file on GitHub · 85 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. 10d ago First seen · 85 lines · 15 tokens per session scan A 24f3dbaabaef

Subscribe to this mod's changes

diagnose is a command published in the GitHub repository BitYoungjae/marketplace (6 stars, last pushed 3mo ago), licensed MIT. It adds 15 tokens to every session and 851 once invoked, about $0.0001 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 2026-08-31.