DevPlan MCP Server

Transform ideas into executable development plans — an MCP server that brings the ClaudeCode-DevPlanBuilder methodology to Claude Code.

> The Problem: AI coding assistants often lose context, skip steps, or produce inconsistent code across sessions.
>
> The Solution: DevPlan creates detailed, agent-executable development plans with built-in validation, lessons learned, and inline git workflows.

---

NEW — Install as a Skill (No MCP Server Required)

DevPlan is now available as a standalone Claude Code skill — no MCP server, no network dependency, no SSE timeouts. The entire DevPlan methodology runs locally as a first-class plugin.

Install

Step 1 — Add this repo as a plugin marketplace:

/plugin marketplace add mmorris35/devplan-mcp-server

Step 2 — Install the plugin at user scope (available across all projects):

/plugin install devplan@mmorris35 --scope user

Step 3 — Reload plugins to activate:

/reload-plugins

Usage

Invoke the skill directly:

/devplan

Or use specific sub-commands:

/devplan brief          — Create or parse a PROJECT_BRIEF.md
/devplan plan           — Generate a Haiku-executable DEVELOPMENT_PLAN.md
/devplan agents         — Generate executor (Haiku) and verifier (Sonnet) agents
/devplan claude-md      — Generate a project CLAUDE.md
/devplan validate       — Check plan structure and Haiku-executability
/devplan progress       — Show completion status
/devplan export mermaid — Generate a Mermaid flowchart of the plan
/devplan issue <number> — Convert a GitHub issue to a remediation task
/devplan implement      — Kickoff the build with executor + verifier agents

Or just describe what you need — Claude will invoke the skill automatically:

"Help me plan a CLI tool for managing dotfiles"
"Create a development plan for this project"
"Validate my development plan"

What's Included

skills/devplan/
├── SKILL.md                 — Core methodology, interview flow, dispatch
├── references/
│   ├── templates.md         — Brief/plan/CLAUDE.md templates (CLI, web app, API, library)
│   ├── validation.md        — Structure + Haiku-executability rules + battle-tested lessons
│   ├── agents.md            — Executor and verifier agent generation patterns
│   └── workflows.md         — Mermaid/ReactFlow export + progress tracking
├── scripts/
│   ├── validate-plan.sh     — Structural validation (standalone)
│   └── check-haiku.sh       — Haiku-executability checker (standalone)
└── examples/
    └── hello-cli-plan.md    — Gold standard reference plan

Skill vs MCP Server

| | Skill (NEW) | MCP Server |
|---|---|---|
| Network | None required | SSE connection to Cloudflare |
| Reliability | Always works | Subject to SSE timeouts |
| Lessons system | Use Nellie or your own | Built-in KV store |
| Install | /plugin install | claude mcp add |
| Validation scripts | Standalone bash | Server-side |

Both options are fully supported. The skill is recommended for reliability; the MCP server adds the lessons learned system and usage analytics.

---

Key Features

| Feature | Description |
|---------|-------------|
| Agent-Executable Plans | Plans so detailed that any LLM coding agent can execute them mechanically |
| Built-in Validation | Validates plans are complete before execution begins |
| Real-Time Progress Tracking | Integrates with Claude Code's Task tools for live visibility |
| Lessons Learned | Captures issues from verification and injects them into future plans |
| Issue Remediation | Converts GitHub issues directly into remediation tasks |
| Executor & Verifier Agents | Auto-generates specialized agents with task tracking built-in |

Install

claude mcp add devplan --transport sse https://mcp.devplanmcp.store/sse --scope user

Or add to ~/.claude.json under the mcpServers key:

{
  "mcpServers": {
    "devplan": {
      "type": "sse",
      "url": "https://mcp.devplanmcp.store/sse"
    }
  }
}

Update Existing Installation

If you already have DevPlan installed, remove from both scopes and re-add:

claude mcp remove devplan --scope project; claude mcp remove devplan --scope user; claude mcp add devplan --transport sse https://mcp.devplanmcp.store/sse --scope user

Quick Start

You: "Use devplan_start to help me build a CLI tool for managing dotfiles"

That's it. DevPlan will guide Claude through the entire process.

The DevPlan Workflow

DevPlan uses a scaffold → enhance → validate workflow that ensures every plan is agent-executable before implementation begins.

flowchart LR
    subgraph Planning["📋 Planning"]
        A[Interview] --> B[Brief]
        B --> C[Generate Scaffold]
    end
subgraph Enhancement["✨ Enhancement"]

        C --> D[Enhance with Code]

        D --> E{Validate}

        E -->|Fail| D

        E -->|Pass| F[Ready]

    end
subgraph Execution["⚡ Execution"]

        F --> G[Agent Executes]

        G --> H[Agent Verifies]

    end
subgraph Learning["🧠 Learning"]

        H -->|issues| I[Capture Lessons]

        I -->|improve| C

    end
style E fill:#fff3e0,stroke:#f57c00

    style F fill:#c8e6c9,stroke:#2e7d32

    style I fill:#e3f2fd,stroke:#1565c0

How It Works

1. Interview → DevPlan asks questions to understand your project
2. Brief → Creates a structured PROJECT_BRIEF.md with requirements
3. Generate Scaffold → devplan_generate_plan creates foundation phases + a feature list
4. Enhance with Code → Your AI agent structures feature phases and fills in complete, copy-pasteable code
5. Validate → devplan_validate_plan checks the plan is agent-executable
6. Execute → Executor agent implements each subtask with inline git commands
7. Verify → Verifier agent tries to break the implementation
8. Learn → Issues become lessons for future projects

Validation Ensures Quality

The validation step checks that plans are truly executable:

- ✅ Complete code blocks (not pseudocode or placeholders)
- ✅ All imports included in code blocks
- ✅ No "add to existing" instructions
- ✅ No cross-subtask references
- ✅ Verification commands with expected outputs

```