post-mortems-retrospectives

post-mortems-retrospectives is a skill for Claude Code, Codex from liqiongyu/lenny_skills_plus. It costs 28 tokens per session (2,159 once invoked), scanned A, original, Apache-2.0.

A guide for reviewing incidents, projects, or goals after the work is over, without blaming individuals. It turns a timeline of events into lessons, decisions, and tracked follow-up work.

In plain words
What is it for?
Use it for incident post-mortems, project or OKR retrospectives, after-action reviews, pre-mortems, action owners and due dates, success measures, and conditions for changing or stopping a plan.
Why use it?
It helps teams understand system causes and missed goals instead of stopping at a description of what went wrong. It also keeps agreed actions from being forgotten.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it for incident post-mortems, project or OKR retrospectives, after-action reviews, pre-mortems, action owners and due dates, success measures, and conditions for changing or stopping a plan.

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Install with agentmods
npx agentmods add skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives
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 liqiongyu/lenny_skills_plus --skill post-mortems-retrospectives
Clone the repo
git clone --depth 1 https://github.com/liqiongyu/lenny_skills_plus

Made for: Claude Code, Codex.

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 post-mortems-retrospectives

README.md
[![agentmods](https://agentmods.dev/badge/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives/github.svg)](https://agentmods.dev/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives)
Your own site
<a href="https://agentmods.dev/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives"><img src="https://agentmods.dev/badge/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives/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 post-mortems-retrospectives

Your own site · 80×15
<a href="https://agentmods.dev/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives"><img src="https://agentmods.dev/badge/skills/liqiongyu/lenny_skills_plus/post-mortems-retrospectives.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,159 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 $0.00028 $0.02159
Opus 5 $0.00014 $0.01079
Sonnet 5 $0.00006 $0.00432
Haiku 4.5 $0.00003 $0.00216

Measured 12d ago against content hash bf300fccd18c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

post-mortems-retrospectives 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 12d 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/post-mortems-retrospectives/SKILL.md · 134 lines

How it starts

The opening of the file, as written. The whole thing — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Post-mortems & Retrospectives

Scope

Covers

  • Running blameless incident post-mortems and project/OKR retrospectives
  • Turning "what happened?" into system learnings + decisions (not blame)
  • Creating follow-through: owners, due dates, success signals, and review cadence
  • Adding kill criteria / triggers so future pre-mortems lead to real action
  • Institutionalizing learning via a lightweight "Impact & Learnings" review

When to use

  • "Run a postmortem / retrospective for <incident/project> and write the doc."
  • "We missed OKRs—lead a retro focused on learning and systemic blockers."
  • "Create an after-action review with action items and owners."
  • "Set up a weekly impact & learnings review so insights don't die in docs."
  • "Do a pre-mortem and define kill criteria / pivot triggers."

When NOT to use

  • The incident is still active (do incident response first; schedule the review after stabilization)
  • The goal is to assign blame or evaluate an individual's performance (use HR/management processes)
  • You need deep technical debugging without the right experts (this skill facilitates; it doesn't replace engineering investigation)
  • You need to decide what problem to solve (use a problem-definition / discovery process first)
  • You need to facilitate a meeting that is not a post-mortem or retrospective (use running-effective-meetings)
  • You need to improve the shipping process itself, not review a past launch (use shipping-products)
  • You need to change engineering culture or practices based on systemic patterns across retros (use engineering-culture)
  • You need to plan for future risks and uncertainties rather than review past events (use planning-under-uncertainty)

Inputs

Minimum required

  • What are we reviewing? (incident / project / OKR period) + 1–2 sentence summary
  • Time window and key dates (start/end; detection time; resolution time if incident)
  • Desired outcome (learning, prevention, speed, quality, alignment)
  • Participants/roles (facilitator, scribe, decision owner; key stakeholders)
  • Evidence available (timeline notes, metrics, dashboards, tickets, docs)
  • Constraints (privacy; what to anonymize; audience)

Read the full file on GitHub · 134 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. 12d ago First seen · 134 lines · 28 tokens per session scan A bf300fccd18c

Subscribe to this mod's changes

post-mortems-retrospectives is a skill published in the GitHub repository liqiongyu/lenny_skills_plus (52 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 28 tokens to every session and 2,159 once invoked, about $0.0001 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.