Borrowing it
Nothing to install: this file belongs to sponge-b0b/Polaris. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/sponge-b0b/Polaris/main/.agents/skills/database-migrations/SKILL.mdgit clone --depth 1 https://github.com/sponge-b0b/PolarisWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/sponge-b0b/polaris/database-migrations)<a href="https://agentmods.dev/skills/sponge-b0b/polaris/database-migrations"><img src="https://agentmods.dev/badge/skills/sponge-b0b/polaris/database-migrations.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00050 | $0.03138 |
| Opus 5 | $0.00025 | $0.01569 |
| Sonnet 5 | $0.00010 | $0.00628 |
| Haiku 4.5 | $0.00005 | $0.00314 |
Grade A, and why
database-migrations scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 344 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Migrations
Objective
Keep PostgreSQL schema, SQLAlchemy models, and Alembic history correct for the repository's current release lifecycle.
Before 1.0, schema and migration correctness outrank existing data. After 1.0, migration history and persisted data must be preserved.
A valid downgrade() proves schema reversibility. It does not imply destroyed data can be recovered.
Pre-flight
Before modifying database-affecting code:
- identify the authoritative SQLAlchemy models and persistence contracts;
- confirm schema evolution uses Alembic rather than ad hoc runtime DDL;
- read
[project].versionfrompyproject.toml; - if the Living Entity Wiki exists, invoke
$wiki-sync; - halt on blocking architecture findings such as
[source-conflict].
[project].version is authoritative for migration lifecycle. Git tags are corroborating only.
Before any pytest invocation, follow the mandatory test-service preflight in
AGENTS.md and docs/process/testing-guide.md. Determine the selected scope's
complete external prerequisites and verify them before pytest starts. Missing
prerequisites leave required verification unresolved.
For local PostgreSQL-backed work, .env is the canonical local environment
input. Run database preflights, migrations, database-backed pytest, and Python
database probes through uv run --locked --env-file .env .... Do not manually source
.env merely to populate the current shell, and never use bare python for a
database preflight; use uv run --locked --env-file .env python ... so project
dependencies and database configuration are established by the same command.
CI must provide its database environment explicitly at the job level. CI does
not depend on a developer .env file.
PostgreSQL URL Roles
POLARIS_DATABASE_URL is the canonical application/runtime and ordinary Alembic
migration target.
POLARIS_TEST_DATABASE_URL is an explicit PostgreSQL test target and live-test
opt-in. It does not imply that a second physical database must exist. Tests
must never implicitly fall back from POLARIS_TEST_DATABASE_URL to
POLARIS_DATABASE_URL when the test target is absent.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- today Changed · +16 lines · +10 tokens per session 0e95a4398b34
- 7d ago First seen · 328 lines · 40 tokens per session scan A 4426ac374034
database-migrations is a skill published in the GitHub repository sponge-b0b/Polaris (4 stars, last pushed today), licensed Apache-2.0. It adds 50 tokens to every session and 3,138 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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