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Agent Zero Plugin Management

skills/a0-manage-plugin/SKILL.md

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Agent Zero Plugin Management

Action Routing

Identify what the user needs and jump to the relevant section:

User needSection
Find / search / browse available pluginsBrowse Plugin Hub
Scan a plugin for security issuesSecurity Scan
Install a pluginInstall a Plugin
Update an installed pluginUpdate a Plugin
Uninstall / remove a pluginUninstall a Plugin
Enable or disable a pluginActivation
Plugin not loading / crashing / missingRead /a0/skills/a0-debug-plugin/SKILL.md
Explain how plugin discovery worksRead /a0/skills/a0-debug-plugin/SKILL.md

Browse Plugin Hub

Fetch the current community index:

python
import urllib.request, json

url = "https://github.com/agent0ai/a0-plugins/releases/download/generated-index/index.json"
with urllib.request.urlopen(url, timeout=30) as resp:
    index = json.loads(resp.read())

plugins = index.get("plugins", {})

Each entry in plugins is keyed by plugin name with fields: title, description, github, tags, thumbnail (URL if available).

To search: filter by keyword in title, description, or tags.

To list installed plugins locally:

bash
ls /a0/usr/plugins/

Alternatively via UI: Open the Plugins dialog in Agent Zero and switch to the Browse tab (or click Install in the toolbar to open the Plugin Hub).


Security Scan

The _plugin_scan plugin provides an LLM-driven security scanner that clones the repository, reads all files, and produces a structured markdown report covering 6 checks: structure match, static code review, agent manipulation detection, remote communication, secrets access, and obfuscation.

Pre-install scan protocol (follow this for every install)

Always offer to scan before installing. If the user hasn't explicitly declined, say:

"Before installing, I strongly recommend running a security scan on this plugin. Third-party plugins execute code inside your Agent Zero environment. Should I scan it first? The scan typically takes 2-4 minutes."

If the user declines, acknowledge but warn once:

"Understood, skipping the scan. Note that installing unscanned third-party code carries security risks. Proceeding with installation."

Then proceed to install. Do not ask again after the user declines.

Running a scan

python
# (after authentication setup - see Install section)
resp = s.post(
    f"{BASE}/api/plugins/_plugin_scan/plugin_scan_run",
    json={
        "git_url": "https://github.com/<user>/<plugin-repo>",
        "checks": ["structure", "codeReview", "agentManipulation", "remoteComms", "secrets", "obfuscation"],
    },
    headers={"X-CSRF-Token": token, "Origin": ORIGIN},
    timeout=600,   # set generously - the scan clones the repo, reads all files, runs 6 LLM checks
)
data = resp.json()

Always pass the full checks list explicitly - omitting it has been observed to cause intermittent failures. To run a subset, remove unwanted keys from the list.

Interpreting the result

python
report = data["report"]   # full markdown security report

Present the full report to the user. Read the Summary section to determine the overall verdict (Safe / Caution / Dangerous) and act accordingly:

VerdictAction
SafeOffer to proceed with installation
CautionShow findings, warn that issues were found, ask for explicit confirmation: "Some warnings were found. Do you still want to install?"
DangerousShow findings, strongly advise against installing: "The scanner flagged serious security issues. I strongly recommend NOT installing this plugin. Do you want to proceed anyway?" Only install if user explicitly confirms.

If the scan times out or errors (500), inform the user and ask whether to proceed without a scan.


Install a Plugin

Always use the HTTP API or UI. Never import Agent Zero framework modules directly from code_execution_tool - the agent runs in a separate Python runtime (/opt/venv) that does not have the framework's dependencies. All programmatic installs must go through HTTP.

How installed state works

The Plugin Hub marks a plugin as Installed by cross-referencing Plugin Hub keys against usr/plugins/ directory names at request time. To appear installed:

  • The plugin directory must exist at usr/plugins/<name>/ with a valid plugin.yaml
  • If the plugin ships extensions, the framework will register both named extension points under extensions/python/<point>/ and implicit @extensible hooks under extensions/python/_functions/<module>/<qualname>/<start|end>/ after the plugin cache is refreshed
  • The framework plugin cache must be cleared (the API handles this automatically)
  • Re-fetching the Plugin Hub index will then show it as installed

API authentication (required for all HTTP calls)

The Agent Zero API uses CSRF protection. The Origin header is always required - without it the CSRF endpoint returns ok: false even when login is disabled.

Step 1: Set the base URL. Agent Zero listens on port 80 inside Docker (the standard deployment):

python
import requests

BASE = "http://localhost"   # port 80 inside Docker
# If running outside Docker (dev mode), check: os.environ.get("WEB_UI_PORT", "5000")

Step 2: Bootstrap the session and get the CSRF token:

python
s = requests.Session()
ORIGIN = BASE  # Origin must match a localhost pattern

r = s.get(f"{BASE}/api/csrf_token", headers={"Origin": ORIGIN}, timeout=10)
data = r.json()

if not data.get("ok"):
    raise RuntimeError(f"CSRF bootstrap failed: {data.get('error')}")

token = data["token"]
runtime_id = data["runtime_id"]

# Set the CSRF cookie (required alongside the header)
s.cookies.set(f"csrf_token_{runtime_id}", token)

Reuse s, BASE, ORIGIN, and token for all subsequent API calls. Always include headers={"X-CSRF-Token": token, "Origin": ORIGIN} on every request.

Method 1: From a Git URL (via HTTP API) - preferred for programmatic use

python
# (after authentication setup above)
resp = s.post(
    f"{BASE}/api/plugins/_plugin_installer/plugin_install",
    json={
        "action": "install_git",
        "git_url": "https://github.com/<user>/<plugin-repo>",
        # "git_token": "<token>",    # optional, for private repos
        # "plugin_name": "override"  # optional, override directory name
    },
    headers={"X-CSRF-Token": token, "Origin": ORIGIN},
    timeout=120,
)
print(resp.json())

This runs the full pipeline in the framework runtime: clone → validate → place in usr/plugins/ → run install hook → clear plugin cache → notify frontend. The Plugin Hub will show the plugin as installed on the next index fetch.

Method 2: From the Plugin Hub (UI) - preferred for interactive use

  1. Open the Plugins dialog
  2. Go to the Browse tab (or click Install)
  3. Find the plugin, click it, click Install

The UI handles everything including marking the plugin as installed in the Plugin Hub view.

Method 3: From a ZIP file (via HTTP API)

python
# (after authentication setup above)
with open("plugin.zip", "rb") as f:
    resp = s.post(
        f"{BASE}/api/plugins/_plugin_installer/plugin_install",
        data={"action": "install_zip"},
        files={"plugin_file": f},
        headers={"X-CSRF-Token": token, "Origin": ORIGIN},
    )
print(resp.json())

Or via UI: Plugins dialog -> Install -> ZIP tab -> upload file.

Manual install (last resort only)

Only use this if the HTTP API is genuinely unavailable (not because of import errors - those mean you must use the HTTP API instead).

bash
git clone https://github.com/<user>/<repo> /a0/usr/plugins/<plugin_name>

After cloning, the plugin is on disk but the framework doesn't know about it. Clear the cache and notify the frontend by calling the toggle API (off then on) which triggers after_plugin_change() internally:

python
# (after authentication setup above)
for state in [False, True]:
    s.post(
        f"{BASE}/api/plugins",
        json={"action": "toggle_plugin", "plugin_name": "<plugin_name>", "enabled": state},
        headers={"X-CSRF-Token": token, "Origin": ORIGIN},
    )

Or simply restart Agent Zero - on startup it re-scans usr/plugins/ fresh.


Update a Plugin

The framework update flow now calls pre_update() from hooks.py immediately before pulling new plugin code into place, then re-runs install() after the update if that hook exists.

Checking for updates

Do not compare version strings. Contributors often forget to bump the version, so a matching version does not mean the plugin is current. Check for new commits instead:

bash
# Is the plugin a git repo?
git -C /a0/usr/plugins/<name> rev-parse --is-inside-work-tree 2>/dev/null

# Compare local HEAD with remote HEAD (no fetch required)
LOCAL=$(git -C /a0/usr/plugins/<name> rev-parse HEAD)
REMOTE=$(git -C /a0/usr/plugins/<name> ls-remote origin HEAD | awk '{print $1}')
echo "Local:  $LOCAL"
echo "Remote: $REMOTE"
[ "$LOCAL" = "$REMOTE" ] && echo "Up to date" || echo "Update available"

If they differ, new commits exist on the remote - report this to the user as "update available" regardless of whether the version field changed.

Applying the update

If installed via Git:

bash
cd /a0/usr/plugins/<name>
git pull origin main

Then refresh the framework cache via the toggle API (see API authentication for session setup):

python
# (after authentication setup)
for state in [False, True]:
    s.post(
        f"{BASE}/api/plugins",
        json={"action": "toggle_plugin", "plugin_name": "<name>", "enabled": state},
        headers={"X-CSRF-Token": token, "Origin": ORIGIN},
    )

If not a git repo: uninstall via the API (see Uninstall a Plugin), then reinstall via the Git method above.


Uninstall a Plugin

Safety rules - read before proceeding:

  • Core plugins (in plugins/, not usr/plugins/) cannot be uninstalled via the API - the framework blocks it. Disable them instead (see Activation).
  • Always ask for explicit user confirmation before uninstalling: "Are you sure you want to uninstall <name>? This will delete all plugin files and cannot be undone."
  • Uninstalling does NOT delete plugin config files stored in usr/agents/ or project scopes.

Standard uninstall (via API)

Uses the framework's uninstall_plugin which calls the plugin's uninstall hook (if defined) before deleting. Requires an authenticated session (see API authentication in the Install section):

python
# (after authentication setup from the Install section)
resp = s.post(
    f"{BASE}/api/plugins",
    json={
        "action": "delete_plugin",
        "plugin_name": "<name>",
    },
    headers={"X-CSRF-Token": token, "Origin": ORIGIN},
)
print(resp.json())

This is the preferred method. The framework will:

  1. Call uninstall() from hooks.py (if present) - runs cleanup
  2. Delete the usr/plugins/<name>/ directory
  3. Notify the frontend to refresh the plugin list

Via UI: Plugins dialog -> find the plugin -> click the delete (trash) icon -> confirm.

Fallback: direct folder removal

Use this only if the standard uninstall fails (e.g., broken uninstall hook that crashes or hangs):

bash
# Confirm the plugin is a custom one (usr/plugins/) - NEVER delete from plugins/
ls /a0/usr/plugins/<name>/

# Remove it
rm -rf /a0/usr/plugins/<name>/

After manual removal, refresh the plugin list via the UI or restart Agent Zero.


Activation

Plugins are enabled/disabled via toggle files:

  • .toggle-1 = explicitly ON
  • .toggle-0 = explicitly OFF
  • No file = default (enabled for most plugins)

Enable a plugin:

bash
rm -f /a0/usr/plugins/<name>/.toggle-0
touch /a0/usr/plugins/<name>/.toggle-1

Disable a plugin:

bash
rm -f /a0/usr/plugins/<name>/.toggle-1
touch /a0/usr/plugins/<name>/.toggle-0

Via UI: Plugins dialog -> find the plugin -> use the toggle switch.

Plugins with always_enabled: true in plugin.yaml cannot be toggled (framework core plugins only).

Scoped toggles (when per_project_config or per_agent_config is true): use the "Switch" modal in the UI, or place toggle files in the appropriate scoped path:

  • Project scope: project/.a0proj/plugins/<name>/.toggle-1
  • Agent profile scope: usr/agents/<profile>/plugins/<name>/.toggle-1

References

  • Plugin architecture: /a0/docs/agents/AGENTS.plugins.md
  • Developer lifecycle guide: /a0/docs/developer/plugins.md
  • Debug a broken plugin: read /a0/skills/a0-debug-plugin/SKILL.md
  • Create a new plugin: read /a0/skills/a0-create-plugin/SKILL.md
  • Review a plugin: read /a0/skills/a0-review-plugin/SKILL.md