healthcheck

healthcheck is a skill for Claude Code, Codex from grainulation/grainulator. It costs 54 tokens per session (1,035 once invoked), scanned A, original, MIT.

A pre-flight check for the three Grainulator services: the claims engine, format converter, and knowledge store. It sends one test request to each and reports whether it responds.

In plain words
What is it for?
Use it to check service health, see which component failed, and get the exact command for fixing a failed service.
Why use it?
It shows whether the services needed for a Grainulator session are available before work begins, reducing time lost to connection problems.

Skill for Claude CodeCodex

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the grainulator plugin — 19 skills, 1 agent, 2 hooks, 4 MCP servers shipped together

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/grainulation/grainulator/healthcheck
Any agent
npx skills add grainulation/grainulator --skill healthcheck
Clone the repo
git clone --depth 1 https://github.com/grainulation/grainulator

Made for: Claude Code, Codex.

Or install grainulator, the plugin that ships this one along with the rest of its 19 skills, 1 agent, 2 hooks, 4 MCP servers.

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 healthcheck

README.md
[![agentmods](https://agentmods.dev/badge/skills/grainulation/grainulator/healthcheck.svg)](https://agentmods.dev/skills/grainulation/grainulator/healthcheck)
Your own site
<a href="https://agentmods.dev/skills/grainulation/grainulator/healthcheck"><img src="https://agentmods.dev/badge/skills/grainulation/grainulator/healthcheck.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,035 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 $0.00054 $0.01035
Opus 5 $0.00027 $0.00517
Sonnet 5 $0.00011 $0.00207
Haiku 4.5 $0.00005 $0.00103

Measured 5d ago against content hash b487122bc078, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

healthcheck 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 5d 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/healthcheck/SKILL.md · 121 lines

How it starts

The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/healthcheck -- Pre-flight MCP server verification

Fast health check for all Grainulator MCP servers. One ping per server, no retries, immediate fix commands if anything is down.

Arguments

$ARGUMENTS

Instructions

Step 1: Ping all three servers in parallel

Call these three tools simultaneously (in a single message):

  1. wheat_status — verifies the Wheat claims engine
  2. mill_formats — verifies the Mill format converter
  3. silo_list — verifies the Silo knowledge store

Step 2: Report results

Print a status table:

Grainulator Health Check
========================
  wheat  ✓ healthy   — claims engine
  mill   ✓ healthy   — format conversion
  silo   ✓ healthy   — knowledge storage

All servers operational.

If any server fails, show:

Grainulator Health Check
========================
  wheat  ✗ FAILED    — claims engine
  mill   ✓ healthy   — format conversion
  silo   ✓ healthy   — knowledge storage

Fix commands:
  wheat: claude mcp add wheat -- npx -y -p @grainulation/wheat wheat-mcp

Step 3: Diagnose failure class (only if a server failed)

Distinguish two failure types by the error message:

  1. "tool not found" or "not registered" — the MCP server is not connected. Fix: re-add it.
  2. "tool call failed" or timeout — the server is registered but the process crashed or network is down. Fix: check Node.js/network, then re-add.

Step 4: Provide fix commands

If Wheat failed:

  • Re-add: claude mcp add wheat -- npx -y -p @grainulation/wheat wheat-mcp

If Mill failed:

  • Re-add: claude mcp add mill -- npx -y @grainulation/mill serve-mcp

If Silo failed:

  • Re-add: claude mcp add silo -- npx -y @grainulation/silo serve-mcp

Step 5: Host-capability probe (Claude Code version drift)

After the three MCP pings succeed, verify the Claude Code host exposes the APIs grainulator needs. If Anthropic ships a breaking change in a minor version, this is how we detect it before the user sees silent hook failures.

Read the full file on GitHub · 121 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. 5d ago First seen · 121 lines · 54 tokens per session scan A b487122bc078

Subscribe to this mod's changes

healthcheck is a skill published in the GitHub repository grainulation/grainulator (86 stars, last pushed 4mo ago), licensed MIT. It adds 54 tokens to every session and 1,035 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.