B5 Dedicated Development Agents

💡 One-line summary: Create dedicated development agents like Code Reviewer, Security Auditor, and Test Writer.

📝 Course Notes

Key takeaways from this lesson:

B5 Dedicated Development Agents - Course Notes

What You'll Be Able to Do

Create a Code Reviewer Agent
Create a Security Auditor Agent
Create a Test Writer Agent
Combine multiple agents into a development workflow

Your Current Pain Points

You have to do code review, security checks, and test generation yourself
You need to tell the AI what standards to use for review every time
You want multiple "experts" to collaborate but don't know how to implement it

When to Use This Technique

When you need: Use specialized agents to improve development quality
And you don't want: Repeatedly input review standards every time

🎒 Prerequisites

Make sure you've completed the following:

[ ] Completed B1 Development Daily
[ ] Completed 3.2 Understanding Agents

Core Concept

Development Agent Matrix

Agent	Responsibility	Use Case
Code Reviewer	Code review	PR review, self-check
Security Auditor	Security audit	Pre-release check
Test Writer	Test generation	Test coverage supplement
Doc Writer	Documentation	Comments, README

Follow Along

Step 1: Create Code Reviewer Agent

Why
A professional code review agent can discover more issues.

bash

mkdir -p ~/.config/opencode/agent

Agent configuration file locations:
Global: ~/.config/opencode/agent/
Project-level: .opencode/agent/
The agent's invocation name defaults to the filename: for example, code-reviewer.md corresponds to @code-reviewer.

Create the configuration:

Help me create a Code Reviewer Agent, save to ~/.config/opencode/agent/code-reviewer.md:

---
description: Strict code review expert
mode: subagent
model: anthropic/claude-opus-4-5-thinking
temperature: 0.3
permission:
  edit: deny
  bash: deny
---


# Code Reviewer Agent

You are an experienced senior engineer specializing in code review.

## Review Checklist

### Code Quality
- [ ] Single responsibility per function
- [ ] Clear and accurate naming
- [ ] No duplicate code
- [ ] Appropriate comments

### Potential Issues
- [ ] Boundary condition handling
- [ ] Complete error handling
- [ ] No memory leak risks
- [ ] No race conditions

### Maintainability
- [ ] Code is easy to understand
- [ ] Good testability
- [ ] Follows project conventions

## Output Format

For each issue, output in the following format:
- **Location**: filename:line_number
- **Issue**: description of the problem
- **Severity**: High / Medium / Low
- **Suggestion**: fix recommendation

Sources (Agent Markdown field and tools syntax examples):

opencode/packages/web/src/content/docs/agents.mdx:163
opencode/packages/web/src/content/docs/agents.mdx:167
opencode/packages/web/src/content/docs/agents.mdx:169

Step 2: Create Security Auditor Agent

Why
Security audits require a specialized perspective.

Help me create a Security Auditor Agent, save to ~/.config/opencode/agent/security-auditor.md:

---
description: Security vulnerability hunter
mode: subagent
model: anthropic/claude-opus-4-5-thinking
temperature: 0.2
permission:
  edit: deny
  bash: deny
---

# Security Auditor Agent

You are a security expert specializing in discovering security vulnerabilities in code.

## Check Items

### Input Validation
- SQL injection
- XSS attacks
- Command injection
- Path traversal

### Authentication & Authorization
- Authentication bypass
- Privilege escalation
- Session management

### Sensitive Data
- Hardcoded secrets
- Sensitive information leakage
- Insecure storage

### Dependency Security
- Known vulnerable dependencies
- Outdated package versions

## Output Format

For each security issue:
- **Vulnerability Type**: OWASP classification
- **Location**: filename:line_number
- **Risk Level**: Critical/High/Medium/Low
- **Description**: vulnerability description
- **Fix Suggestion**: how to fix
- **Reference**: relevant CWE/CVE

Step 3: Create Test Writer Agent

Why
A dedicated test agent can generate more comprehensive tests.

Help me create a Test Writer Agent, save to ~/.config/opencode/agent/test-writer.md:

---
description: Test case expert
mode: subagent
model: anthropic/claude-opus-4-5-thinking
temperature: 0.4
permission:
  edit: deny
  bash: deny
---

# Test Writer Agent

You are a testing expert skilled at designing and writing test cases.

## Test Strategy

1. **Unit Tests**: Isolate and test each function
2. **Integration Tests**: Test module interactions
3. **Boundary Tests**: Test boundary conditions
4. **Exception Tests**: Test error handling

## Test Coverage

Each function must cover:
- Normal inputs
- Boundary values (max, min, threshold)
- Invalid inputs (null, undefined, wrong type)
- Exception cases (network errors, timeouts)

## Output Format

Use the project's test framework to generate runnable test code.

Step 4: Use Dedicated Agents

Why
Invoke dedicated agents to complete tasks.

Restart OpenCode:

bash

opencode

Invoke Code Reviewer:

@code-reviewer @src/services/auth.ts Please review this authentication module

Invoke Security Auditor:

@security-auditor @src/controllers/ Perform a security audit on this directory

Invoke Test Writer:

@test-writer @src/utils/validate.ts Generate complete test cases for this file

Step 5: Combine into a Workflow

Why
Multiple agents working together is more efficient.

Create a comprehensive review command .opencode/command/comprehensive-review.md:

---
description: Comprehensive code review
---

Please execute in order:
1. @code-reviewer review code quality
2. @security-auditor check security risks
3. @test-writer analyze test coverage

Target file: $ARGUMENTS

Finally, summarize all issues and sort by priority.

Sources (custom command directory and parameter placeholder):

opencode/packages/web/src/content/docs/commands.mdx:20
opencode/packages/web/src/content/docs/commands.mdx:113
opencode/packages/opencode/src/config/config.ts:191
opencode/packages/opencode/src/command/index.ts:49

Usage:

/comprehensive-review src/services/payment.ts

Checkpoint ✅

Must pass all items to continue

[ ] Created Code Reviewer Agent
[ ] Created Security Auditor Agent
[ ] Created Test Writer Agent
[ ] Can invoke with @agent-name

Common Pitfalls

Symptom	Cause	Solution
@agent-name doesn't respond	Invocation name doesn't match filename (or typo)	Confirm filename (without .md) is the invocation name, e.g., `code-reviewer.md` → `@code-reviewer`
Agent configuration doesn't take effect	Config file not in agent directory	Put in `~/.config/opencode/agent/` (global) or `.opencode/agent/` (project-level)
Multiple agents give inconsistent results	Each executes independently	Chain with command and summarize together

Lesson Summary

You learned:

Create Code Reviewer Agent
Create Security Auditor Agent
Create Test Writer Agent
Combine multiple agents into a workflow

Next Lesson Preview

Next lesson we'll learn B6 Intranet/Offline Deployment.
You'll learn:
Run OpenCode in enterprise intranet environment
Disable all external network requests
Configure internal AI gateway

B5 Dedicated Development Agents ​

📝 Course Notes ​

What You'll Be Able to Do ​

Your Current Pain Points ​

When to Use This Technique ​

🎒 Prerequisites ​

Core Concept ​

Development Agent Matrix ​

Follow Along ​

Step 1: Create Code Reviewer Agent ​

Step 2: Create Security Auditor Agent ​

Step 3: Create Test Writer Agent ​

Step 4: Use Dedicated Agents ​

Step 5: Combine into a Workflow ​

Checkpoint ✅ ​

Common Pitfalls ​

Lesson Summary ​

Next Lesson Preview ​