How to use the Event Store Design agent skill

What does the Event Store Design skill make the agent do?

Once installed, the agent answers event-sourcing architecture questions using a structured design approach. It covers how to organise streams per aggregate, which ordering, versioning and idempotency rules to apply, and how to compare options such as EventStoreDB, PostgreSQL, Kafka, DynamoDB and Marten.

The skill lists core event store requirements: append-only storage, per-stream and global ordering, optimistic concurrency control, real-time subscriptions and idempotent writes. It also gives a short set of do's and don'ts, such as using stream IDs that include the aggregate type (for example Order-{uuid}) and not updating or deleting events.

How do you install the skill?

Download the ZIP file from this page and unzip it. For a personal setup, place the unzipped folder in ~/.claude/skills/. For a single project, place it in the project's .claude/skills/ folder.

Alternatively, you can upload the skill in the Claude apps under Settings → Capabilities → Skills.

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

How do you trigger the skill with a natural request?

You do not need a special command. Describe your event sourcing problem in plain language. The skill's description covers building event sourcing infrastructure, choosing event store technologies and implementing event persistence patterns, so requests on those topics are the ones most likely to use it.

• Which event store should I use for an order system: PostgreSQL or EventStoreDB?
• How should I name streams for my Account aggregate?
• What versioning and idempotency rules should my event store follow?
• Compare Kafka and DynamoDB as event stores for my use case.

What does the skill include for concrete work?

For concrete code or schemas, the skill points to a reference file, references/details.md, which contains a template library and worked examples. The agent reads that file when it needs them. For example, it includes a PostgreSQL event store schema with an events table, a unique constraint on stream and version, indexes for stream, global position, event type and time queries, and a snapshots table.

What are the limits and safety notes?

The skill is a guidance document rather than a tool that builds or changes anything by itself. Its output is design advice that still needs engineering review and testing. It requires nothing else to be listed, does not run scripts, and does not use the network.

• It does not write or deploy your code or database.
• It does not weigh event sourcing's complexity against its benefits, so check that trade-off yourself.
• Review and test any schema or code the agent produces before using it.

Tips for getting better answers

Give the agent your context: expected event volume, existing stack, whether you need subscriptions, and your query patterns. The skill advises indexing for your query patterns, so the more you share, the more specific the advice can be.

• State your current stack (for example, an existing PostgreSQL database).
• Say whether you need real-time subscriptions.
• Ask for the template from the reference file when you want a starting schema.
• Ask about schema evolution early, since the skill recommends versioning events from day one.