PlanGate: A Gated Governance Workflow for AI Coding Agents

PlanGate is a governance-first workflow framework for AI programming agents. Its core philosophy is 'admit no code before', using a dual-gate mechanism of C-3 (plan approval) and C-4 (PR review) to ensure AI does not write production code until it gets human approval for plans and test cases. The framework emphasizes approval boundaries, audit capabilities, and Scrum affinity, aiming to balance AI efficiency and human oversight.

Current AI coding tools generally have the problem of excessive autonomy, leading to deviations in demand understanding, lack of auditability, uncontrollable quality, and absence of human oversight. PlanGate uses a structured gated mechanism to fix human judgment points at key nodes, ensuring AI work remains within a controllable range.

PlanGate sets two human approval gates: C-3 and C-4.

Gate	Timing	Judgment Options
C-3	After plan review, before implementation	APPROVE/CONDITIONAL/REJECT
C-4	After AI implementation, on GitHub PR	APPROVE/REQUEST CHANGES

Complete process: Human writes PBI → AI generates plan → C-3 approval → AI implementation (TDD) → Automatic verification (L0/V1-V4) → Create PR → C-4 review → Merge.

1. Plan First: Implementation is only allowed after generating plans, todos, and test cases;
2. Gate Control: C3/C4 cannot be bypassed;
3. Built-in Verification: Multi-layer verification including L0 (lint correction), V1 (acceptance check), etc.;
4. State Persistence: All records are stored in docs/working/TASK-XXXX/ to form an audit trail;
5. Execution Layer Separation: Separation of Workflow/Skill/Agent (v7+);
6. Control OS: Includes components like Intent, Mode (v7.2+).

Typical steps:

1. Create working context (/working-context TASK-XXXX);
2. Edit PBI input (clarify Why/What/acceptance criteria);
3. Generate plan (/ai-dev-workflow plan);
4. C-3 review;
5. Execute implementation (/ai-dev-workflow exec);
6. C-4 review.

Supports multi-tool collaboration:

Tool	Role	Status
Claude Code	Plan generation, execution orchestration	Fully supported
Codex CLI	External review, parallel execution	Fully supported
Gemini CLI	External review	Supported
OpenCode	Implementation agent	Supported
Cursor	Implementation agent	Planned

Governance Value: Provides complete audit trails, clear responsibility division, compliance support, and risk control. Scrum Affinity: PBI aligns with product backlog, plan approval corresponds to Sprint planning meetings, PR review corresponds to code review practices, and state persistence supports Sprint retrospectives.

PlanGate represents the evolution of AI-assisted coding towards governance priority. It does not limit AI capabilities but ensures it maximizes value within the correct boundaries. Suitable for teams balancing AI efficiency and human oversight, its dual-gate architecture, multi-tool support, and extensible DSL allow it to adapt to various scenarios from small projects to enterprise applications.