Agent Plugins

Turn a useful workflow into a reusable agent capability—and test whether it actually helps.

Writing instructions is easy. Making them discoverable, portable, safe to distribute, and measurably useful is harder. Agent Plugins guides you from an idea to a validated Skill, custom agent, lifecycle hook, or complete plugin, with evidence to support improvements.

The portable core follows Agent Skills and Agent Plugins specifications: runtime-agnostic by format, with host-specific behavior clearly separated. Goose, an open-source Agentic AI Foundation project, is the verified reference host. Compatibility with other hosts depends on their implementation and is not claimed without testing.

Quick start · Choose a creator · Examples · Contribute

What you can do

• Create reusable capabilities: turn a concrete need into focused instructions and only the supporting files it needs.
• Avoid packaging mistakes: validate metadata, references, manifests, safe paths, and runtime boundaries before sharing.
• Measure usefulness: use paired A/B runs on the same scenarios to compare a Skill with its previous version or with no Skill.
• Improve from evidence: inspect outputs, grading, timing, and regressions in a browser report instead of assuming a longer prompt is better.

Four creators cover authoring and validation; a fifth Skill helps package executable scripts.

Status	Value
Distribution	0.5.0
Portable plugin target	Agent Plugins 1.0.0
Verified host integration	Goose 1.47.0
Git installation requirement	Node.js 22+; creator code and dependencies included
License	CeCILL-C

See it in action

Describe the outcome you want, not the file format you think you need:

Use agent-plugins:skill-creator to create .agents/skills/api-review. It should review an OpenAPI diff for breaking changes and produce a concise Markdown report. Keep it portable, add realistic evaluation cases, validate the result, and show me the files and any missing evidence.

What you get: a focused SKILL.md, supporting resources where needed, and a validation result. Behavioral evaluation is reported separately: unavailable evidence is a blocker, not a pass.

Already have a Skill? Compare with_skill with old_skill or without_skill using the same cases. Evaluation can produce benchmark.json, benchmark.md, and a static HTML report such as review.html, so you can review outputs and grading side by side. Measured gains, regressions, and inconclusive results stay distinct.

Quick start

1. Have a host and Node.js ready

Use Goose for the integration verified by this project, or a host that supports the relevant open format. For a Git installation, confirm Node.js 22 or newer is available:

node --version

You do not need to build the project, install npm dependencies, or install Bun to use the Git distribution. Each executable creator includes compiled code and production dependencies inside its own Skill directory.

2. Install the plugin

In a terminal:

goose plugin install https://github.com/bioinfornatics/agent-plugins.git

This installs the upstream production distribution from the generated main branch. Only install plugins you trust: instructions and executable resources can affect your local environment.

3. Confirm discovery

Start a new Goose session and ask:

Use agent-plugins:skill-creator to explain what information you need to create a Skill. Do not modify any files yet.

Success: Goose resolves the creator and explains the desired behavior, activation conditions, workflow, and evaluation needs.

4. Create your first Skill

From the project where you want to use it, ask:

Use agent-plugins:skill-creator to create .agents/skills/markdown-summary. It should summarize one Markdown file into key decisions and open questions. Keep it simple and portable, validate it, and show me what was created and what still needs evaluation.

Success: .agents/skills/markdown-summary/SKILL.md exists, format validation is reported, and evaluation is either supported by evidence or explicitly blocked. Review the generated files before using them.

Choose the right creator

You want to…	Ask for	Output
Create, improve, or A/B evaluate one Skill	agent-plugins:skill-creator	Portable Agent Skill
Create or improve a custom agent	agent-plugins:agent-creator	Goose custom-agent definition
Create or validate a lifecycle hook	agent-plugins:hook-creator	Explicit Goose hook adapter
Create, validate, migrate, or package a complete plugin	agent-plugins:plugin-creator	Portable core with explicit host adapters
Package scripts for Git and native installations	agent-plugins:plugin-script-packaging	Contained runtime and executable packaging guidance

For standalone installations, use the plain name, such as skill-creator. A useful request specifies the outcome, destination, constraints, and success criteria.

Choose your path

• New user: follow the quick start, then try one focused workflow.
• Existing Skill author: compare versions with the evaluation example.
• Plugin maintainer: use agent-plugins:plugin-creator for package-level validation and release readiness.
• Contributor: read CONTRIBUTING.md for source setup, builds, tests, and the branch lifecycle.

How-to guides

Create a complete plugin

Use agent-plugins:plugin-creator to create ./release-assistant with a portable Skill for drafting release notes. Validate it in portable-load and strict-authoring modes, separate any host-specific behavior, and show me the package before making an archive.

Look for: a valid plugin.json, independently contained components, and actionable validation diagnostics.

Evaluate and improve a Skill

Use agent-plugins:skill-creator to evaluate .agents/skills/api-review against its previous version on the same realistic scenarios. Preserve paired outputs, grade both variants using explicit evidence, generate the HTML review, identify regressions and trade-offs, and recommend only evidence-backed changes.

Look for: traceable comparisons, not a blanket claim of improvement. Format validation answers “does it conform?”; evaluation answers “does it help?” Missing execution, grading, timing, or human review must remain explicit.

Add a lifecycle hook

Use agent-plugins:hook-creator to add a safe lifecycle hook to ./my-plugin. Use a plugin-relative script, explain its side effects, and validate the hook before enabling it.

Look for: an existing valid plugin manifest, contained script paths, and reviewed executable behavior. Hooks are host-specific, not part of the portable core.

Installation and updates

Enable automatic updates

Choose this instead of the manual-update installation above if you want Goose to check for updates automatically:

goose plugin install --auto-update https://github.com/bioinfornatics/agent-plugins.git

For a Git-backed installation, update on demand with:

goose plugin update agent-plugins

Install just one Skill

If your host supports standalone Skills, copy the whole Skill directory, not only SKILL.md. For example, on Linux or macOS:

git clone https://github.com/bioinfornatics/agent-plugins.git
cd agent-plugins
mkdir -p ~/.agents/skills
cp -R skills/skill-creator ~/.agents/skills/skill-creator

Goose discovers global Skills in ~/.agents/skills/ and project Skills in .agents/skills/. Check other hosts’ documented discovery rules; there is no universal installation command.

Prefer native executables?

Tagged releases provide platform-specific archives that do not require Node.js. Select the matching OS/architecture and verify SHA256SUMS before extraction. See the release installation guide for filenames and commands. Goose’s Git installer does not automatically select native archives; manually copied installations are updated separately.

Troubleshooting

Problem	Next step
Creator not found	Start a new session. Use agent-plugins:skill-creator for a plugin install or skill-creator for a standalone install.
Git-installed creator will not launch	Check node --version and that the entire Skill directory, including runtime/, is present.
Installed runtime reports missing dependencies	Reinstall a complete distribution and report the defect; do not repair an installation with npm install.
Validation fails	Follow the diagnostic for the named file or field; do not bypass the authoring gate.
Evaluation is blocked	Supply the requested execution or review evidence, then resume. Blocked does not mean passed.
Native command is the wrong version	Check your PATH and archive architecture; do not mix native archives with old Node wrappers.

Report reproducible defects in the upstream issue tracker. The ServierHub fork does not maintain a separate issue queue.

Formats, portability, and security

• Skills carry reusable instructions and resources; plugins package capabilities for distribution.
• The supported portable target is Agent Plugins 1.0.0. Custom agents and hooks currently use explicitly identified Goose contracts.
• Review generated commands, file writes, credentials, and side effects before enabling executable behavior. Never package secrets.
• Validation is not a substitute for behavioral testing or human review. Missing evidence never becomes a positive result.

For details, see portable conformance and the Goose adapter reference.

Learn more and contribute

• Component guides: Skill Creator, Agent Creator, Hook Creator, Plugin Creator, Script Packaging.
• Development: CONTRIBUTING.md explains how source becomes a ready-to-install distribution. Feature PRs target develop; main is generated production, not a source merge.
• Distribution: ServierHub fork. Upstream source and issues: bioinfornatics/agent-plugins. Publication status is repository-specific; the fork may carry its own presentation or release commits.
• Host documentation: Goose Plugins and Agent Skills.
• License: CeCILL-C. Manifest: plugin.json.