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/object-hasowngit clone --depth 1 https://github.com/prisma/prisma-nextWhat 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 | $0.00000 | $0.00301 |
| Opus 5 | $0.00000 | $0.00151 |
| Sonnet 5 | $0.00000 | $0.00060 |
| Haiku 4.5 | $0.00000 | $0.00030 |
Grade A, and why
object-hasown 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 2d 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 object-hasown — 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
Use Object.hasOwn() Instead of hasOwnProperty()
CRITICAL: Always use Object.hasOwn() instead of hasOwnProperty() to check for own properties.
Why?
Object.hasOwn()is the modern, recommended API (ES2022)hasOwnProperty()can be overridden or shadowed- Biome lint rule
noPrototypeBuiltinsenforces this
Examples
❌ WRONG: Using hasOwnProperty()
if (obj.hasOwnProperty('key')) { /* ... */ }
if (meta.annotations?.codecs?.hasOwnProperty('id')) { /* ... */ }
✅ CORRECT: Using Object.hasOwn()
if (Object.hasOwn(obj, 'key')) { /* ... */ }
if (Object.hasOwn(meta.annotations?.codecs ?? {}, 'id')) { /* ... */ }
Note: When using optional chaining, provide a fallback object:
// ❌ WRONG
Object.hasOwn(meta.annotations?.codecs, 'id') // May pass undefined
// ✅ CORRECT
Object.hasOwn(meta.annotations?.codecs ?? {}, 'id')
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.
- 2d ago First seen · 39 lines · 0 tokens per session scan A 7c05c8e8f830
object-hasown is a cursor rule published in the GitHub repository prisma/prisma-next (421 stars, last pushed 7d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 301 tokens. A static security scan graded it A with 0 findings. It is 100% identical to object-hasown, differing in 0 lines, and is treated as a copy.
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