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testland/event-sourcing-tests

Build event-sourcing + CQRS tests - the given-events / when-command / then-events aggregate test, replay determinism (same events produce the same state), event-versioning + upcasting, snapshot equivalence (replay-to-N vs snapshot-at-N must agree), retroactive event correction, and CQRS read-model projection tests (per-event projection deltas, idempotent + out-of-order apply, rebuild + zero-downtime swap, read-your-writes guard) with eventual-consistency convergence-window assertions in references/convergence-windows.md. Per martinfowler.com EventSourcing + CQRS references. Use when an event-sourced aggregate gains a new event type or a changed payload schema, when snapshots are introduced to shorten replay, when a read model is projected from the event stream, or when a documented convergence window needs a test.

72

Quality

90%

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Overview
Quality
Evals
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Quality

Content

78%Weight 40%Scale 1-5

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

The content is well-structured with a clear worked example, sequenced workflows, validation checkpoints, and clean progressive disclosure into three real reference files. It is slightly verbose in framing prose and defers some operational detail to references, keeping most dimensions at 4 with progressive disclosure at 5.

DimensionReasoningScore

Conciseness

The body is dense and assumes Claude's knowledge of event sourcing rather than over-explaining it, with only minor framing prose (the opening paragraph and Fowler quotes) that could be trimmed; it does not reach the fully lean anchor of 5.

4 / 5

Actionability

It includes a copy-paste-ready Python worked example and concrete parameterized cases (e.g. 'ProductPriceChanged -> {"sku1.price": 120}'), but much of the operational detail (snapshot equivalence, upcasting, swap mechanic) is deferred to references rather than given inline, leaving minor gaps.

4 / 5

Workflow Clarity

The 'How to use' and 'Projection rebuild' sections give clearly sequenced numbered steps with validation checkpoints (assert state_a == state_b, snapshot-at-N == replay-to-N, read-your-writes guard) and an anti-patterns error->fix table, but a couple of checkpoints are implicit rather than explicit validate->retry loops.

4 / 5

Progressive Disclosure

SKILL.md is an overview that links to three real one-level-deep reference files (snapshot-versioning-projections.md, rebuild-swap-and-read-your-writes.md, convergence-windows.md), all clearly signaled with markdown links and a References section, with no nested references.

5 / 5

Total

17

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20

Passed

Description

100%Weight 40%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.

The description is highly specific, lists concrete capabilities, and pairs a clear 'what' with an explicit 'Use when...' trigger clause. It uses third-person voice and is clearly distinguishable from sibling skills.

DimensionReasoningScore

Specificity

The description enumerates many concrete, specific test actions - 'given-events / when-command / then-events aggregate test, replay determinism', 'event-versioning + upcasting', 'snapshot equivalence', 'projection tests... rebuild + zero-downtime swap, read-your-writes guard' - matching the comprehensive-coverage anchor.

5 / 5

Completeness

It explicitly answers both 'what' (the full list of tests to build) and 'when' (an explicit 'Use when...' clause with concrete trigger phrases), matching the anchor that requires both with concrete triggers.

5 / 5

Trigger Term Quality

It includes a concrete 'Use when...' clause with natural domain trigger phrases ('when an event-sourced aggregate gains a new event type or a changed payload schema', 'when snapshots are introduced', 'when a read model is projected'), giving comprehensive natural-term coverage.

5 / 5

Distinctiveness Conflict Risk

It occupies a clear niche (event-sourcing + CQRS test patterns) with distinct triggers and even names a boundary skill ('saga-transaction-tests'), so conflict risk is minimal.

5 / 5

Total

20

/

20

Passed

Validation

93%

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

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

Total

15

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16

Passed

Reviewed

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