harness-distill

harness-distill is a skill for Claude Code from waqas1412/claude-harness. It costs 117 tokens per session (1,262 once invoked), scanned A, original, MIT.

A read-only process for finding reusable lessons in recent coding sessions, review corrections, and recurring problems.

In plain words
What is it for?
Use it to extract candidate rules for project instructions, agent skills, or stored notes, then review those proposals before saving them.
Why use it?
It helps preserve useful lessons so the same mistakes or sources of friction are less likely to recur.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions subagents.

Part of the harness plugin — 9 skills, 16 agents, 2 hooks shipped together

Good fit Use it to extract candidate rules for project instructions, agent skills, or stored notes, then review those proposals before saving them.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/waqas1412/claude-harness/harness-distill
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 waqas1412/claude-harness --skill harness-distill
Clone the repo
git clone --depth 1 https://github.com/waqas1412/claude-harness

Made for: Claude Code.

Or install harness, the plugin that ships this one along with the rest of its 9 skills, 16 agents, 2 hooks.

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-distill

README.md
[![agentmods](https://agentmods.dev/badge/skills/waqas1412/claude-harness/harness-distill/github.svg)](https://agentmods.dev/skills/waqas1412/claude-harness/harness-distill)
Your own site
<a href="https://agentmods.dev/skills/waqas1412/claude-harness/harness-distill"><img src="https://agentmods.dev/badge/skills/waqas1412/claude-harness/harness-distill/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-distill

Your own site · 80×15
<a href="https://agentmods.dev/skills/waqas1412/claude-harness/harness-distill"><img src="https://agentmods.dev/badge/skills/waqas1412/claude-harness/harness-distill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 117 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,262 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 $0.00117 $0.01262
Opus 5 $0.00059 $0.00631
Sonnet 5 $0.00023 $0.00252
Haiku 4.5 $0.00012 $0.00126

Measured 4d ago against content hash 52c1186844ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

harness-distill 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 4d 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/harness/skills/harness-distill/SKILL.md · 84 lines

How it starts

The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/harness-distill: mine sessions into verified learning proposals

A recipe, not an engine. It closes the harness's one-directional gap: learnings from real sessions are otherwise captured only by hand. It carries no Write/Edit tool, so it is structurally propose-only: the brain plans and delegates, read-only advisors fan out, and every survivor is emitted as a proposal for your approval, never a silent mutation. On-demand only; there is no scheduler. Invoking this skill by name is the explicit in-the-moment opt-in the global single-main-loop rule requires; it licenses the fan-out described below and nothing else. The verbose rubric, skeptic prompt, dedup rule, and proposal template live in references/distill-pipeline.md, opened when a step needs them.

Scope discipline

This is a prose choreography over native subagent dispatch, like /orchestrate. Do not build a coordinator, daemon, message bus, or scheduler. Default to a tight bounded slice (the current session plus a small recent window for this repo) because mining transcripts is token-heavy; the user can widen via the argument. Use effort, not model tiers: low effort for batch extraction and clustering, high effort for the skeptic pass. Never pin a per-agent model.

Step 1: Scope and gather (read-only)

Default slice: the current session plus a small recent window of this repo's transcripts at ~/.claude/projects/<slug>/*.jsonl, plus code-review corrections (prior /code-review output and gh pr review comments). If those transcripts are absent (a fresh install), say so and stop; there is nothing to distill. Extract candidate signals with Bash plus jq over the slice; reserve a mechanical-tier haiku agent per session only for a large batch. Candidate signals: explicit user corrections, repeated friction, gotchas hit, and successful ad hoc approaches. See the extraction heuristics in references/distill-pipeline.md.

Step 2: Cluster (sonnet, parallel)

Fan out agents to group the raw candidates by theme in one pass. Recurrence across two or more sessions is the signal; a one-off is noise and drops out here.

Read the full file on GitHub · 84 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. 4d ago Changed 52c1186844ef
  2. 12d ago First seen · 84 lines · 117 tokens per session scan A ee60546cc002

Subscribe to this mod's changes

harness-distill is a skill published in the GitHub repository waqas1412/claude-harness (1 stars, last pushed 5d ago), licensed MIT. It adds 117 tokens to every session and 1,262 once invoked, about $0.0006 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.

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