harness-simplify

harness-simplify is a skill for Claude Code from uppifyagency/claude-harness. It costs 86 tokens per session (795 once invoked), scanned A, original, MIT.

A testing method for checking whether parts of an AI development workflow are still needed. It removes one part at a time, repeats the task, and compares the result with the full workflow.

In plain words
What is it for?
Use it to test whether feedback rounds, an evaluator, or a planner can be removed from an AI build process.
Why use it?
It helps identify workflow steps that add cost or time without improving the result. A baseline result is used for comparison when available.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: names the AskUserQuestion tool; positional $N argument.

Part of the claude-harness plugin — 4 skills, 3 agents, 1 hook shipped together

Good fit Use it to test whether feedback rounds, an evaluator, or a planner can be removed from an AI build process.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/uppifyagency/claude-harness/harness-simplify
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 uppifyagency/claude-harness --skill harness-simplify
Clone the repo
git clone --depth 1 https://github.com/uppifyagency/claude-harness

Made for: Claude Code.

Or install claude-harness, the plugin that ships this one along with the rest of its 4 skills, 3 agents, 1 hook.

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 harness-simplify

README.md
[![agentmods](https://agentmods.dev/badge/skills/uppifyagency/claude-harness/harness-simplify/github.svg)](https://agentmods.dev/skills/uppifyagency/claude-harness/harness-simplify)
Your own site
<a href="https://agentmods.dev/skills/uppifyagency/claude-harness/harness-simplify"><img src="https://agentmods.dev/badge/skills/uppifyagency/claude-harness/harness-simplify/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 harness-simplify

Your own site · 80×15
<a href="https://agentmods.dev/skills/uppifyagency/claude-harness/harness-simplify"><img src="https://agentmods.dev/badge/skills/uppifyagency/claude-harness/harness-simplify.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 86 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 795 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 $0.00086 $0.00795
Opus 5 $0.00043 $0.00398
Sonnet 5 $0.00017 $0.00159
Haiku 4.5 $0.00009 $0.00080

Measured 9d ago against content hash bca703a78f1a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

harness-simplify 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 9d 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/harness-simplify/SKILL.md · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Harness Simplify — Component Stress Testing

Overview

Every harness component encodes an assumption about what the model can't do on its own. This skill tests those assumptions by removing one component, re-running a task, and comparing quality.

"Find the simplest solution possible, and only increase complexity when needed."

Execution

Step 1: Identify Target Component

If the user specified a component, use it. Otherwise, ask which to test:

Component Assumption it encodes Cost saved if removed
evaluator Model can't judge its own work ~$3-10 per eval round + time
planner Model can't expand briefs well inline ~$0.50 + 5 min
rounds Model needs external feedback loops Proportional to rounds saved

Recommended test order: roundsevaluatorplanner (least to most impactful).

Step 2: Establish Baseline

Check for existing harness results in .harness/:

  • If a completed run exists, use its eval scores as baseline
  • If not, inform the user a baseline run is needed first

Record baseline scores:

Baseline (all components):
  Design Quality: X/5
  Originality: X/5
  Craft: X/5
  Functionality: X/5
  Cost: $X
  Time: Xm

Step 3: Run Without Component

Temporarily disable the component in .harness/config.json and dispatch a new harness run on the same brief.

  • Remove evaluator: Generator builds, no QA pass. User or simplified heuristic checks quality.
  • Remove planner: Generator works directly from user brief (no spec expansion).
  • Reduce rounds: Set maxRounds: 1 (single build + single eval).

Step 4: Compare Results

If evaluator is enabled for comparison, dispatch it on both outputs. Present side-by-side:

                    With Component    Without Component
Design Quality:     4/5               3/5
Originality:        3/5               3/5
Craft:              4/5               4/5
Functionality:      4/5               2/5
Cost:               $125              $72
Time:               3h50m             2h07m

Read the full file on GitHub · 91 lines

Files

What ships with it

1 file 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. 9d ago First seen · 91 lines · 86 tokens per session scan A bca703a78f1a

Subscribe to this mod's changes

harness-simplify is a skill published in the GitHub repository uppifyagency/claude-harness (5 stars, last pushed 5mo ago), licensed MIT. It adds 86 tokens to every session and 795 once invoked, about $0.0004 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.