Technical Planning Templates

This folder contains templates for documenting technical decisions before implementation begins. There are two tiers: full TDD templates for major projects and a lightweight design doc for smaller work.

Which Template Should I Use?

Scope of WorkTemplateTime to Fill Out
New platform, major migration, new system build — work that introduces new architecture, involves multiple stakeholders, or makes decisions that are expensive to reverseFull TDD (Data or AI & Platform)2-4 hours
Feature, enhancement, or non-trivial change to an existing project — a few days to a couple of weeks of work where the system already existsLightweight Design Doc30-60 minutes
Bug fix, config change, copy update — straightforward work with an obvious pathNo template needed — just put the context in the Linear ticket

When in doubt: start with the lightweight doc. If you find yourself writing multiple pages about architecture tradeoffs and needing appendix variants, upgrade to the full TDD.

Templates

TemplateTeamUse When
TDD Data TemplateData PlatformWarehouse migrations, ETL/ELT pipelines, dbt modeling, BI rollouts, CDP/activation, data quality initiatives
TDD AI & Automation TemplateAI, Automation & Platform EngineeringRAG pipelines, agentic systems, MCP servers, workflow automation (n8n, Windmill), API/backend services, frontend features, fine-tuning, AI copilots, LLM integrations
Lightweight Design DocAnyFeatures, enhancements, or non-trivial changes to existing projects on either team

How to Use

Manually

  1. Copy the relevant template into your client repo or project workspace, or point the agent to this folder.
  2. Fill in the header / Document Control section.
  3. Work through the sections — the template guides you through what to write.
  4. Get a review from the team before implementation starts.

With an AI Planning Agent (Cursor, Codex, etc.)

These templates are designed to work in two directions: an AI agent can help you create the plan, and then a different agent session can execute from it.

See agents.md for full instructions on how AI agents should use these templates. The short version:

  1. Open the template + agents.md as context in Cursor (or reference them with @).
  2. Describe what you’re building. The agent will interview you section by section, ask targeted questions, explore the codebase, and draft the doc collaboratively.
  3. Review the draft. The agent flags gaps and open questions. Resolve them with the agent or with teammates.
  4. The completed doc serves both audiences: human reviewers approve it, then the Agent Implementation Context / Handoff Brief section gives a coding agent everything it needs to execute.

Template-Specific Notes

Full TDD Templates

  • Choose the right Appendix variant for the architecture and modeling/strategy sections. The agent can help you pick.
  • Fill the KQA Matrix early — it anchors the entire design to business questions.
  • The Agent Handoff Brief section is near the end. Create one per milestone/workstream.

Lightweight Design Doc

  • Sections 1-3 are the core. Sections 4-8 can be lighter for simpler work.
  • Section 9 (Agent Implementation Context) must be concrete and specific — this is what makes agent execution effective.

Shared Concepts Across the Full TDD Templates

  • KQA Matrix (Key Questions & Answers) — ties architecture decisions back to the business questions the system must answer.
  • Before / After Impact Scorecard — quantifies the expected improvement and defines how you’ll measure it.
  • ADR Index (Architecture Decision Records) — captures trade-offs and rationale so institutional knowledge survives.
  • Appendix Variants — pick-one architecture and modeling/strategy patterns so the template stays relevant across different project types.