Official agent skill

Generate Custom Instructions From Codebase

by github in github/awesome-copilot

Migration and code evolution instructions generator for GitHub Copilot.

OfficialMITAuto-check passedDevelopment

Install Generate Custom Instructions From Codebase

skills CLI
$ npx skills add github/awesome-copilot --skill generate-custom-instructions-from-codebase -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install github/awesome-copilot generate-custom-instructions-from-codebase --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/github/awesome-copilot.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/generate-custom-instructions-from-codebase .claude/skills/generate-custom-instructions-from-codebase && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
generate-custom-instructions-from-codebase
GitHub stars
40k
Used in
1 other repo
Token cost
~2.2k tokens
SKILL.md length
207 words
Files
1
Skills in repo
417
Repo updated
First seen
Licence
MIT

At a glance

Migration and code evolution instructions generator for GitHub Copilot.

  • Tasks that involve Refactoring
  • SKILL.md covers Configuration Variables, Generated Prompt, Typical Use Cases and Unique Benefits
  • Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
  • Tasks that involve Code migrations

What it does

Generate Custom Instructions From Codebase is an agent skill from github/awesome-copilot, published by the product's own GitHub organization. Migration and code evolution instructions generator for GitHub Copilot. Analyzes differences between two project versions (branches, commits, or releases) to create precise instructions allowing Copilot to maintain consistency during technology migrations, major refactoring, or framework version upgrades.

Its SKILL.md is about 2.2k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Development, covering Refactoring, Code migrations and Design patterns. The repository describes itself as: Community-contributed instructions, agents, skills, and configurations to help you make the most of GitHub Copilot. The licence is MIT.

When your agent uses it

  • Tasks that involve Refactoring
  • Tasks that involve Code migrations
  • Tasks that involve Design patterns

Example prompts

  • “/generate-custom-instructions-from-codebase”

What it can do on your machine

Read from SKILL.md and the folder at commit 727ff2e. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    No scripts in the folder and no shell commands in SKILL.md.

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Generate Custom Instructions From Codebase loads about 2.2k tokens when it runs. Until then it costs about 87 tokens; SKILL.md has 207 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~87
When it runs · the whole SKILL.md, loaded when a task matches
~2.2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from github/awesome-copilot at commit 727ff2e, republished under its MIT licence (© github). 207 words, ~2,166 tokens.

Download SKILL.mdSave it as .claude/skills/generate-custom-instructions-from-codebase/SKILL.md (or your agent's skills folder).
name
generate-custom-instructions-from-codebase
description
Migration and code evolution instructions generator for GitHub Copilot. Analyzes differences between two project versions (branches, commits, or releases) to create precise instructions allowing Copilot to maintain consistency during technology migrations, major refactoring, or framework version upgrades.

Migration and Code Evolution Instructions Generator

Configuration Variables

${MIGRATION_TYPE="Framework Version|Architecture Refactoring|Technology Migration|Dependencies Update|Pattern Changes"}
<!-- Type of migration or evolution -->

${SOURCE_REFERENCE="branch|commit|tag"}
<!-- Source reference point (before state) -->

${TARGET_REFERENCE="branch|commit|tag"}  
<!-- Target reference point (after state) -->

${ANALYSIS_SCOPE="Entire project|Specific folder|Modified files only"}
<!-- Scope of analysis -->

${CHANGE_FOCUS="Breaking Changes|New Conventions|Obsolete Patterns|API Changes|Configuration"}
<!-- Main aspect of changes -->

${AUTOMATION_LEVEL="Conservative|Balanced|Aggressive"}
<!-- Level of automation for Copilot suggestions -->

${GENERATE_EXAMPLES="true|false"}
<!-- Include transformation examples -->

${VALIDATION_REQUIRED="true|false"}
<!-- Require validation before application -->

Generated Prompt

"Analyze code evolution between two project states to generate precise migration instructions for GitHub Copilot. These instructions will guide Copilot to automatically apply the same transformation patterns during future modifications. Follow this methodology:

### Phase 1: Comparative State Analysis

#### Structural Changes Detection
- Compare folder structure between ${SOURCE_REFERENCE} and ${TARGET_REFERENCE}
- Identify moved, renamed, or deleted files
- Analyze changes in configuration files
- Document new dependencies and removed ones

#### Code Transformation Analysis
${MIGRATION_TYPE == "Framework Version" ? 
  "- Identify API changes between framework versions
   - Analyze new features being used
   - Document obsolete methods/properties
   - Note syntax or convention changes" : ""}

${MIGRATION_TYPE == "Architecture Refactoring" ? 
  "- Analyze architectural pattern changes
   - Identify new abstractions introduced
   - Document responsibility reorganization
   - Note changes in data flows" : ""}

${MIGRATION_TYPE == "Technology Migration" ? 
  "- Analyze replacement of one technology with another
   - Identify functional equivalences
   - Document API and syntax changes
   - Note new dependencies and configurations" : ""}

#### Transformation Pattern Extraction
- Identify repetitive transformations applied
- Analyze conversion rules from old to new format
- Document exceptions and special cases
- Create before/after correspondence matrix

### Phase 2: Migration Instructions Generation

Create a `.github/copilot-migration-instructions.md` file with this structure:

\`\`\`markdown
# GitHub Copilot Migration Instructions

## Migration Context
- **Type**: ${MIGRATION_TYPE}
- **From**: ${SOURCE_REFERENCE} 
- **To**: ${TARGET_REFERENCE}
- **Date**: [GENERATION_DATE]
- **Scope**: ${ANALYSIS_SCOPE}

## Automatic Transformation Rules

### 1. Mandatory Transformations
${AUTOMATION_LEVEL != "Conservative" ? 
  "[AUTOMATIC_TRANSFORMATION_RULES]
   - **Old Pattern**: [OLD_CODE]
   - **New Pattern**: [NEW_CODE]
   - **Trigger**: When to detect this pattern
   - **Action**: Transformation to apply automatically" : ""}

### 2. Transformations with Validation
${VALIDATION_REQUIRED == "true" ? 
  "[TRANSFORMATIONS_WITH_VALIDATION]
   - **Detected Pattern**: [DESCRIPTION]
   - **Suggested Transformation**: [NEW_APPROACH]
   - **Required Validation**: [VALIDATION_CRITERIA]
   - **Alternatives**: [ALTERNATIVE_OPTIONS]" : ""}

### 3. API Correspondences
${CHANGE_FOCUS == "API Changes" || MIGRATION_TYPE == "Framework Version" ? 
  "[API_CORRESPONDENCE_TABLE]
   | Old API   | New API   | Notes     | Example        |
   | --------- | --------- | --------- | -------------- |
   | [OLD_API] | [NEW_API] | [CHANGES] | [CODE_EXAMPLE] | " : ""} |

### 4. New Patterns to Adopt
[DETECTED_EMERGING_PATTERNS]
- **Pattern**: [PATTERN_NAME]
- **Usage**: [WHEN_TO_USE] 
- **Implementation**: [HOW_TO_IMPLEMENT]
- **Benefits**: [ADVANTAGES]

### 5. Obsolete Patterns to Avoid
[DETECTED_OBSOLETE_PATTERNS]
- **Obsolete Pattern**: [OLD_PATTERN]
- **Why Avoid**: [REASONS]
- **Alternative**: [NEW_PATTERN]
- **Migration**: [CONVERSION_STEPS]

## File Type Specific Instructions

${GENERATE_EXAMPLES == "true" ? 
  "### Configuration Files
   [CONFIG_TRANSFORMATION_EXAMPLES]
   
   ### Main Source Files
   [SOURCE_TRANSFORMATION_EXAMPLES]
   
   ### Test Files
   [TEST_TRANSFORMATION_EXAMPLES]" : ""}

## Validation and Security

### Automatic Control Points
- Verifications to perform after each transformation
- Tests to run to validate changes
- Performance metrics to monitor
- Compatibility checks to perform

### Manual Escalation
Situations requiring human intervention:
- [COMPLEX_CASES_LIST]
- [ARCHITECTURAL_DECISIONS]
- [BUSINESS_IMPACTS]

## Migration Monitoring

### Tracking Metrics
- Percentage of code automatically migrated
- Number of manual validations required
- Error rate of automatic transformations
- Average migration time per file

### Error Reporting
How to report incorrect transformations to Copilot:
- Feedback patterns to improve rules
- Exceptions to document
- Adjustments to make to instructions

\`\`\`

### Phase 3: Contextual Examples Generation

${GENERATE_EXAMPLES == "true" ? 
  "#### Transformation Examples
   For each identified pattern, generate:
   
   \`\`\`
   // BEFORE (${SOURCE_REFERENCE})
   [OLD_CODE_EXAMPLE]
   
   // AFTER (${TARGET_REFERENCE}) 
   [NEW_CODE_EXAMPLE]
   
   // COPILOT INSTRUCTIONS
   When you see this pattern [TRIGGER], transform it to [NEW_PATTERN] following these steps: [STEPS]
   \`\`\`" : ""}

### Phase 4: Validation and Optimization

#### Instructions Testing
- Apply instructions on test code
- Verify transformation consistency
- Adjust rules based on results
- Document exceptions and edge cases

#### Iterative Optimization  
${AUTOMATION_LEVEL == "Aggressive" ? 
  "- Refine rules to maximize automation
   - Reduce false positives in detection
   - Improve transformation accuracy
   - Document lessons learned" : ""}

### Final Result

Migration instructions that enable GitHub Copilot to:
1. **Automatically apply** the same transformations during future modifications
2. **Maintain consistency** with newly adopted conventions  
3. **Avoid obsolete patterns** by automatically proposing alternatives
4. **Accelerate future migrations** by capitalizing on acquired experience
5. **Reduce errors** by automating repetitive transformations

These instructions transform Copilot into an intelligent migration assistant, capable of reproducing your technology evolution decisions consistently and reliably.
"

Typical Use Cases

Framework Version Migration

Perfect for documenting the transition from Angular 14 to Angular 17, React Class Components to Hooks, or .NET Framework to .NET Core. Automatically identifies breaking changes and generates corresponding transformation rules.

Technology Stack Evolution

Essential when replacing a technology entirely: jQuery to React, REST to GraphQL, SQL to NoSQL. Creates a comprehensive migration guide with pattern mappings.

Architecture Refactoring

Ideal for large refactorings like Monolith to Microservices, MVC to Clean Architecture, or Component to Composable architecture. Preserves architectural knowledge for future similar transformations.

Design Pattern Modernization

Useful for adopting new patterns: Repository Pattern, Dependency Injection, Observer to Reactive Programming. Documents the rationale and implementation differences.

Unique Benefits

🧠 Artificial Intelligence Enhancement

Unlike traditional migration documentation, these instructions "train" GitHub Copilot to reproduce your technology evolution decisions automatically during future code modifications.

🔄 Knowledge Capitalization

Transforms specific project experience into reusable rules, avoiding the loss of migration expertise and accelerating future similar transformations.

🎯 Context-Aware Precision

Instead of generic advice, generates instructions tailored to your specific codebase, with real before/after examples from your project evolution.

⚡ Automated Consistency

Ensures that new code additions automatically follow the new conventions, preventing architectural regression and maintaining code evolution coherence.

© github, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in skills/generate-custom-instructions-from-codebase of github/awesome-copilot.

Open the folder on GitHubat commit 727ff2e

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in github/awesome-copilot, which our catalogue first saw on October 7, 2026.

Compare with similar skills

Generate Custom Instructions From Codebase next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Generate Custom Instructions From Codebase compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
Generate Custom Instructions From Codebase this skillgithub/awesome-copilot40k1 repos~2.2kAutomated safety check: PassMIT
Migrate Core Code to Submodulestinyhumansai/openhuman41k—~2.6kAutomated safety check: PassGPL-3.0
ast-grep Structural Searchcode-yeongyu/oh-my-openagent70k—~3.3kAutomated safety check: PassMIT
Swiftui View RefactorDimillian/Skills4k5 repos~2kAutomated safety check: PassMIT
RTK Rust Design Patternsrtk-ai/rtk83k—~1.9kAutomated safety check: PassApache-2.0
Architecture PatternsKartikLabhshetwar/better-shot2.4k2 repos~1.4kAutomated safety check: PassCustom licence

Similar skills

  • Migrate Core Code to Submodules

    tinyhumansai/openhuman

    Plans and carries out moving non-host-specific code and its tests from the OpenHuman core into vendored tiny submodule libraries, then releases the submodule and re-pins the host.

    41k GitHub stars~2.6k tokensUpdated yesterday
    DevelopmentAuto-check passed
  • ast-grep Structural Search

    code-yeongyu/oh-my-openagent

    Searches and rewrites code by syntax-tree shape across 25 languages with ast-grep, for codemods, structural queries and YAML lint rules, using a Python wrapper script.

    70k GitHub stars~3.3k tokensUpdated yesterday
    DevelopmentAuto-check passed
  • Swiftui View Refactor

    Dimillian/Skills

    Refactor and review SwiftUI view files with strong defaults for small dedicated subviews, MV-over-MVVM data flow, stable view trees, explicit dependency injection, and correct Observation usage.

    4k GitHub starsUsed in 5 repos~2k tokens
    DevelopmentAuto-check passed
  • Describes seven Rust design patterns for the RTK CLI filter modules, with when to use each, RTK examples, and notes on when a pattern is overkill.

    83k GitHub stars~1.9k tokensUpdated yesterday
    DevelopmentAuto-check passed
  • Architecture Patterns

    KartikLabhshetwar/better-shot

    Deep dive into software architecture for macOS. An agent skill from KartikLabhshetwar/better-shot.

    2.4k GitHub starsUsed in 2 repos~1.4k tokens
    DevelopmentAuto-check passed
  • Official

    Replaces a plain TypeScript union plus switch statements with frozen subclasses and a visitor interface when several places dispatch on the same variants.

    48k GitHub stars~830 tokensUpdated yesterday
    DevelopmentAuto-check passed

More from github/awesome-copilot

All 417 skills in this repo
  • Acquire Codebase Knowledge

    github/awesome-copilot

    Official

    Maps an unfamiliar codebase into seven evidence-backed documents in docs/codebase/, using a scan script and templates, for onboarding or architecture write-ups.

    40k GitHub starsUsed in 1 repo~2.3k tokens
    Auto-check passed
  • Azure Architecture Autopilot

    github/awesome-copilot

    Official

    Designs Azure infrastructure from a natural-language description, or diagrams an existing resource group, then refines the design through conversation and deploys it with Bicep.

    40k GitHub starsUsed in 1 repo~1.9k tokens
    Auto-check passed
  • Draw.io Diagram Generator

    github/awesome-copilot

    Official

    Generates, edits and validates draw.io files with correct mxGraph XML, covering flowcharts, architecture, sequence, ER and UML class diagrams.

    40k GitHub starsUsed in 1 repo~4.9k tokens
    Auto-check passed
  • Credit Risk Data Cleaning

    github/awesome-copilot

    Official

    Cleans raw credit data and screens variables before loan modeling, dropping unstable, noisy or redundant features and writing an Excel report of every step.

    40k GitHub starsUsed in 1 repo~1.5k tokens
    Auto-check passed
  • Daily Focus Board

    github/awesome-copilot

    Official

    Builds a warm, browser-based daily focus board the user updates by talking to their agent, with Eisenhower priorities, a brain-dump box and kind not-today carryover.

    40k GitHub stars~3k tokensUpdated yesterday
    Auto-check passed
  • Python Pypi Package Builder

    github/awesome-copilot

    Official

    End-to-end skill for building, testing, linting, versioning, and publishing a production-grade Python library to PyPI.

    40k GitHub starsUsed in 1 repo~4.6k tokens
    Auto-check passed

Categories

Questions about Generate Custom Instructions From Codebase

What does Generate Custom Instructions From Codebase do?

Migration and code evolution instructions generator for GitHub Copilot. Generate Custom Instructions From Codebase is an agent skill from github/awesome-copilot, published by the product's own GitHub organization. Migration and code evolution instructions generator for GitHub Copilot.

When should I use Generate Custom Instructions From Codebase?

Generate Custom Instructions From Codebase fits situations like: tasks that involve Refactoring; tasks that involve Code migrations; tasks that involve Design patterns.

How do I install Generate Custom Instructions From Codebase in Claude Code?

Run `npx skills add github/awesome-copilot --skill generate-custom-instructions-from-codebase -a claude-code`. Or copy the skill folder (skills/generate-custom-instructions-from-codebase in github/awesome-copilot) into .claude/skills/generate-custom-instructions-from-codebase in your project. Claude Code loads it when a task matches its description.

How do I install Generate Custom Instructions From Codebase in Codex?

Run `npx skills add github/awesome-copilot --skill generate-custom-instructions-from-codebase -a codex`. Or copy the skill folder (skills/generate-custom-instructions-from-codebase in github/awesome-copilot) into .agents/skills/generate-custom-instructions-from-codebase in your project. Codex loads it when a task matches its description.

Can I use Generate Custom Instructions From Codebase in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add github/awesome-copilot --skill generate-custom-instructions-from-codebase -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/generate-custom-instructions-from-codebase, .gemini/skills/generate-custom-instructions-from-codebase, .github/skills/generate-custom-instructions-from-codebase and .opencode/skills/generate-custom-instructions-from-codebase in your project.

What does Generate Custom Instructions From Codebase need to run?

SKILL.md names no scripts, command-line tools or credentials: Generate Custom Instructions From Codebase is instructions for the agent only.

Does Generate Custom Instructions From Codebase access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Generate Custom Instructions From Codebase safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Generate Custom Instructions From Codebase use?

Generate Custom Instructions From Codebase is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Generate Custom Instructions From Codebase use?

About 2.2k tokens (SKILL.md is roughly 8.7k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Generate Custom Instructions From Codebase?

Skills that share tags, products or a category with Generate Custom Instructions From Codebase: Migrate Core Code to Submodules (tinyhumansai/openhuman, 41k stars), ast-grep Structural Search (code-yeongyu/oh-my-openagent, 70k stars), Swiftui View Refactor (Dimillian/Skills, 4k stars) and RTK Rust Design Patterns (rtk-ai/rtk, 83k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Generate Custom Instructions From Codebase?

github (a GitHub organization, an official publisher) maintains it in github/awesome-copilot, which has 39,748 GitHub stars. The repository holds 417 skills in this directory. The repository was last updated on October 7, 2026.

Source: github/awesome-copilot on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.