Proposal: unified, reversible multi-agent installation

Proposal: unified, reversible multi-agent installation

Users currently follow separate installation and activation instructions for each agent. Could we add a standard-library Python script that exposes list, install, update, uninstall, status and portable Markdown export?

The proposed CLI accepts repeated --agent, an explicit --project directory or --user scope, and on-demand/always-on modes. Mutations require --apply; otherwise it prints a preview. The canonical skill and existing installation methods remain unchanged.

Each documented agent has a capability entry: automatic for verified filesystem routes, guided for native/UI routes that cannot safely be owned by the script, unsupported for undocumented mode/scope combinations. Guided routes give the existing procedure and source file, never claim installation succeeded. Managed files/blocks carry hashes and shared ownership; user edits block destructive updates/removal.

Coverage: Antigravity, AstronClaw, Claude Code, Codex, Gemini CLI, Copilot, Hermes, Kimi, OpenCode, Pi, OMP, Qwen, Zed, Cursor and Amp, plus generic export. Both modes are represented without silently substituting one for another.

PR #139 overlaps in the topic of activation but changes runtime delivery, hooks and plugin options. This proposal adds no hooks or new response rules. Existing npx skills and native installers remain valid, with guided use when necessary.

Tests will use temporary configurations and check idempotence, transitions, edits, shared files, previews and failures. Cross-platform CI will cover Windows, Linux and macOS. Actual runtime validation and untested routes will be identified separately.

Prepared with Codex (GPT-6). A local prototype is available for discussion; maintainer feedback and complete human diff review are pending. The companion PR will remain a draft while these are pending.

Proposed capability matrix

A = automatic file management for install/update/uninstall/status. G = guided, no installation mutation. U = unsupported mode/scope; portable export is available without promising equivalent activation. Columns describe this manager, not every capability of the agent itself.

Agent	Project: on-demand / always-on	User: on-demand / always-on
Antigravity	U / U	G / A
AstronClaw	G / U	G / U
Claude Code	A / A	A / A
Codex	A / A	A / A
Gemini CLI	G / G	A / A
GitHub Copilot	A / A	A / G
Hermes	G / A	A / G
Kimi Code CLI	G / U	G / U
OpenCode	A / G	A / A
Pi	U / U	G / G
Oh My Pi (OMP)	U / U	G / U
Qwen Code	U / U	G / U
Zed	G / G	A / A
Cursor	A / A	A / G
Amp	G / U	G / U
Generic	G / G	G / G

Guided native/UI routes deliberately stay under their original installer: this script cannot hash or safely undo changes inside an opaque package store. It prints the source file, relevant procedure and missing CLI dependency. It does not install that dependency, execute displayed commands, import through a UI, or record manual work as completed. The proposed v1 therefore automates filesystem routes, not native package-manager mutations.

Related history: issue #2 closed after the old install-user.sh was removed in favor of marketplace installation. This proposal is additive and keeps that native route available. No matching unified-manager implementation appeared in the open/closed installation searches.