clickhouse-migrations

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

Quality

81%

Does it follow best practices?

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Securityby

High

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Quality

Content

87%

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

The content is highly actionable and token-efficient, with concrete code patterns, real API identifiers, and well-organized sections pointing to one external reference. Its only meaningful gap is the absence of explicit validation/verification checkpoints for destructive migration operations, which caps workflow clarity.

Suggestions

Add an explicit validation checkpoint for destructive operations, e.g. 'run the migration locally and confirm it applies cleanly before opening the PR' or a validate->fix->retry loop, to lift workflow_clarity from 2 to 3.

Expand the one-line Testing section into a short sequence (clear the infi_clickhouse_orm_migrations row -> re-run -> verify table state) so verification is part of the stated workflow.

Dimension	Reasoning	Score
Conciseness	The body is lean and assumes Claude's competence — terse rules ("NEVER use `ON CLUSTER`", "Always use `IF EXISTS`") and compact tables/snippets with no padding explaining what ClickHouse or merge trees are, matching 'lean and efficient; every token earns its place.'	3 / 3
Actionability	Provides copy-paste-ready patterns with real named APIs and real arguments (run_sql_with_exceptions with node_roles/sharded/is_alter_on_replicated_table flags, engine constructors, get_clickhouse_creds interpolation, the schema.py tuple table), matching 'fully executable code/commands; copy-paste ready.'	3 / 3
Workflow Clarity	Sequences are present (DROP COLUMN two-step, migration-before-app-code ordering, local-parity flow), but for destructive/batch operations (DROP TABLE SYNC, DROP COLUMN, replicated table recreation) there is no explicit validate-then-fix feedback loop, which per the rubric caps workflow clarity at 2.	2 / 3
Progressive Disclosure	A single one-level-deep reference is clearly signaled up top ("Read `posthog/clickhouse/migrations/AGENTS.md`...") and the in-skill content is well-organized into clearly headed sections, matching 'clear overview with well-signaled one-level-deep references' despite there being no separate bundle files.	3 / 3
	Total	11 / 12 Passed

Description

75%

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 concise and clearly scoped to ClickHouse migrations with an explicit 'Use when' trigger, giving it strong completeness and distinctiveness. It is slightly weak on specificity and trigger-term breadth, naming only 'creating or modifying' and a single keyword family rather than a fuller action list or term coverage.

Suggestions

Expand the action list to name more concrete migration tasks (e.g. adding columns, creating tables, altering replicated tables, defining materialized views) to lift specificity from 2 to 3.

Broaden trigger terms to include common variations a user might say, such as 'schema changes', 'ClickHouse DDL', or 'database migrations'.

Dimension	Reasoning	Score
Specificity	Names the domain ("ClickHouse migration patterns and rules") and concrete actions ("creating or modifying ClickHouse migrations") but does not list multiple distinct concrete actions, so it lands at 'names domain and some actions, not comprehensive' rather than the multiple-action anchor.	2 / 3
Completeness	Both halves are explicit: the "what" ("ClickHouse migration patterns and rules") and the "when" ("Use when creating or modifying ClickHouse migrations"), satisfying the anchor for clearly answering both with explicit triggers.	3 / 3
Trigger Term Quality	"ClickHouse migration(s)" is a natural term users would say, but coverage is a single keyword family with missing common variations (e.g. schema change, DDL, ClickHouse SQL), matching 'some relevant keywords but missing common variations.'	2 / 3
Distinctiveness Conflict Risk	"ClickHouse migration" is a clear, narrow niche with distinct triggers that is unlikely to fire for unrelated skills, matching the 'clear niche with distinct triggers' anchor.	3 / 3
	Total	10 / 12 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: d1dd198

Reviewed: about 14 hours ago

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