Apply Pattern

What it does

When your agent uses it

• Asks to apply a pattern
• Use a blueprint
• Implement [pattern] from [source]
• What blueprints do I have

Example prompts

• “apply a pattern”
• “use a blueprint”
• “implement [pattern] from [source]”
• “/apply-pattern”

Requirements

• Node.js
• Compatibility (from SKILL.md): Requires grepika MCP server.
• Pre-approved tools (allowed-tools): mcp__grepika__search, mcp__grepika__refs, mcp__grepika__outline, mcp__grepika__toc, mcp__grepika__get, mcp__grepika__structural_search, mcp__grepika__add_workspace, Bash, Read

Workflow steps

4 steps, taken from the step headings in SKILL.md.

1. 1Read the Pattern
2. 2Understand the Current Project
3. 3Adapt the Pattern
4. 4Provide Implementation Guidance

What it can do on your machine

Read from SKILL.md and the folder at commit f035a18. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • mcp__grepika__search
  • mcp__grepika__refs
  • mcp__grepika__outline
  • mcp__grepika__toc
  • mcp__grepika__get
  • mcp__grepika__structural_search
  • mcp__grepika__add_workspace
  • Bash
  • Read

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are bash).

  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.

• Compatibility

  Requires grepika MCP server.

  From compatibility in the SKILL.md frontmatter.

Context cost

Apply Pattern loads about 1.4k tokens when it runs. Until then it costs about 79 tokens; SKILL.md has 398 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~79

When it runs · the whole SKILL.md, loaded when a task matches

~1.4k

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

• NotePre-approves every shell command (allowed-tools: Bash)SKILL.md

  allowed-tools: mcp__grepika__search, mcp__grepika__refs, mcp__grepika__outline, mcp__grepika__toc, mcp__grepika__ge

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 adamthewilliam/grepika at commit f035a18, republished under its MIT licence (© adamthewilliam). 398 words, ~1,416 tokens.

name

apply-pattern

description

This skill should be used when the user asks to "apply a pattern", "use a blueprint", "implement [pattern] from [source]", "what blueprints do I have", "list patterns", "adapt this pattern", or mentions keywords related to applying previously extracted architectural patterns to their current project.

allowed-tools

mcp__grepika__search, mcp__grepika__refs, mcp__grepika__outline, mcp__grepika__toc, mcp__grepika__get, mcp__grepika__structural_search, mcp__grepika__add_workspace, Bash, Read

compatibility

Requires grepika MCP server.

version

1.0.0

disable-model-invocation

true

context

fork

agent

Explore

model

haiku

ls -1 ~/.claude/blueprints/ 2>/dev/null || echo "No blueprints found. Use /study to extract patterns from a codebase first."

head -10 ~/.claude/blueprints/*/blueprint.md

## Available Blueprints

| Source | Patterns | Studied | Focus |
|--------|----------|---------|-------|
| [name] | [count] | [date] | [focus] |

Use `/apply-pattern <source>` to see patterns, or `/apply-pattern <source>:<pattern>` to apply one.

## Patterns in [source]

| # | Pattern | Load-bearing | Category |
|---|---------|-------------|----------|
| 1 | [name] | yes/no | [category] |

### Build Order
[from the blueprint's Build Order section]

Use `/apply-pattern [source]:[pattern-name]` to apply a pattern.

## Applying Pattern: [pattern-name]
> From blueprint: [source]

### Pattern Summary
[What/Why from the blueprint — brief]

### Your Project Context
- **Language**: [target language/framework]
- **Relevant existing code**: [files/symbols that relate to this pattern]
- **What you already have**: [any partial implementation that exists]
- **What's missing**: [what needs to be built]

### Adaptation Plan

#### Step 1: [first thing to implement]
**Where**: `path/to/file.ext`
**What**: [specific guidance]
**Source reference**: [what the source codebase does at this point]

#### Step 2: [next thing]
...

### Key Differences from Source
| Aspect | Source ([source]) | Your Project |
|--------|-------------------|--------------|
| [aspect] | [source approach] | [recommended approach] |

### Dependencies to Add
| Package | Purpose | Alternative |
|---------|---------|-------------|
| [name] | [why needed] | [alternative if any] |

### What to Watch For
- [pitfall or edge case from the source pattern]
- [adaptation concern specific to the target project]

grep -rl "## Pattern: .*<pattern>" ~/.claude/blueprints/*/blueprint.md 2>/dev/null

© adamthewilliam, 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 plugins/grepika/skills/apply-pattern of adamthewilliam/grepika.

Open the folder on GitHubat commit f035a18