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/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<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="Reviewed on agentmods" width="80" 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 | $0.04029 |
| Opus 5.5 | $0.00020 | $0.01612 |
| Sonnet 5.5 | $0.00010 | $0.00806 |
| Haiku 4.5 | $0.00005 | $0.00403 |
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 24d ago.
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 — 421 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 --python 3.14+gil --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 --python 3.14+gil --env-file .env python ... so project
dependencies and database configuration are established by the same command.
ADR 0005 qualifies the SQLAlchemy/greenlet-backed PostgreSQL stack only for
standard GIL-enabled CPython 3.14+. The repository default remains 3.14t, so
every PostgreSQL-owning uv run command in this skill must select
--python 3.14+gil; never rely on .python-version or the caller's active
free-threaded interpreter for these commands. The online Alembic entrypoint
must also reject GIL-disabled execution before engine construction as defense
in depth. CI must explicitly provision and select a qualified standard CPython
3.14+ runtime for PostgreSQL-owning commands.
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.
- 24d ago Changed · +68 lines 6ac69d9b2201
- 1mo ago Changed · +9 lines 34eee76d6373
- 1mo ago Changed · +16 lines · +10 tokens per session 0e95a4398b34
- 1mo 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 4,029 once invoked, about $0.0002 per session on Opus 5.5. 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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