clickhouse-migrations

ClickHouse migration patterns and rules. Use when creating or modifying ClickHouse migrations.

Quality

74%

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tessl review fix ./.agents/skills/clickhouse-migrations/SKILL.md

Quality

Content

75%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.

A high-quality, operationally specific reference that assumes expertise, gives executable commands with validation gates, and cleanly defers deep detail to AGENTS.md. The main gaps are minor: a few placeholder code templates and some dense inline tables that could be pushed deeper.

Suggestions

Replace the `SQL_FUNCTION()` / `node_roles=[...]` placeholders in the migration-structure example with a minimal real snippet so the canonical example is copy-pasteable.

Move the full run_mode predicate table and engine reference into AGENTS.md, keeping only the most common predicate (`is_deployed_cloud`) inline, to tighten the quick reference and deepen progressive disclosure.

Add a short numbered 'write a migration' checklist (pick node role → write operations → gate with run_mode → update schema.py tuple → update HCL → check.sh) so the end-to-end workflow is explicit rather than dispersed across sections.

Dimension	Reasoning	Score
Conciseness	The body is dense and assumes Claude's competence — no padding explaining what ClickHouse is — and most rationale (CODEC, Kafka settings) is PostHong-specific knowledge Claude lacks; a few prose passages could be trimmed.	4 / 5
Actionability	Provides concrete, copy-pasteable commands (`bash $HCL/gen-golden.sh`, `bash $HCL/check.sh`) and real code (run_mode gating, Kafka SETTINGS baseline); the migration-structure example uses placeholders like `SQL_FUNCTION()` and `node_roles=[...]`, leaving minor gaps.	4 / 5
Workflow Clarity	Destructive/batch operations carry explicit validation checkpoints (HCL `check.sh must exit 0`, CI `DRIFT:` failure, the two-step DROP COLUMN process), and the HCL section is a clear sequenced workflow; the skill is reference-organized rather than one end-to-end flow, so it stops short of full workflow maturity.	4 / 5
Progressive Disclosure	Clearly defers comprehensive detail one level deep to `posthog/clickhouse/migrations/AGENTS.md` and `hcl/README.md` with well-signaled 'Read X for...' framing, and sections are well-organized; some dense inline reference (engine tables, run_mode predicates) could arguably live behind those references.	4 / 5
	Total	16 / 20 Passed

Description

73%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.

A concise, third-person description that clearly states the niche and provides an explicit 'Use when' trigger. It is distinct and well-targeted, though the 'what' could enumerate more concrete migration capabilities and add a few natural synonyms.

Suggestions

Expand the 'what' with concrete capabilities (e.g. '...creating, modifying, and altering ClickHouse tables, Kafka engines, and materialized views') to lift specificity and completeness.

Add a synonym or alternate phrasing in the trigger (e.g. '...or when the user mentions ClickHouse schema changes / DDL') to broaden natural keyword coverage.

Dimension	Reasoning	Score
Specificity	Names the domain ('ClickHouse migration patterns and rules') and two concrete actions ('creating or modifying'), but coverage is not comprehensive — no mention of specific migration tasks like altering engines, adding columns, or Kafka tables.	3 / 5
Completeness	Both 'what' ('ClickHouse migration patterns and rules') and 'when' ('Use when creating or modifying ClickHouse migrations') are present and the trigger is explicit; the 'what' is somewhat abstract ('patterns and rules') rather than listing concrete capabilities.	4 / 5
Trigger Term Quality	'ClickHouse', 'migrations', and 'creating or modifying' are natural terms a user would say when needing this skill; good coverage, though a few natural synonyms (e.g. 'schema change', 'DDL') are absent.	4 / 5
Distinctiveness Conflict Risk	Targets a clearly delineated niche (ClickHouse migrations) with distinct triggers, so it is unlikely to fire for unrelated skills.	5 / 5
	Total	16 / 20 Passed

Validation

100%

Warnings & errors only

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: PostHog/posthog
Path: .agents/skills/clickhouse-migrations/SKILL.md
Commit: 130f3a1

Reviewed: 9 days ago

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