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event-store-design

Design and implement event stores for event-sourced systems. Use when building event sourcing infrastructure, choosing event store technologies, or implementing event persistence patterns.

52

Quality

59%

Does it follow best practices?

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tessl review fix ./plugins/antigravity-bundle-ddd-evented-architecture/skills/event-store-design/SKILL.md

The canonical home for this skill is event-store-design in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

39%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This skill provides substantial code templates that are mostly executable, but suffers from being a monolithic dump of implementation patterns without clear workflow guidance. The generic instructions ('Clarify goals, constraints, and required inputs') add no value, and the core concepts section explains things Claude already knows. The content would benefit greatly from being restructured into a concise overview with technology-specific details in separate files, and adding a clear decision workflow for choosing and implementing an event store.

Suggestions

Replace the generic instructions with a concrete workflow: 1) Identify requirements (throughput, query patterns), 2) Select technology using the comparison table, 3) Implement schema using the appropriate template, 4) Validate with test events, 5) Verify concurrency handling.

Move the four implementation templates into separate bundle files (e.g., templates/postgresql.md, templates/dynamodb.md) and keep only a brief overview with navigation links in SKILL.md.

Remove the Core Concepts section (architecture diagram, requirements table) — Claude already understands event sourcing fundamentals. Replace with decision criteria that help choose between technologies.

Fix the DynamoDB template's append_events method to use conditional writes (put_item with ConditionExpression) instead of batch_writer, which doesn't support optimistic concurrency as claimed.

DimensionReasoningScore

Conciseness

The skill is significantly verbose. It explains core concepts like append-only, ordered, versioned requirements that Claude already knows. The architecture diagram, requirements table, and technology comparison table add bulk without providing actionable guidance. Four full implementation templates (PostgreSQL, Python, EventStoreDB, DynamoDB) make this very long when most use cases would need only one.

2 / 5

Actionability

The code templates are concrete and largely executable — the PostgreSQL schema is copy-paste ready, and the Python EventStore class is a complete implementation with optimistic concurrency. Minor gaps include the DynamoDB template lacking actual conditional writes despite claiming concurrency support (batch_writer doesn't support conditions), and the asyncio import is missing in the subscribe method.

4 / 5

Workflow Clarity

There is no clear workflow or sequenced process for designing and implementing an event store. The instructions section is entirely generic ('Clarify goals, constraints, and required inputs. Apply relevant best practices'). There are no validation steps, no verification that the schema works correctly, no migration workflow, and no feedback loops for error recovery when setting up event store infrastructure.

2 / 5

Progressive Disclosure

The skill references 'resources/implementation-playbook.md' but no bundle files are provided, making this a dead reference. All four implementation templates are inlined creating a monolithic document (~300+ lines of code). The technology-specific templates should be in separate files with the SKILL.md providing an overview and navigation to the appropriate template based on the chosen technology.

2 / 5

Total

10

/

20

Passed

Description

78%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

This is a solid description with a well-structured 'what' and 'when' clause that clearly communicates the skill's purpose. Its main weakness is a lack of concrete, specific actions beyond the high-level 'design and implement' — it would benefit from listing specific operations or capabilities. Trigger term coverage is good but could include more synonyms and related concepts.

Suggestions

Add more concrete actions such as 'append events to streams, read event streams, manage snapshots, build projections, handle concurrency conflicts'

Include related trigger terms and synonyms like 'CQRS', 'event stream', 'append-only log', 'EventStoreDB', 'event replay' to improve discoverability

DimensionReasoningScore

Specificity

Names the domain (event stores, event-sourced systems) and mentions a couple of actions ('design and implement', 'choosing event store technologies', 'implementing event persistence patterns'), but lacks concrete specifics like particular operations (e.g., append events, read streams, handle snapshots, manage projections).

3 / 5

Completeness

Clearly answers both 'what' (design and implement event stores for event-sourced systems) and 'when' (building event sourcing infrastructure, choosing event store technologies, implementing event persistence patterns) with an explicit 'Use when' clause containing concrete trigger phrases.

5 / 5

Trigger Term Quality

Includes relevant terms like 'event store', 'event sourcing', 'event-sourced systems', 'event persistence patterns', and 'event store technologies'. Missing some natural variations users might say such as 'CQRS', 'event stream', 'event log', 'append-only store', or specific technology names like 'EventStoreDB'.

4 / 5

Distinctiveness Conflict Risk

Fairly distinct niche targeting event sourcing specifically, which is unlikely to overlap with most other skills. Minor overlap risk with general database/persistence skills or broader CQRS/DDD skills, but the specific focus on event stores provides good differentiation.

4 / 5

Total

16

/

20

Passed

Validation

90%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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