Borrowing it
Nothing to install: this file belongs to Andes-Software-Solutions/Andes.Extensions.AI. 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/Andes-Software-Solutions/Andes.Extensions.AI/main/.claude/skills/ef-core/SKILL.mdgit clone --depth 1 https://github.com/Andes-Software-Solutions/Andes.Extensions.AIWrote 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/andes-software-solutions/andes.extensions.ai/ef-core)<a href="https://agentmods.dev/skills/andes-software-solutions/andes.extensions.ai/ef-core"><img src="https://agentmods.dev/badge/skills/andes-software-solutions/andes.extensions.ai/ef-core.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 | $0.00010 | $0.00499 |
| Opus 5 | $0.00005 | $0.00249 |
| Sonnet 5 | $0.00002 | $0.00100 |
| Haiku 4.5 | $0.00001 | $0.00050 |
Grade A, and why
ef-core 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 8d 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 ef-core — 1 line 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 — 75 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Entity Framework Core Best Practices
Your goal is to help me follow best practices when working with Entity Framework Core.
Data Context Design
- Keep DbContext classes focused and cohesive
- Use constructor injection for configuration options
- Override OnModelCreating for fluent API configuration
- Separate entity configurations using IEntityTypeConfiguration
- Consider using DbContextFactory pattern for console apps or tests
Entity Design
- Use meaningful primary keys (consider natural vs surrogate keys)
- Implement proper relationships (one-to-one, one-to-many, many-to-many)
- Use data annotations or fluent API for constraints and validations
- Implement appropriate navigational properties
- Consider using owned entity types for value objects
Performance
- Use AsNoTracking() for read-only queries
- Implement pagination for large result sets with Skip() and Take()
- Use Include() to eager load related entities when needed
- Consider projection (Select) to retrieve only required fields
- Use compiled queries for frequently executed queries
- Avoid N+1 query problems by properly including related data
Migrations
- Create small, focused migrations
- Name migrations descriptively
- Verify migration SQL scripts before applying to production
- Consider using migration bundles for deployment
- Add data seeding through migrations when appropriate
Querying
- Use IQueryable judiciously and understand when queries execute
- Prefer strongly-typed LINQ queries over raw SQL
- Use appropriate query operators (Where, OrderBy, GroupBy)
- Consider database functions for complex operations
- Implement specifications pattern for reusable queries
Change Tracking & Saving
- Use appropriate change tracking strategies
- Batch your SaveChanges() calls
- Implement concurrency control for multi-user scenarios
- Consider using transactions for multiple operations
- Use appropriate DbContext lifetimes (scoped for web apps)
Security
- Avoid SQL injection by using parameterized queries
- Implement appropriate data access permissions
- Be careful with raw SQL queries
- Consider data encryption for sensitive information
- Use migrations to manage database user permissions
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.
- 8d ago First seen · 75 lines · 10 tokens per session scan A cab5bc6e7168
ef-core is a skill published in the GitHub repository Andes-Software-Solutions/Andes.Extensions.AI (9 stars, last pushed 5d ago), licensed MIT. It adds 10 tokens to every session and 499 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to ef-core, differing in 1 line, and is treated as a copy.
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