Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/willdady/platypusnpx agentmods add skills/willdady/platypus/database-schema-changesWrote 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/willdady/platypus/database-schema-changes)<a href="https://agentmods.dev/skills/willdady/platypus/database-schema-changes"><img src="https://agentmods.dev/badge/skills/willdady/platypus/database-schema-changes/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/willdady/platypus/database-schema-changes"><img src="https://agentmods.dev/badge/skills/willdady/platypus/database-schema-changes.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00037 | $0.00804 |
| Opus 5.5 | $0.00015 | $0.00322 |
| Sonnet 5.5 | $0.00007 | $0.00161 |
| Haiku 4.5 | $0.00004 | $0.00080 |
Grade A, and why
database-schema-changes 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 4d 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 — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Schema Changes
Push is for your machine; generate is what ships. Both, every time. A push with no generate leaves a dev database that works and a production deploy that never receives the change — and nothing local tells you, because your own database is already correct.
Steps
-
Edit the schema — the backend's Drizzle schema module, where the tables are declared.
-
Push it to your dev database. Needs
pnpm devup, since the push talks to a live Postgres:pnpm drizzle-kit-push -
Generate the migration. Production applies numbered
.sqlmigrations, not your schema file, so this is the step that carries the change out of your machine:pnpm drizzle-kit-generate
Done when git status shows three new or modified artefacts beside your
schema edit: a numbered .sql migration, its snapshot, and an appended journal
entry. All of them are committed, in the same commit as the schema change.
Data changes
Generate writes DDL — it reads your schema and diffs it. A backfill, a re-shaping of existing rows, or anything else that needs to reason about data is yours to write into the generated migration by hand.
Dev never runs it: the push flow applies DDL only and skips migration files
entirely, so a hand-written backfill is invisible until production. Run the
migration file against the dev container (apps/backend/scripts/start_postgres.sh
names it and its credentials):
docker exec -i platypus-postgres psql -U postgres -d postgres \
-v ON_ERROR_STOP=1 -1 < apps/backend/drizzle/<tag>.sql
The PR body states that the migration carries a data step push skips, so
every reviewer knows to apply it to their own database.
Migration number collisions
Main gained a migration with your number since you generated (parallel
branches each generate the next free number). The fix is regeneration, not
hand-renumbering: take main's migrations, discard your generated .sql,
snapshot and journal entry, and run step 3 again. Copy any hand-written data
SQL into the new file, and update tests that name the migration tag.
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.
- 4d ago Changed c5e9782a4083
- 7d ago Changed · +32 lines 67fa979d2b7d
- 1mo ago First seen · 60 lines · 37 tokens per session scan A 8ace1c0a7d7e
database-schema-changes is a skill published in the GitHub repository willdady/platypus (120 stars, last pushed yesterday), licensed MIT. It adds 37 tokens to every session and 804 once invoked, about $0.0001 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 2026-09-01.
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