Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add rules/prisma/prisma-next/never-hand-edit-contract-fixturesgit clone --depth 1 https://github.com/prisma/prisma-nextWrote 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/rules/prisma/prisma-next/never-hand-edit-contract-fixtures)<a href="https://agentmods.dev/rules/prisma/prisma-next/never-hand-edit-contract-fixtures"><img src="https://agentmods.dev/badge/rules/prisma/prisma-next/never-hand-edit-contract-fixtures.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 | $0.00763 | $0.00763 |
| Opus 5 | $0.00381 | $0.00381 |
| Sonnet 5 | $0.00153 | $0.00153 |
| Haiku 4.5 | $0.00076 | $0.00076 |
Grade A, and why
never-hand-edit-contract-fixtures 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 6d 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.
This is a copy
100% identical to never-hand-edit-contract-fixtures — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 42 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Never hand-edit emitted contract fixtures
CRITICAL: Never hand-edit contract.json, contract.d.ts, expected.contract.json, or any other file emitted by the contract pipeline (including migration snapshot store entries at migrations/snapshots/<hex>/contract.{json,d.ts}). These files are generated; their canonical form is whatever the emitter produces, byte-for-byte.
To bring fixtures back in sync:
pnpm fixtures:emit # regenerate everything
pnpm fixtures:check # re-emit + git diff --exit-code; fails if stale
fixtures:emit knows which packages contribute fixtures: examples, apps, sql-builder, sql-orm-client, extension build:contract-space, extension migration regen (migrations:regen / scripts/regen-extension-migrations.mjs), and example-app migration regen (migrations:regen:examples / scripts/regen-example-migrations.mjs). The example-app migration regen covers the migrations/snapshots/<hex>/contract.* store entries under examples/*/migrations/**. Don't second-guess it by emitting only one package.
fixtures:check gates contract emission, not planner operations. Its diff glob is contract files only (contract.*, expected.contract.json — which also matches every migrations/snapshots/<hex>/contract.* store entry) — ops.json is excluded, and example migration.ts ops are static (regen re-serializes them, never calls plan()). So a green fixtures:check does not prove MigrationPlanner.plan() still emits the same ops. Prove planner-op parity with the planner suites, the migration plan e2e tests, and a golden diff of real plan() output vs the committed example ops. Full mechanism: docs/onboarding/fixtures-emit-and-check.md.
What's forbidden
For any contract.json, contract.d.ts, expected.contract.json, or a migration snapshot store entry (migrations/snapshots/<hex>/contract.{json,d.ts}):
- Writing via
Write,StrReplace,sed,awk, or manual JSON-stringify-then-write. - "Reformatting" the JSON — the canonicalizer owns whitespace and key order.
- Adding/removing fields by hand, even ones a substrate change clearly necessitates.
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.
- 6d ago First seen · 42 lines · 763 tokens per session scan A 06c06838c5e6
never-hand-edit-contract-fixtures is a cursor rule published in the GitHub repository prisma/prisma-next (419 stars, last pushed 11d ago), licensed Apache-2.0. It adds 763 tokens to every session, about $0.0038 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to never-hand-edit-contract-fixtures, differing in 0 lines, and is treated as a copy.
Other cursor rules, from other repositories
control-plane-descriptors
Control plane descriptor and instance implementation patterns.
prefer-assertions-over-defensive-checks
Prefer assertions over defensive checks when data is guaranteed to be valid.
shared-plane-packages
Pattern for creating shared plane packages that serve both migration and runtime planes.
as-contract-cast-smell
// ❌ WRONG — bypasses the family ContractSerializer seam const contract = JSON.parse(raw) as Contract; const contract = JSON.parse(raw) as Contract .
contract-space-package-layout
On-disk layout for packages that expose a contract space (extensions, internal monorepo packages, aggregate-root apps).
directory-layout
Directory layout rules for SQL family vs concrete targets.