migrate-from-legacy

migrate-from-legacy is a skill for Claude Code from haabe/mycelium. It costs 86 tokens per session (2,817 once invoked), scanned A, original, MIT.

A migration guide for moving a Mycelium project from an older local installation to the newer plugin-based installation. Project state stays in the project while framework files move into the plugin cache.

In plain words
What is it for?
Use it to detect the current installation type, migrate legacy files, preserve project state, and confirm that the plugin is installed.
Why use it?
It avoids losing canvases, decisions, evaluations, metrics, and other project data during the change. It also checks whether migration is needed and verifies the result.

Skill for Claude Code

Written for Claude Code: $CLAUDE_PROJECT_DIR variable. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions Claude Code.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the mycelium plugin — 61 skills, 6 hooks shipped together

Good fit Use it to detect the current installation type, migrate legacy files, preserve project state, and confirm that the plugin is installed.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add haabe/mycelium
Claude Code
/plugin install mycelium

Made for: Claude Code.

Or install mycelium, the plugin that ships this one along with the rest of its 61 skills, 6 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 migrate-from-legacy

README.md
[![agentmods](https://agentmods.dev/badge/skills/haabe/mycelium/migrate-from-legacy/github.svg)](https://agentmods.dev/skills/haabe/mycelium/migrate-from-legacy)
Your own site
<a href="https://agentmods.dev/skills/haabe/mycelium/migrate-from-legacy"><img src="https://agentmods.dev/badge/skills/haabe/mycelium/migrate-from-legacy/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 migrate-from-legacy

Your own site · 80×15
<a href="https://agentmods.dev/skills/haabe/mycelium/migrate-from-legacy"><img src="https://agentmods.dev/badge/skills/haabe/mycelium/migrate-from-legacy.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 86 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,817 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 $0.00086 $0.02817
Opus 5 $0.00043 $0.01409
Sonnet 5 $0.00017 $0.00563
Haiku 4.5 $0.00009 $0.00282

Measured 9d ago against content hash 45025a35cb9f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

migrate-from-legacy 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.

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/mycelium/skills/migrate-from-legacy/SKILL.md · 201 lines

How it starts

The opening of the file, as written. The whole thing — 201 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Migrate from legacy to plugin form

When this skill runs, walk the user through moving from legacy install to plugin install. The migration is non-destructive to project state: canvas, diamonds, memory, decision log, evals, and active metrics are preserved. Only framework reference content (skills, hooks, engine, scripts, schemas, etc.) is removed from .claude/ — that content now ships in the plugin cache.

Step 1: Detect current install form

Check the project's .claude/ directory:

test -d "$CLAUDE_PROJECT_DIR/.claude/skills" && echo "legacy framework files present" || echo "no legacy framework files"
test -d "$CLAUDE_PROJECT_DIR/.claude/canvas" && echo "project state present" || echo "no project state"

Three states:

  • Legacy install (skills/ + canvas/ both present): proceed to Step 2.
  • Already migrated (canvas/ present, skills/ absent): tell the user "This project is already on plugin form. No migration needed." and exit.
  • Empty (neither present): tell the user "No Mycelium install detected. Run /mycelium:start to bootstrap a fresh plugin install." and exit.

Step 2: Verify the plugin is installed

Ask the user to confirm the plugin is installed before deleting legacy framework files. If they don't have the plugin yet, deleting framework files would leave them with no Mycelium at all.

Tell them to run inside Claude Code:

/plugin marketplace add haabe/mycelium
/plugin install mycelium@haabe-mycelium

Then ask: "Is the plugin installed now?" Wait for confirmation before continuing. Acceptable answers: "yes", "installed", "done", or running /mycelium:ping to verify the plugin loaded (returns a deterministic marker if so).

If the user says no or seems uncertain, exit and tell them to come back after installing.

Step 3: Verify a clean working tree

The migration is reversible via git, so the project must be a git repo with a clean working tree before proceeding. Run:

cd "$CLAUDE_PROJECT_DIR"
git rev-parse --is-inside-work-tree  # must succeed
git diff-index --quiet HEAD --        # must succeed (no uncommitted changes)

Read the full file on GitHub · 201 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. 9d ago First seen · 201 lines · 86 tokens per session scan A 45025a35cb9f

Subscribe to this mod's changes

migrate-from-legacy is a skill published in the GitHub repository haabe/mycelium (45 stars, last pushed 2d ago), licensed MIT. It adds 86 tokens to every session and 2,817 once invoked, about $0.0004 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

skill-finder

Find the right Affitor skill for your goal. Triggers on: "which skill should I use", "find me a skill", "what skills are available", "help me choose a skill", "skill for SEO", "skill for email", "explore skills", "I'm new to Affitor", "what can Affitor do", "search skills", "skill for blog writing", "skill for landing…

Affitor/affiliate-skills · 94 tokens

meraki-network-ops

Cisco Meraki organization and network operations (read-only) — org discovery, network inventory, device inventory, clients, group policies, admins, licensing, alert settings via Cisco's official Meraki MCP. Use as the entry point for any Meraki question, to discover org and network IDs, or to inventory Meraki networks…

automateyournetwork/netclaw · 72 tokens

auto

Intent-classified router, the front door to OrchestKit and the DEFAULT entry point for any goal-shaped request. Classifies a plain-English goal and routes it to the right specialist skill. Routing is never overhead, so use it even when the target skill seems obvious; skip only when already executing inside another…

yonatangross/orchestkit · 99 tokens

gingiris-user-interview

A playbook for interviewing users and operating an early product launch, including screening participants, running interviews, testing beta versions, and reviewing churn. It is based on a described process for finding product-market fit, meaning a product consistently meeting a real user need.

Gingiris-1031/gingiris-skills · 369 tokens

tao-setup

One-time session setup and orchestration map for the TAO skill bank. Run this first when the TAO skills were installed individually (e.g. from a public skills catalog) so the session gets the cross-skill discovery flow, credential checks, and host preflight that the bundled plugin hook would otherwise inject…

NVIDIA-TAO/tao-skill-bank · 97 tokens

tao-list-capabilities

Answer what the TAO Skill Bank plugin can do by generating the response from packaged application, data, model, AutoML, and platform manifests. Use when the user asks "what can TAO Skill Bank do", "list TAO models", "which TAO workflows are available", or "what supports AutoML".

NVIDIA-TAO/tao-skill-bank · 70 tokens