Skill: Capture Lesson Learned

Overview

This skill captures a lesson learned when closing a finding. It is MANDATORY - you cannot close findings without capturing what was learned.

CRITICAL ENFORCEMENT: This skill enforces knowledge retention. Every closed finding MUST have an associated lesson.

Purpose

Per workflow requirement: "When a finding is closed, the workflow must enforce documenting what was learned."

This prevents:

• Knowledge loss when team members leave
• Repeated mistakes across features
• Loss of problem-solving context

When to Use

• When closing any finding
• When resolving a bug or issue
• When completing a phase with findings
• When user explicitly requests lesson capture

Execution Flow

1. VALIDATE required fields
2. CREATE LessonLearned object
3. SAVE to templates/lessons-learned.md
4. LINK to finding
5. CONFIRM capture complete

Required Parameters

Parameter	Type	Description	Required
findingId	string	ID of the finding being closed	Yes
category	enum	Technical, Process, Communication, Tooling	Yes
title	string	Brief title of the lesson (max 80 chars)	Yes
description	string	What was the issue?	Yes
rootCause	string	Why did this happen?	Yes
solution	string	How was it resolved?	Yes
preventionSteps	string[]	Steps to prevent recurrence	Yes
tags	string[]	Tags for categorization	No
priority	enum	Critical, High, Medium, Low	No (default: High)

Lesson Categories

Category	Description	Example
Technical	Code, architecture, infrastructure	"Always validate API responses"
Process	Workflow, methodology, procedures	"Review PRs before merging"
Communication	Documentation, collaboration	"Document API changes in changelog"
Tooling	Build tools, CI/CD, frameworks	"Pin dependency versions"

Output Format

## Lesson Captured: [Title]

- **ID:** LESSON-[timestamp]-[random]
- **Finding:** [findingId]
- **Category:** [category]
- **Priority:** [priority]
- **Captured:** [timestamp]

### Problem
[description]

### Root Cause
[rootCause]

### Solution
[solution]

### Prevention Steps
1. [step 1]
2. [step 2]
...

### Tags
[tag1], [tag2], ...

---
*This lesson has been saved to templates/lessons-learned.md*

Example Usage

Example 1: Capturing a Technical Lesson

USER: I fixed the SQL injection vulnerability in the user search feature.

[Agent captures lesson]

SKILL INPUT:
{
  "findingId": "FIND-2026-0217-001",
  "category": "Technical",
  "title": "SQL Injection in User Search",
  "description": "User search feature was vulnerable to SQL injection attacks through the name parameter",
  "rootCause": "Direct string concatenation in SQL query instead of parameterized queries",
  "solution": "Replaced string concatenation with parameterized queries using the ORM",
  "preventionSteps": [
    "Always use parameterized queries for database operations",
    "Never trust user input - always sanitize",
    "Run SQL injection scans in CI/CD pipeline"
  ],
  "tags": ["security", "sql", "injection", "database"],
  "priority": "Critical"
}

SKILL OUTPUT:
## Lesson Captured: SQL Injection in User Search

- **ID:** LESSON-20260217-a1b2c3d4
- **Finding:** FIND-2026-0217-001
- **Category:** Technical
- **Priority:** Critical
- **Captured:** 2026-02-17T11:30:00Z

### Problem
User search feature was vulnerable to SQL injection attacks through the name parameter

### Root Cause
Direct string concatenation in SQL query instead of parameterized queries

### Solution
Replaced string concatenation with parameterized queries using the ORM

### Prevention Steps
1. Always use parameterized queries for database operations
2. Never trust user input - always sanitize
3. Run SQL injection scans in CI/CD pipeline

### Tags
security, sql, injection, database

---
*This lesson has been saved to templates/lessons-learned.md*

Example 2: Capturing a Process Lesson

USER: The build failed because we forgot to update the lock file.

SKILL INPUT:
{
  "findingId": "FIND-2026-0217-002",
  "category": "Process",
  "title": "Package Lock File Not Updated",
  "description": "Build failed because package-lock.json was not updated after adding new dependency",
  "rootCause": "Developer added dependency but did not commit lock file changes",
  "solution": "Added pre-commit hook to verify lock file is updated when package.json changes",
  "preventionSteps": [
    "Always commit lock file when changing package.json",
    "Run npm ci instead of npm install in CI",
    "Add pre-commit hook to check for lock file sync"
  ],
  "tags": ["build", "npm", "dependencies", "ci"],
  "priority": "Medium"
}

Enforcement Rules

1. MANDATORY: All findings must have lessons captured before closing
2. BLOCKING: Phase transition is blocked if findings closed without lessons
3. PERSISTENCE: Lessons are saved to templates/lessons-learned.md
4. DISCOVERY: Lessons are checked by check-lessons skill before agent work

Integration with Workflow

FINDING CREATED → ASSIGNED → RESOLVED → [CAPTURE LESSON] → CLOSED
                                            ↑
                                    MANDATORY STEP

Error Messages

Error	Cause	Resolution
"Finding ID required"	No findingId provided	Provide the finding ID
"Description required"	Empty description	Describe what the issue was
"Root cause required"	Empty rootCause	Explain why this happened
"Solution required"	Empty solution	Explain how it was fixed
"Prevention steps required"	Empty preventionSteps	List steps to prevent recurrence
"Invalid category"	Category not in enum	Use: Technical, Process, Communication, Tooling

Files Modified

• templates/lessons-learned.md - Lessons are appended here
• findings.md - Finding updated with lesson reference
• .devflow/context-checkpoint.md - Included in context checkpoints