post-core-update-recovery

post-core-update-recovery is a skill for Claude Code from maxschottke-spec/seo-survival-kit. It costs 154 tokens per session (2,711 once invoked), scanned A, original, MIT.

A recovery framework for websites that lost broad search visibility after a published Google Core Update. A Core Update is a major change to Google’s ranking systems that can affect many sites and search terms at once.

In plain words
What is it for?
Use it to investigate widespread ranking and visibility drops, check related Search Console signals, and organize recovery work when pages still index normally and no manual action is present.
Why use it?
It helps separate a broad ranking decline linked to a Google update from technical problems, manual penalties, or normal fluctuations. It sets expectations that recovery may take months rather than weeks.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the seo-rescue plugin — 18 skills, 6 commands shipped together

Good fit Use it to investigate widespread ranking and visibility drops, check related Search Console signals, and organize recovery work when pages still index normally and no manual action is present.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery
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 maxschottke-spec/seo-survival-kit --skill post-core-update-recovery
Clone the repo
git clone --depth 1 https://github.com/maxschottke-spec/seo-survival-kit

Made for: Claude Code.

Or install seo-rescue, the plugin that ships this one along with the rest of its 18 skills, 6 commands.

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-core-update-recovery

README.md
[![agentmods](https://agentmods.dev/badge/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery/github.svg)](https://agentmods.dev/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery)
Your own site
<a href="https://agentmods.dev/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery"><img src="https://agentmods.dev/badge/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery/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-core-update-recovery

Your own site · 80×15
<a href="https://agentmods.dev/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery"><img src="https://agentmods.dev/badge/skills/maxschottke-spec/seo-survival-kit/post-core-update-recovery.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 154 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,711 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 $0.00154 $0.02711
Opus 5 $0.00077 $0.01355
Sonnet 5 $0.00031 $0.00542
Haiku 4.5 $0.00015 $0.00271

Measured 11d ago against content hash 85f256250df1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

post-core-update-recovery 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 11d 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/seo-rescue/skills/post-core-update-recovery/SKILL.md · 179 lines

How it starts

The opening of the file, as written. The whole thing — 179 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Post-Core-Update Recovery

Overview

A specific recovery framework for domains that lost visibility after a Google Core Update. Core insight from real March/April 2026 recovery cases: Authority items > technical hygiene. Recovery 6–12 months, not 6–8 weeks.

When to use

  • VI drop correlates timely with a published Core Update (see Google Search Status Dashboard)
  • Drop is broad (many keywords simultaneously, not pinpoint)
  • Pages keep indexing normally, no technical break
  • GSC shows no manual action
  • Pattern: 1–6 weeks of decline, then bottoming out

Don't use for:

  • Point keyword losses → usually on-page issue, not core update
  • Drop coincides with migration / theme change / robots change → that's technical, not core
  • Drop is <20 % from peak → can be normal market noise

Diagnosis decision tree

digraph diag {
    "Visibility dropped?" [shape=diamond];
    "Correlates with Core Update date?" [shape=diamond];
    "Brand keywords also dropped?" [shape=diamond];
    "Manual action in GSC?" [shape=diamond];
    "CWV suddenly red?" [shape=diamond];
    "Apply Recovery (this skill)" [shape=box,style=filled,fillcolor=lightblue];
    "Technical problem first" [shape=box,style=filled,fillcolor=lightyellow];
    "Penalty workflow, not here" [shape=box,style=filled,fillcolor=lightcoral];
    "Performance-first workflow" [shape=box,style=filled,fillcolor=lightyellow];
    "Market noise, observe" [shape=box];

    "Visibility dropped?" -> "Correlates with Core Update date?" [label="yes"];
    "Correlates with Core Update date?" -> "Manual action in GSC?" [label="yes"];
    "Manual action in GSC?" -> "Penalty workflow, not here" [label="yes"];
    "Manual action in GSC?" -> "Brand keywords also dropped?" [label="no"];
    "Brand keywords also dropped?" -> "Technical problem first" [label="yes"];
    "Brand keywords also dropped?" -> "CWV suddenly red?" [label="no"];
    "CWV suddenly red?" -> "Performance-first workflow" [label="yes"];
    "CWV suddenly red?" -> "Apply Recovery (this skill)" [label="no"];
    "Correlates with Core Update date?" -> "Market noise, observe" [label="no"];
}

Read the full file on GitHub · 179 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. 11d ago First seen · 179 lines · 154 tokens per session scan A 85f256250df1

Subscribe to this mod's changes

post-core-update-recovery is a skill published in the GitHub repository maxschottke-spec/seo-survival-kit (9 stars, last pushed 1mo ago), licensed MIT. It adds 154 tokens to every session and 2,711 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 2026-08-31.

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