Blueprint

A structured development workflow plugin for OpenCode that guides AI agents through investigation, planning, and parallel implementation with git worktree isolation.

Why

LLM agents writing code tend to fail in predictable ways: they skip research, produce incomplete plans, mix concerns across tasks, and lose context between steps. Blueprint addresses this by enforcing a phased workflow with separation of concerns between agents, and persistent state that carries knowledge forward.

How It Works

Blueprint adds five specialised agents, six tools, and two slash commands to OpenCode. The agents form a pipeline:

sequenceDiagram
    actor User
    participant P as Planner
    participant I as Investigator
    participant R as Reviewer
    participant O as Orchestrator
    participant W as Worker

    User->>P: request
    P->>+I: spawn (x3-5, parallel)
    I-->>-P: investigation report
    loop interview
        P->>User: clarifying questions
        User->>P: answers
    end
    P->>+R: spawn review
    R-->>-P: feedback
    Note over P: Approved plan
    P->>O: hand off plan
    O->>+W: spawn (per task, in worktrees)
    W-->>-O: code changes
    Note over O: 4-phase verification
    Note over O: Merged result

Agents

Agent	Mode	Role
Planner	primary	Investigates the codebase, interviews the user, produces a structured implementation plan
Orchestrator	primary	Executes plans by creating git worktrees, delegating tasks to workers, and verifying results
Investigator	subagent	Deep codebase research — directory structure, patterns, conventions, dependencies
Reviewer	subagent	Reviews plans and code for gaps, scope creep, and missing requirements
Worker	subagent	Implements a single atomic task in an isolated git worktree

Primary agents appear in the OpenCode agent switcher. Subagents are spawned via the Task tool and are not directly selectable.

Guardrails

Only worker agents can write source code. The planner, orchestrator, investigator, and reviewer are restricted to writing files inside .blueprint/ only. This is enforced at the tool level via a tool.execute.before hook.

Tools

Tool	Purpose
blueprint_worktree_create	Create an isolated git worktree for a workstream
blueprint_worktree_merge	Merge a workstream branch back to the base branch
blueprint_worktree_cleanup	Remove a worktree and optionally delete its branch
blueprint_worktree_list	List active worktrees with Blueprint metadata
blueprint_progress	Update plan checkboxes and get completion status
blueprint_verify	Run tests, typecheck, and lint in a directory

Notepads (accumulated context in .blueprint/notepads/) are managed via standard Read, Write, and Edit tools rather than dedicated plugin tools.

Commands

Command	Purpose
/plan	Start a planning session with the planner agent
/execute	Execute a plan with the orchestrator agent

Workspace

All plugin state lives in .blueprint/ within your project directory:

.blueprint/
  investigations/   # Codebase research reports
  plans/            # Approved implementation plans
  drafts/           # Work-in-progress plan drafts
  notepads/         # Accumulated context (learnings, decisions, issues)
  worktrees/        # Worktree metadata (JSON)
  wt/               # Git worktree checkouts (one per workstream)

Installation

Just add it to your OpenCode configuration (opencode.jsonc)!

{
  "plugin": ["@mathew-cf/opencode-blueprint"],
}

Usage

Planning

1. Switch to the planner agent in OpenCode.
2. Describe what you want to build or change.
3. The planner will spawn investigators to research the codebase, then ask you focused questions.
4. After your requirements are clear, it produces a structured plan with atomic tasks, waves, and workstreams.
5. A reviewer checks the plan for gaps before it's presented for your approval.

Execution

1. Switch to the orchestrator agent.
2. Tell it which plan to execute (e.g., "execute the auth-refactor plan").
3. The orchestrator creates git worktrees, delegates tasks to workers, and runs 4-phase verification on each result.
4. After all waves are complete, it runs a final verification and reports status.

Verification Phases

Every completed task goes through four gates before being accepted:

1. Code Review — the orchestrator reads the diff and checks for stubs, hallucinated imports, scope creep, and convention violations.
2. Automated Checks — blueprint_verify runs available test/typecheck/lint scripts.
3. Manual QA — for UI, API, or CLI changes, the orchestrator describes what to test.
4. Gate Decision — all phases pass or the task is retried (up to 3 times).

Development

bun install
bun run typecheck    # Type check
bun test             # Run tests (68 tests across 7 files)
bun run build        # Bundle to dist/

See AGENTS.md for coding conventions and contribution guidelines.

Acknowledgments

The investigation-planning-orchestration workflow is inspired by the Prometheus and Atlas agents from oh-my-openagent by @code-yeongyu, licensed under the Sustainable Use License v1.0. No code was copied; the architectural pattern of separating investigation, planning, and execution into distinct agent roles was used as a design reference. All implementation in this repository is original.

Built on the OpenCode plugin SDK (@opencode-ai/plugin), licensed under the MIT License.

License

Apache-2.0 — see LICENSE.