How to use the Effect Framework Answers agent skill

What is an agent skill and what does the Effect skill do?

An agent skill is a folder containing a SKILL.md file. The file gives an AI agent instructions for a specific kind of task. When the agent recognises a matching request, it follows those instructions.

The Effect skill is described as answering questions about the Effect framework. When you ask an Effect question, it tells the agent to clone the Effect source repository (effect-smol) into a references folder inside your project, use an explore sub-agent to search that code for patterns, APIs and concepts, and then base the answer on the actual source and documentation.

• It applies only to Effect questions. It does not change how the agent handles other work.
• Answers should reference specific files and patterns found in the Effect codebase.
• The skill tells the agent not to answer from memory and to verify against the source.

What you need before installing the Effect skill

The skill depends on three things. Check them before you start, because the skill will not work without them.

The repository is cloned from GitHub, so the environment needs network access to github.com.

• git, to clone the Effect repository
• Network access to github.com
• An agent environment that supports sub-agents, since the skill refers to an explore agent
• A TypeScript project that uses Effect is the intended use case

How to install the Effect skill

Download the skill ZIP from this page and unzip it. Then place the resulting folder in one of the following locations, depending on how you want to use it.

For a personal skill available across your projects, put it in your user skills folder, ~/.claude/skills/. To limit it to one project, put it in that project's .claude/skills/ folder.

If you use the Claude apps, you can instead upload the skill under Settings → Capabilities → Skills.

• Personal install: ~/.claude/skills/
• Project install: .claude/skills/ inside your project
• Claude apps: Settings → Capabilities → Skills, then upload

How to trigger the Effect skill with a natural request

You do not need a special command. Ask a normal question about Effect in the project where the skill is available. The skill is meant to apply when the question is about the Effect framework's APIs, patterns or concepts.

Name Effect in your question so the request clearly matches the skill's purpose. Specific questions about a function, pattern or concept give the explore agent more to search for.

• How do I handle errors with Effect in this codebase?
• What is the Effect pattern for providing a service dependency?
• Show me where Effect's concurrency APIs are defined and how they are used.
• Explain how Effect.gen works, and point me to the source file that defines it.

What happens during the first answer and how to read the output

On the first Effect question, the skill has the agent clone the effect-smol repository into .opencode/references/effect-smol inside your project. The skill's own instructions say this location, not the skill folder, so the cloned code stays with your project.

The explore agent then searches that code. The answer should cite specific files and patterns it found. Check those references when accuracy matters, since they tell you where the claim comes from.

• The clone goes into the project, not the skill folder.
• Answers should name the files and patterns they are based on.
• If an answer does not cite source files, ask the agent to check the cloned repository.

Safety notes: scripts and network access

According to the listing, this skill does not run scripts. It does use the network, because it clones the Effect repository from GitHub.

Because each session may fetch the repository, expect network activity whenever the agent needs source it has not already fetched. Environments that block GitHub or lack git will not be able to use the skill as designed. The skill is published under the MIT licence.

• Runs scripts: no
• Uses network: yes, to clone from github.com
• Files included: SKILL.md only
• Licence: MIT

Tips for getting better answers

The skill is most useful for questions where accuracy matters and you want a traceable answer. For quick, casual questions, a full repository clone may be more overhead than you need.

Ask focused questions and follow up on the file references. Teams onboarding new members can use the same questions to show how Effect patterns appear in real source code.

• Ask about one API or pattern at a time.
• Follow the file references to confirm the answer yourself.
• Ask for the relevant source file when you want to learn a pattern.
• Skip the skill for questions that do not involve Effect.