cf-scan

name	cf-scan
description	Scan project and populate memory with knowledge — architecture, conventions, tech stack, key features, infrastructure. Use when a project has no memories yet, or when the user wants to refresh/rebuild project understanding — e.g. "scan the project", "scan the codebase", "bootstrap memory", "initialize memory with project knowledge", "populate memory", "build project understanding", "scan this aspect", "analyze the project". This is a token-heavy operation — always warn the user before proceeding.
user-invocable	true
argument-hint	[project description]
model	sonnet
created	"2026-03-16T00:00:00.000Z"
updated	"2026-07-04T00:00:00.000Z"

/cf-scan

CLI Requirement: OPTIONAL — Uses the memory MCP from coding-friend-cli for fast indexed search and storage. Without the CLI: falls back to grep over docs/memory/ and direct file writes. Full functionality preserved, slower memory recall. See CLI requirements.

Scan the project and bootstrap the memory system. User input: $ARGUMENTS

Purpose

New projects start with empty memory. This skill scans the codebase, extracts structured knowledge (architecture, conventions, tech stack, features, infrastructure), and stores it as memories. Safe to run multiple times — existing memories are updated, not duplicated.

Folder

Output goes to {docsDir}/memory/ (default: docs/memory/). Check .coding-friend/config.json for custom docsDir if it exists.

IMPORTANT — path resolution:

• Use MAIN_REPO_ROOT from the SessionStart bootstrap context (injected via session-init.sh). If absent, fall back to running pwd for $CWD and use $CWD as MAIN_REPO_ROOT.
• Read config from CF_CONFIG_FILE (= $MAIN_REPO_ROOT/.coding-friend/config.json) — do NOT search sub-folders
• Use CF_DOCS_ROOT as the docs base dir (= $MAIN_REPO_ROOT/{docsDir} where docsDir comes from config, default docs)
• Always resolve file_path as an absolute path: {CF_DOCS_ROOT}/memory/{category}/{name}.md
• Never use relative paths in write specs — they may resolve incorrectly when the working directory contains nested git repos

Workflow

Step 0: Custom Guide

Custom guide — auto-loaded below (if the raw command shows instead of its output, run it yourself):

bash "${CLAUDE_PLUGIN_ROOT}/lib/load-custom-guide.sh" cf-scan

If output is not empty, integrate returned sections: ## Before → before first step, ## Rules → apply throughout, ## After → after final step.

Step 0.5: Context Budget Check

Before proceeding, assess context budget:

• If context is above 50%, prefer selective reads (Read with offset/limit) over full file reads
• Limit cf-explorer exploration depth — map structure broadly but only deep-read files directly relevant to memory creation
• If context is above 70%, warn the user that scan quality may degrade and suggest running in a fresh session

Step 1: Warn and Confirm

This step is mandatory — do NOT skip.

Tell the user:

This skill scans your project and populates memory. It uses significant tokens (multiple explorer calls + memory writes). Estimated: 3-5 minutes depending on project size.

• Existing memories will be updated, not duplicated
• New memories will be created for discovered knowledge
• Target: ~10-15 memories covering architecture, conventions, features, infrastructure

If $ARGUMENTS is provided, show it back: "I'll use your description to guide the scan: {$ARGUMENTS}"

Ask the user to confirm before proceeding. If they decline, stop.

Read config:

• Read config from CF_CONFIG_FILE (= $MAIN_REPO_ROOT/.coding-friend/config.json) for docsDir (default: docs) and language (default: en)
• Store the project description from $ARGUMENTS (if any) for use in explorer prompts

Step 2: Structural Scan (Phase 1 — Main Agent)

Goal: Build a "project profile" without using any agent calls. This is cheap (Glob + Read only).

2a. Detect key files:

Use Glob to check for these files (read whichever exist):

Category	Files to check
Package/language	package.json, pyproject.toml, Cargo.toml, go.mod, Gemfile, pom.xml, build.gradle, composer.json, mix.exs
Config	tsconfig.json, .eslintrc*, prettier.config*, biome.json, .editorconfig
Infrastructure	Dockerfile, docker-compose.yml, .github/workflows/*.yml, .gitlab-ci.yml, Makefile, Justfile
Documentation	README.md, CONTRIBUTING.md, ARCHITECTURE.md, CLAUDE.md, docs/
Test	jest.config*, vitest.config*, pytest.ini, setup.cfg, .mocharc*, cypress.config*

2b. Read and extract:

Read the detected files (top-level only, not nested). Extract:

• Primary language(s) and framework(s)
• Package manager (npm/yarn/pnpm/pip/cargo/go/etc.)
• Monorepo vs single project (check for workspaces, multiple package.json, etc.)
• Test framework and test patterns
• CI/CD system (GitHub Actions, GitLab CI, etc.)
• Key directories (src/, lib/, app/, etc.)

2c. Build project profile:

Summarize findings as a short "project profile" (keep in your working memory, do not write a file). Example:

Language: TypeScript
Framework: Next.js 14 (App Router)
Package manager: pnpm
Structure: monorepo (3 packages)
Tests: Vitest + Playwright
CI: GitHub Actions
Key dirs: src/app/, src/components/, src/lib/, packages/

Step 3: Deep Scan (Phase 2 — cf-explorer)

Goal: Send 2-4 targeted cf-explorer calls based on the project profile. Each call has a focused scope.

IMPORTANT:

• Include the project profile from Step 2 in every explorer prompt
• Include $ARGUMENTS (user's project description) if provided
• Each explorer must describe features/modules as state machines where applicable: states, transitions, triggers, side effects
• For monorepos with >10 packages, focus on root-level architecture and the 3 most recently modified packages

Explorer calls (launch in parallel where possible):

(a) Architecture & Key Features — always run this one:

Explore this project and map its architecture. Project profile: {profile}. User description: {$ARGUMENTS or "none"}.

For each major module or feature:

1. What it does (purpose, scope)
2. State machine: states → transitions → triggers → side effects
3. Key files and entry points
4. Dependencies (internal and external)

Focus on the top 5-7 most important modules. Do NOT list every file — summarize at the module level.

(b) Conventions & Patterns — always run this one:

Analyze coding conventions and patterns in this project. Project profile: {profile}.

Look for:

1. Naming conventions (files, functions, variables, components)
2. Code organization patterns (barrel exports, index files, co-location)
3. Error handling patterns
4. API/data fetching patterns
5. State management approach
6. Import organization

Be specific — cite actual examples from the code. Do NOT list generic best practices.

(c) Infrastructure & Build — only if CI/Docker/Makefile detected in Step 2:

Analyze the build, deploy, and infrastructure setup. Project profile: {profile}.

Cover:

1. Build pipeline: how code goes from source to production
2. CI/CD: what runs on push/PR, required checks
3. Environment setup: env vars, config files, secrets
4. Docker: what's containerized, multi-stage builds
5. Scripts: key npm scripts or Makefile targets

Describe as a pipeline/state machine: trigger → stages → output.

(d) Domain Concepts — only for projects with rich domain logic (e-commerce, SaaS, APIs with business rules):

Analyze the domain model and business logic. Project profile: {profile}. User description: {$ARGUMENTS or "none"}.

For each core domain entity:

1. What it represents
2. State machine: lifecycle states → transitions → business rules
3. Relationships to other entities
4. Key invariants or validation rules

Focus on domain-specific knowledge that isn't obvious from reading the code structure alone.

Step 4: Synthesize & Store (Phase 3)

Goal: Convert explorer findings into memories. Deduplicate against existing memories.

4a. Get existing memories:

Call memory_list to retrieve all current memories. Build a lookup map: {category}/{slug} → memory object.

4b. Plan memories:

Based on explorer findings, plan ~10-15 memories across categories:

Category	Type	Typical memories
features/	fact	One per major module/feature (3-7 memories)
conventions/	preference	Coding patterns, naming, organization (1-3 memories)
decisions/	context	Architecture choices, tech stack rationale (1-2 memories)
infrastructure/	procedure	Build, deploy, CI/CD setup (1-2 memories)

Memory cap: Maximum 15 memories total. For large projects, merge related modules into broader memories rather than creating one per file.

4c. For each planned memory:

1. Check if a memory with matching {category}/{slug} exists in the lookup map
2. If exists → delegate to cf-writer with task: update and existing_file_action: overwrite, then call memory_update with params: id (e.g. "features/auth-module"), content (full new markdown), tags (updated tags array)
3. If new → assess complexity:
   • Simple (short, factual) → delegate to cf-writer agent (haiku)
   • Complex (nuanced architecture, deep trade-offs) → delegate to cf-writer-deep agent (sonnet)

Write spec for cf-writer (same format as /cf-remember):

Backward compat: When updating existing memory files without a date prefix, preserve the existing filename. Only new files use the YYYY-MM-DD-<name>.md format.

WRITE SPEC
----------
task: create | update
file_path: {CF_DOCS_ROOT}/memory/{category}/YYYY-MM-DD-{name}.md
language: {language from config}
content: |
  ---
  title: "<Title>"
  description: "<One-line summary for grep-based recall, under 100 chars>"
  tags: [tag1, tag2, tag3]
  created: YYYY-MM-DD
  updated: YYYY-MM-DD
  type: "<type based on category>"
  importance: 3
  source: scan
  ---

  # <Title>

  ## Overview
  <1-2 sentences>

  ## Key Points
  - <point>

  ## State Machine
  <If applicable: states, transitions, triggers, side effects>

  ## Details
  <Longer explanation>

  ## Related
  - <key files>
readme_update: false
auto_commit: false
existing_file_action: overwrite

Frontmatter rules:

• source: scan (not "conversation") — this distinguishes scanned memories from manually captured ones
• description must be factual, searchable, under 100 chars
• When updating: set task: update, update updated date, do NOT change created
• existing_file_action: overwrite — scan always replaces full content (not append)

4d. Index via MCP:

After each cf-writer saves a file, call memory_store (for new) or memory_update (for existing) to index in SQLite:

• For memory_store: pass title, description, type, tags, content, importance: 3, source: "scan", index_only: true
• For memory_update: pass id (e.g. "features/auth-module"), content (full markdown body), tags (merged array if changed)

Step 5: Summary

Print a summary table:

## Scan Complete

| # | Category | Title | Action | Description |
|---|----------|-------|--------|-------------|
| 1 | features | Auth Module | created | JWT auth with httpOnly cookies and RS256 |
| 2 | conventions | Naming Patterns | updated | PascalCase components, camelCase utils |
| ... | | | | |

Total: X memories (Y created, Z updated)
Memory DB: indexed ✓ — or: MCP unavailable, files only

Then suggest next steps:

• Run /cf-scan again anytime to refresh project knowledge
• Use /cf-remember to capture specific knowledge from conversations
• Use /cf-ask to query the memory system

Interpreting $ARGUMENTS

$ARGUMENTS is an optional free-form project description. Examples:

• /cf-scan — scan with no additional context
• /cf-scan This is a Next.js e-commerce app with Stripe payments and PostgreSQL — use description to guide scan
• /cf-scan Focus on the API layer and auth system — narrow the scan focus

When provided, include $ARGUMENTS in every explorer prompt so the scan is guided by the user's context.

Rules

• Always warn about token cost before starting (Step 1 is mandatory)
• Cap at 15 memories — merge related topics rather than creating many small memories
• Breadth over depth — cover all major areas rather than going deep on one
• State machines for features — describe features as state machines where applicable
• Idempotent — safe to run multiple times; existing memories are updated, not duplicated
• Skip irrelevant categories — no CI? skip infrastructure/ci. No tests? skip conventions/testing
• Be concise — bullet points over paragraphs
• Include code snippets only when they clarify the point
• Create directories as needed