What is harness-doctor?

A diagnostic tool for a Claude Code harness—the project files, permissions, and automated hooks that guide Claude while it works. It checks CLAUDE.md, settings.json, hooks, and whether the setup matches the project stack.

For checking a harness after setup, a project move, a repository clone, or a tool upgrade, then producing a scored report with fixes.

It helps explain why Claude may ignore instructions, fail to run hooks, or have unsafe or inconsistent settings.

harness-doctor — Skill for Claude Code by ShipWithAI

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 ShipWithAI/shipwithai-plugins --skill harness-doctor

Clone the repo

git clone --depth 1 https://github.com/ShipWithAI/shipwithai-plugins

Made for: Claude Code.

Or install shipwithai-harness, the plugin that ships this one along with the rest of its 2 skills.

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/shipwithai/shipwithai-plugins/harness-doctor/github.svg)](https://agentmods.dev/skills/shipwithai/shipwithai-plugins/harness-doctor)

Your own site

<a href="https://agentmods.dev/skills/shipwithai/shipwithai-plugins/harness-doctor"><img src="https://agentmods.dev/badge/skills/shipwithai/shipwithai-plugins/harness-doctor/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/shipwithai/shipwithai-plugins/harness-doctor"><img src="https://agentmods.dev/badge/skills/shipwithai/shipwithai-plugins/harness-doctor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 715 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.

Model	Per session	Once invoked
Fable 5.1	$0.00045	$0.00715
Opus 5.5	$0.00018	$0.00286
Sonnet 5.5	$0.00009	$0.00143
Haiku 4.5	$0.00005	$0.00072

Measured 2mo ago against content hash 8805162f2dcc, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

harness-doctor 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 2mo 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.

Makes network callslowCapability

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

| **Permission** | .claude/settings.json exists, valid JSON, has deny block, curl/npx not hard-denied |

plugins/harness/skills/harness-doctor/SKILL.md · 89 lines

How it starts

The opening of the file, as written. The whole thing — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Harness Doctor

Diagnostic tool for existing Claude Code harness setups. Detects missing files, misconfigured permissions, broken hook wiring, and stack mismatches. Produces a scored health report with actionable fixes.

When to Use

After running harness-setup — final validation
Harness seems to not be working (Claude ignoring CLAUDE.md or hooks)
After moving a project or cloning a repo — check hooks are executable
Periodic health check

Step 1: Detect Stack (SILENT)

Run same detection as harness-setup Step 0. Same token auto-fill logic.

Show scan summary before proceeding:

🔍 Harness Doctor — Scanning project...

Stack:    Next.js (Next.js 14.2.18)
Detected: CLAUDE.md ✓  settings.json ✓  hooks/ ✓

Step 2: Run Diagnostic Checks

Run all 4 categories unless $ARGUMENTS specifies one. Read references/doctor-checks.md for full check details per category.

Category	Key checks
Memory	CLAUDE.md exists, < 200 lines, no unfilled {{TOKEN}}, Last verified < 90 days old
Permission	.claude/settings.json exists, valid JSON, has deny block, curl/npx not hard-denied
Hooks	validate-command.py + protect-files.py exist, executable, wired in settings.json
Stack	detected stack matches CLAUDE.md stack line, commands exist in project

Step 3: Health Report

╔══════════════════════════════════════════════════╗
║        🛡️ Harness Doctor — Health Report          ║
╠══════════════════════════════════════════════════╣
║ Stack:   Next.js                                 ║
║ Score:   11/12 checks passed                     ║
╚══════════════════════════════════════════════════╝

Category          Status    Issues
──────────────────────────────────
1. Memory           ✅       0
2. Permission       ⚠️        1 warning
3. Hooks            ❌       1 critical
4. Stack            ✅       0

──── CRITICAL ────────────────────

❌ .claude/hooks/validate-command.py not executable
   Fix: chmod +x .claude/hooks/validate-command.py

──── WARNINGS ────────────────────

⚠️  CLAUDE.md Last verified: 2026-01-15 (114 days ago)
   Recommendation: Review and update to reflect current project state

Read the full file on GitHub · 89 lines

Files

What ships with it

2 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.

2mo ago First seen · 89 lines · 45 tokens per session scan A 8805162f2dcc

Subscribe to this mod's changes

harness-doctor is a skill published in the GitHub repository ShipWithAI/shipwithai-plugins (9 stars, last pushed 2mo ago), licensed MIT. It adds 45 tokens to every session and 715 once invoked, about $0.0002 per session on Opus 5.5. 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.

Building agents Claude Code Debugging ai-coding claude-code-plugin developer-tools shipwithai

harness-doctor next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
harness-doctorShipWithAI/shipwithai-plugins	Skill	9	2mo ago	MIT	A	45	Claude Code
debuggerclaude-world/director-mode-lite	Skill	80	20d ago	MIT	A	56	Claude Code
mcp-checkclaude-world/director-mode-lite	Skill	80	20d ago	MIT	A	36	Claude Code
project-health-checkclaude-world/director-mode-lite	Skill	80	20d ago	MIT	A	57	Claude Code
mobile-flows-maestrojohnkozaris/jko-claude-plugins	Skill	11	4d ago	MIT	A	102	Claude Code
debuggreglas75/zuvo	Skill	7	7d ago	MIT	A	55	Claude Code
ccc-systematic-debuggingKevinZai/commander	Skill	6	today	MIT	A	41	Claude Code

harness-doctor