prompt-miner

prompt-miner is a skill for Claude Code from mifunedev/openharness. It costs 153 tokens per session (3,020 once invoked), scanned A, original, Apache-2.0.

A session-analysis tool that studies past conversations between a coding agent and its user. It ranks the prompts that started those sessions and identifies prompt patterns linked to better outcomes.

In plain words
What is it for?
Use it to compare prompt styles across many sessions, find repeatable prompt patterns, and propose lessons for improving future agent instructions.
Why use it?
It replaces guesswork about which prompts work well with evidence from previous sessions. It also keeps the default analysis from exposing the original prompt text.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: reads .claude/ paths.

Good fit Use it to compare prompt styles across many sessions, find repeatable prompt patterns, and propose lessons for improving future agent instructions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mifunedev/openharness/prompt-miner
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 mifunedev/openharness --skill prompt-miner
Clone the repo
git clone --depth 1 https://github.com/mifunedev/openharness

Made for: Claude Code.

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 prompt-miner

README.md
[![agentmods](https://agentmods.dev/badge/skills/mifunedev/openharness/prompt-miner/github.svg)](https://agentmods.dev/skills/mifunedev/openharness/prompt-miner)
Your own site
<a href="https://agentmods.dev/skills/mifunedev/openharness/prompt-miner"><img src="https://agentmods.dev/badge/skills/mifunedev/openharness/prompt-miner/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 prompt-miner

Your own site · 80×15
<a href="https://agentmods.dev/skills/mifunedev/openharness/prompt-miner"><img src="https://agentmods.dev/badge/skills/mifunedev/openharness/prompt-miner.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 153 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,020 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. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Agent Snooping · line 175
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
How audits are shown
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 $0.00153 $0.03020
Opus 5 $0.00077 $0.01510
Sonnet 5 $0.00031 $0.00604
Haiku 4.5 $0.00015 $0.00302

Measured 9d ago against content hash 096b190fb352, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

prompt-miner 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.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/__tests__/mine-traces.test.mjs, scripts/mine-traces.mjs), 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.

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.

.oh/skills/prompt-miner/SKILL.md · 228 lines

How it starts

The opening of the file, as written. The whole thing — 228 lines — stays where its author put it; the contents beside it link to each section on GitHub.

prompt-miner

Mine the harness's own session history to learn which prompt traits produce the best sessions, and feed those learnings back into identity. This skill is the judgment layer on top of the deterministic mine-traces.mjs engine: the engine collects, scores, and ranks; this skill correlates prompt features against outcome, mines falsifiable markers, and proposes durable lessons for approval.

It is a cross-session, data-driven cousin of /retro. Where /retro reflects on the current conversation, /prompt-miner reflects on the corpus of past sessions across both harnesses.

disable-model-invocation: true suppresses auto-invocation only — the model will not fire this skill on its own. A user-typed /prompt-miner still runs the full body below, including the Step-3 LLM marker synthesis. There is no conflict: the deterministic engine produces an objective dataset; the LLM step interprets it.

Privacy contract

This skill reads real session transcripts, which can contain secrets and private content. The contract is non-negotiable:

  • Default output is feature vectors + metadata only — never raw prompt text. The engine omits promptText unless --include-prompt-text is passed.
  • --include-prompt-text applies a redaction pass (line-level token patterns + block-level key bodies) and prints a WARNING banner. Use it only when you must read the prompt wording, and never commit the result.
  • All artifacts land in ephemeral scratch under $TMPDIR, outside the repo. Never stage, commit, or paste a transcript or an --include-prompt-text report.
  • The engine never writes into the repository. Its only outputs are the scratch artifacts under $TMPDIR.

When to use

  • /prompt-miner invoked to mine the corpus for prompt-quality markers.
  • Periodically (the daily crons/prompt-miner.md cron drives the unattended path; this skill is the interactive path).

When NOT to use

  • /retro — reflects on the current conversation, not the historical corpus. Use /retro to close a session; use /prompt-miner to learn across sessions.
  • /audit context / /audit skills / /wiki lint — those score harness artifacts (context budget, skills, wiki). /prompt-miner scores prompts.

Read the full file on GitHub · 228 lines

Files

What ships with it

8 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. 9d ago First seen · 228 lines · 153 tokens per session scan A 096b190fb352

Subscribe to this mod's changes

prompt-miner is a skill published in the GitHub repository mifunedev/openharness (37 stars, last pushed yesterday), licensed Apache-2.0. It adds 153 tokens to every session and 3,020 once invoked, about $0.0008 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.

Related

Other skills, from other repositories

data-visualization

Use for creating publication-quality charts and multi-panel analysis summaries. Triggers when tasks involve visualizing data, plotting results, creating charts, or producing visual reports from analysis output.

langchain-ai/deepagents · 40 tokens

cuml-machine-learning

Use for GPU-accelerated machine learning on tabular data using NVIDIA cuML. Triggers when tasks involve classification, regression, clustering, dimensionality reduction, or model training on datasets.

langchain-ai/deepagents · 43 tokens

blog-post

Writes and structures long-form blog posts, creates tutorial outlines, and optimizes content for SEO with cover image generation. Use when the user asks to write a blog post, article, how-to guide, tutorial, technical writeup, thought leadership piece, or long-form content.

langchain-ai/deepagents · 58 tokens

social-media

Drafts engaging social media posts, writes hooks, suggests hashtags, creates thread structures, and generates companion images. Use when the user asks to write a LinkedIn post, tweet, Twitter/X thread, social media caption, social post, or repurpose content for social platforms.

langchain-ai/deepagents · 58 tokens

remember

Review the current conversation and capture valuable knowledge — best practices, coding conventions, architecture decisions, workflows, and user feedback — into persistent memory (AGENTS.md) or reusable skills. Use when the user says: (1) remember this, (2) save what we learned, (3) update memory, (4) capture…

langchain-ai/deepagents · 71 tokens

cudf-analytics

Use for GPU-accelerated data analysis on datasets, CSVs, or tabular data using NVIDIA cuDF. Triggers when tasks involve groupby aggregations, statistical summaries, anomaly detection, or large-scale data profiling.

langchain-ai/deepagents · 51 tokens