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migrations

Add or change a database column without breaking existing rows

Quality

76%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./.github/pr-assets/self-learning/demo/harness-v1/skills/migrations/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

86%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 body is an exemplar of token-efficient, actionable instruction for a database-migration safety procedure, with a clear sequence and an explicit verification step. The only meaningful gap is the absence of failure-handling guidance (what to do when validation fails) and concrete SQL examples.

DimensionReasoningScore

Conciseness

The body is four lean numbered lines with zero padding and no explanation of concepts Claude already knows (what a migration or NOT NULL constraint is). Every token earns its place, matching the 'lean and efficient; assumes Claude's competence' anchor.

5 / 5

Actionability

The guidance is concrete and specific for an instruction-only skill — nullable first, backfill in batches, then NOT NULL plus default, then idempotency check — but there are minor gaps: no SQL/command examples and no indication of batch size or backfill technique. This matches 'mostly executable guidance with minor gaps' rather than the fully copy-paste-ready score-5 anchor.

4 / 5

Workflow Clarity

The four steps are clearly sequenced and include an explicit validation checkpoint ("Run the migration twice against a copy of the database; it must be idempotent"), so the batch/database cap at 3 does not apply. However, there is no feedback loop stating what to do if the dry run or idempotency check fails, which keeps it below the score-5 anchor.

4 / 5

Progressive Disclosure

The skill is under 50 lines, single-purpose, and needs no external references; the numbered list is well-organized with no inlined content that belongs in separate files. Per the simple-skill guideline, this earns a 5.

5 / 5

Total

18

/

20

Passed

Description

53%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 states a clear, concrete capability in third person with a distinct niche, but it omits any 'Use when...' trigger guidance and misses the natural vocabulary users would employ (migration, schema change, ALTER TABLE). It is serviceable but below the quality of the reference good examples.

Suggestions

Add an explicit trigger clause, e.g. "Use when adding or altering database columns, running schema migrations, or changing table structure on tables with existing data."

Include natural synonyms users actually say — "migration", "schema change", "ALTER TABLE", "backfill" — to improve trigger-term coverage.

Optionally mention the safety guarantee's payoff (zero-downtime, no data loss) in concrete terms to sharpen the 'what' beyond a single action.

DimensionReasoningScore

Specificity

"Add or change a database column" names the domain and one concrete action, but offers no broader coverage of related capabilities, matching the anchor for 1-2 concrete actions without comprehensiveness. It is far more concrete than the generic score-2 example ('Processes PDF files') but does not list the several specific actions required for a 4.

3 / 5

Completeness

The 'what' is clear ("Add or change a database column without breaking existing rows") but there is no 'when' clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines. It clearly exceeds score 2 (vague what) but lacks the explicit 'when' required for 4.

3 / 5

Trigger Term Quality

"database column" and "rows" are relevant keywords a user might say, but common natural variations are missing — users would typically say "migration", "schema change", "ALTER TABLE", or "add a column". This matches the anchor for some relevant keywords missing common variations or synonyms.

3 / 5

Distinctiveness Conflict Risk

The niche is clear and specific — safe column additions/changes on existing tables — with only minor overlap risk against general database or ORM skills, comparable to the anchor-4 example 'Works with PDF and Word document files'. It lacks the explicit distinct trigger phrases of a score-5 description.

4 / 5

Total

13

/

20

Passed

Validation

100%

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

shep-ai/shep

Path

.github/pr-assets/self-learning/demo/harness-v1/skills/migrations/SKILL.md

Reviewed

Table of Contents

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