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.
git 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/type-predicates)<a href="https://agentmods.dev/rules/prisma/prisma-next/type-predicates"><img src="https://agentmods.dev/badge/rules/prisma/prisma-next/type-predicates/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/rules/prisma/prisma-next/type-predicates"><img src="https://agentmods.dev/badge/rules/prisma/prisma-next/type-predicates.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 | $0.00000 | $0.00251 |
| Opus 5.5 | $0.00000 | $0.00100 |
| Sonnet 5.5 | $0.00000 | $0.00050 |
| Haiku 4.5 | $0.00000 | $0.00025 |
Grade A, and why
type-predicates 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 1mo 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 type-predicates — 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.
What it actually says
Type Predicates (Replace Blind Casts)
Rule: Blind casts like as unknown as X are forbidden in production code.
Prefer:
- Type predicates (
value is X) / type guards - Refactoring the type surface so the compiler can do the narrowing
Example
type ColumnBuilder = { kind: 'column'; table: string; column: string };
export function isColumnBuilder(value: unknown): value is ColumnBuilder {
return (
typeof value === 'object' &&
value !== null &&
'kind' in value &&
(value as { kind: unknown }).kind === 'column'
);
}
Tests-only exception
In *.test.ts / *.test-d.ts, double casts can be acceptable for mocks/dynamic proxies, but:
- Use
unknown(notany) - Keep the cast local and explained
- Don’t copy the pattern into production code
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.
- 1mo ago First seen · 37 lines · 0 tokens per session scan A f699f6a382da
type-predicates is a cursor rule published in the GitHub repository prisma/prisma-next (412 stars, last pushed 2mo ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 251 tokens. A static security scan graded it A with 0 findings. It is 100% identical to type-predicates, differing in 0 lines, and is treated as a copy.
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