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.
npx skills add alivecontext/alive --skill system-upgradegit clone --depth 1 https://github.com/alivecontext/aliveWrote 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.
[](https://agentmods.dev/skills/alivecontext/alive/system-upgrade)<a href="https://agentmods.dev/skills/alivecontext/alive/system-upgrade"><img src="https://agentmods.dev/badge/skills/alivecontext/alive/system-upgrade/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.
<a href="https://agentmods.dev/skills/alivecontext/alive/system-upgrade"><img src="https://agentmods.dev/badge/skills/alivecontext/alive/system-upgrade.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00057 | $0.06502 |
| Opus 5.5 | $0.00023 | $0.02601 |
| Sonnet 5.5 | $0.00011 | $0.01300 |
| Haiku 4.5 | $0.00006 | $0.00650 |
Grade A, and why
alive:system-upgrade scanned grade A with 1 finding 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 1mo 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.
Runs shell commandslowCapability
Expected in a hook, worth knowing in a rule or an instructions file.
3. **Invoke the orchestrator via subprocess.run.** The skill calls `python -m system_upgrade.cli <args>` (or, in-process, dispatches through the `bin/alive` `_SUBCOMMANDS` registry) with `subprocess.run(..., shell=False, How it starts
The opening of the file, as written. The whole thing — 309 lines — stays where its author put it; the contents beside it link to each section on GitHub.
System Upgrade
Upgrade an ALIVE world from any prior version to the current target. The skill is a thin operator-facing surface; the work happens in the system_upgrade/ Python package shipped with the plugin (orchestrator + 13 locked phases). Stdlib-only, no PyYAML/ruamel.
If you are reading this on the old monolithic skill (476 lines of inline upgrade logic), that file has been retired in favour of the orchestrator. This file documents what the operator and skill agent need to know to drive it.
When It Fires
- The human runs
/alive:system-upgrade(any version of the world — v1, v2, v3.0, v3.1, v3.2). - The session-new hook detects a legacy structure and surfaces the upgrade prompt.
- The human says "upgrade my world", "migrate to the new version", "update alive".
- The human asks to inspect or restore an earlier upgrade tarball (
--rollback).
Tool version vs world version
Two distinct version concepts; the orchestrator never confuses them.
- Tool version — read from
plugins/alive/.claude-plugin/plugin.jsonversion. The version of the migrator currently installed. Used for--resumeplugin-version-skew validation and the upgrade record'stool_version_at_runfield. Never feeds world-version inference; never feeds the no-op short-circuit. - World version — derived from world content fingerprints only: path/file existence, bundle schema fingerprints, hook/script content patterns. Three signals, not four. Lowest-version-wins. When zero signals fire, refuse with
--assume-empty-worldas the explicit override. - TARGET_WORLD_VERSION — hardcoded constant in
system_upgrade/__init__.py(currently"3.2.0"). The version the redesign migrates worlds TO. The no-op short-circuit compares the world version (and every per-walnut version) against this constant — never against the tool version. Bumped in lockstep with each plugin minor that introduces world-format changes.
Phases (locked 13)
The orchestrator runs the same 13 steps every invocation. Numbers below are stable contract numbers — they appear in resume markers, runstate logs, and the phase_reached envelope field.
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.
- 1mo ago First seen · 309 lines · 57 tokens per session scan A 0927f045b75c
alive:system-upgrade is a skill published in the GitHub repository alivecontext/alive (130 stars, last pushed 16d ago), licensed MIT. It adds 57 tokens to every session and 6,502 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
crit-cli
Use when an agent needs to author or reply to crit inline comments programmatically (including multi-agent workflows commenting on shared code/plans/docs/proposals), publish or unpublish a crit review with crit share, sync a crit review to or from a GitHub PR or GitLab MR, or read/interpret a crit review JSON file.…
crit
Review code changes, a plan, a live page (running dev server), or a local HTML file with Crit inline comments and structured human feedback. Use only when the user explicitly invokes /crit or directly asks to use Crit; a generic review request does not count.
crit-story
Author a crit story and continue the interactive review loop only when the user explicitly invokes crit-story or directly asks you to generate a crit story. Do not infer this skill from generic review, PR, or diff-review requests.
fresh-start
Continue in a new chat without losing anything — writes a compact handoff to paste into a fresh conversation. Use whenever the user wants to move to a new chat or conversation, hits usage limits, says replies got slow or Claude forgets earlier details, or the conversation has grown long.
token-check
Estimate how many tokens a pasted text, an attached file or the conversation so far takes, what it means for the context window and usage limits, and how to cut it. Use when the user asks how big something is in tokens, why they keep hitting limits, or whether a file is too large to send.
doc-digest
Turn a long document, PDF, transcript, spreadsheet or log into a compact working digest the conversation can continue from. Use when the user shares or pastes something long (several pages or more) and wants to discuss, analyze, compare or use it over more than one message, or asks to summarize a document so they can…