blameless-postmortem

A guide for writing a blameless incident postmortem, which is a report explaining what went wrong in an outage or other incident without blaming individuals. It focuses on impact, causes in the system, and follow-up work.

In plain words
What is it for?
It is for documenting incidents, building a timeline, explaining the underlying cause with five-whys analysis, recording what worked or failed, and assigning concrete follow-ups.
Why use it?
It helps teams learn from incidents without reducing the explanation to a person's mistake. It turns vague lessons into specific actions with owners and deadlines.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/ikarusmk/aicortex/blameless-postmortem
Any agent
npx skills add IkarusMK/AIcortex --skill blameless-postmortem
Clone the repo
git clone --depth 1 https://github.com/IkarusMK/AIcortex

Made for: Claude Code, Codex.

Per session 35 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 299 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00035 $0.00299
Opus 5 $0.00017 $0.00150
Sonnet 5 $0.00007 $0.00060
Haiku 4.5 $0.00003 $0.00030

Measured 2d ago against content hash bdc3a8bfec0c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

blameless-postmortem 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 2d 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.

examples/skills/blameless-postmortem/SKILL.md · 29 lines

What it actually says

Blameless Postmortem

When to use

After any incident worth learning from (outage, data issue, security event).

Principle

Blame the system, not the person. People act reasonably given the information and tools they had. If a single human error caused an outage, the system let it.

Structure

  1. Summary — one paragraph: what broke, who was affected, how long.
  2. Impact — users/requests affected, duration, data integrity, money if any.
  3. Timeline — UTC timestamps: detection → diagnosis → mitigation → resolution.
  4. Root cause — the real underlying cause, not the trigger. Use "5 whys".
  5. What went well / what didn't — detection speed, tooling, comms.
  6. Action items — each with an owner and a due date; prefer systemic fixes (guardrails, alerts, tests) over "be more careful".

Smell tests

  • A name appears as the "cause" → reframe to the systemic gap.
  • Action items are vague ("improve monitoring") → make them concrete and owned.
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. 2d ago First seen · 29 lines · 35 tokens per session scan A bdc3a8bfec0c

Subscribe to this mod's changes

blameless-postmortem is a skill published in the GitHub repository IkarusMK/AIcortex (9 stars, last pushed 13d ago), licensed Apache-2.0. It adds 35 tokens to every session and 299 once invoked, about $0.0002 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.