Using a plugin's skills in the Claude Code web environment¶

Claude Code plugins are a local CLI / IDE feature, but you can get a plugin's skills, agents, and slash commands working inside a Claude Code web session (claude.ai/code). The reliable way is to install the plugin from the environment's Setup script, which runs before Claude boots — so the plugin is on disk before Claude starts and gets picked up in the same session. This guide explains why that works, and gives a file-based fallback for restrictive environments. It uses this repo's dev-team plugin as the worked example.

TL;DR: install the plugin in the Setup script (cloud UI) → it loads this session. The claude CLI is available in cloud environments. If a network policy blocks the install, fall back to running each skill from its file: /<skill> ≡ "read plugins/<plugin>/skills/<skill>/SKILL.md and follow it."

See docs/cloud-setup.md for the focused, copy-paste setup recipe and the verification probe.

1. Why a plugin must be installed before Claude boots¶

Claude loads all skills, agents, and slash commands once, when it starts. Anything that lands on disk after that is invisible to the running session. That single fact drives everything below:

The environment Setup script (configured in the cloud UI) runs before Claude launches, and its filesystem is snapshotted and reused by later sessions. A plugin installed there is on disk before Claude starts, so it loads in the same session. This is the supported way to install software before the session starts (you cannot replace the underlying machine image).
A SessionStart hook runs after Claude has already launched. A plugin it installs is on disk too late for this session's enumeration, so it only takes effect on the next session — the "next-session effect." Useful as a fallback, but it is not the way to load the plugin into the current session.
The claude CLI is available in cloud environments, so claude plugin marketplace add … and claude plugin install … run fine from the Setup script.

So the recommended path is Option A (install via the Setup script). Option B (run skills from their files) is the always-works fallback when a network policy blocks the install.

2. Option A (recommended) — install via the Setup script¶

Paste this script into your environment's Setup script field (claude.ai/code → Environment → Setup script). It installs the repo's toolchain and the dev-team plugin before Claude boots, so the plugin's ~86 skills (including /ship) are available in the session that starts.

The body of .claude/cloud-setup.sh is exactly that script — it installs jq, shellcheck, bats, the Python dev deps (requirements-dev.txt), gh, and then the plugin (claude plugin marketplace add bdfinst/agentic-dev-team + claude plugin install dev-team@bfinster). Every step is best-effort and the script ends with exit 0 so it can never fail session startup.

For the minimal, self-contained snippet and the why/how, see docs/cloud-setup.md. Verify it worked with the headless probe:

claude -p "List the names of every skill available to you, one per line." \
  --max-turns 1 | grep -c '^dev-team:'

A non-zero count (≈86) means the plugin loaded this session.

3. Option B (fallback) — run the skill from its files (no install)¶

If a restrictive network policy blocks marketplace add / install, you don't need the plugin loaded at all: every skill, agent, and knowledge file is plain text in the repo. To "run" a slash command, read its source and follow the procedure:

You'd normally type	Do this instead
`/plan`	Read `plugins/dev-team/skills/plan/SKILL.md` and follow its steps.
`/code-review`	Read `plugins/dev-team/skills/code-review/SKILL.md`.
`/build`	Read `plugins/dev-team/skills/build/SKILL.md`.
a review agent	Read `plugins/dev-team/agents/<name>.md`.
the catalog of what's available	Read `plugins/dev-team/knowledge/agent-registry.md` (or the `## Skills Registry` table in `plugins/dev-team/CLAUDE.md`).

Concretely, just ask the agent in your web session:

"Read plugins/dev-team/skills/plan/SKILL.md and run that workflow on <task>."

Notes: - User-invocable skills (the slash commands) have user-invocable: true in their SKILL.md frontmatter — those are the ones meant to be driven this way. Other SKILL.md files are agent-loaded references the procedure will pull in as needed. - A skill may reference helper scripts as ${CLAUDE_PLUGIN_ROOT}/scripts/…. When you run it from files, that variable isn't set — substitute the in-repo path (plugins/dev-team/scripts/…) instead. - Helper scripts need their toolchain (jq, bats, python3, …); the Setup script installs these regardless of which option you use.

This path is robust precisely because it has no dependency on plugin loading — it's "read the recipe and cook."

4. The `SessionStart` hook — a documented fallback, not the primary path¶

This repo also ships a cloud-only install hook (.claude/install-dev-team.sh, registered in .claude/settings.json). It is a no-op unless DEV_TEAM_CLOUD_INSTALL=1 is set, installs the plugin when the claude CLI is present, and falls back to Option-A guidance otherwise.

It cannot load the plugin into the current session. Because the hook runs after boot, its install only takes effect on the next session (see §1). It is retained for environments where editing the Setup script isn't possible — but for same-session availability, use the Setup script (Option A).

Adapting this for your own plugin: copy .claude/install-dev-team.sh and .claude/settings.json, rename the env-var gate and the marketplace add/install targets, and keep the no-CLI fallback message.

5. Caveats specific to the web environment¶

Boot enumeration. Skills/agents/commands are enumerated once at boot. Install the plugin before boot (Setup script) to use it this session; a post-boot install (SessionStart hook) only lands next session.
Setup-script budget & exit code. The Setup script has a few-minute budget and must exit 0 — a non-zero exit fails session startup. Guard every optional step with || true and end with exit 0.
Snapshot rebuild. The Setup-script filesystem is snapshotted and reused; editing the Setup script (or other environment config) triggers a rebuild on the next session.
Ephemeral VM. Commit and push anything you want to keep before the session ends; the container is reclaimed afterward.
Network policy. Outbound access is governed by the environment's network policy chosen in the cloud UI; an install or pip step can fail under a restrictive policy — fall back to Option B.
No secrets store yet. Treat environment variables as visible to anyone who can edit the environment; don't put secrets there.

6. Quick reference¶

Install the plugin (this session): paste .claude/cloud-setup.sh into the Setup script field; see docs/cloud-setup.md.
Verify: claude -p "List the names of every skill available to you, one per line." --max-turns 1 | grep -c '^dev-team:' → ≈86.
Slash command → file (fallback): /<name> ⇒ plugins/<plugin>/skills/<name>/SKILL.md.
Find what's available: plugins/<plugin>/CLAUDE.md (registry tables) or plugins/<plugin>/knowledge/agent-registry.md.
Next-session fallback only: set DEV_TEAM_CLOUD_INSTALL=1 to enable the SessionStart hook.
Authoritative summary: CLAUDE.md → Cloud sessions (claude.ai/code).