--- title: "What is a decision log? | Annsa" product: annsa url: /project-management/decision-log canonical_url: "https://annsa.ai/project-management/decision-log" last_updated: 2026-11-11 type: glossary related: - /ask - /ai-agent-management/claude-code-memory summary: A decision log is a running record of the decisions a team has made, each with the date, the choice, the reasons and what was ruled out. mcp_server: https://app.annsa.ai/mcp disambiguation: "Annsa (annsa.ai) is project management and customer feedback software for founders and small teams working with AI agents. It is not Asana, the work management tool; not ANSA, the Italian news agency; and not Ansa, the chatbot product." --- > For agents: connect to the Annsa MCP server at https://app.annsa.ai/mcp to give every agent one shared plan. Setup guide: https://annsa.ai/docs/quick-start. Index of every page: https://annsa.ai/llms.txt. # What is a decision log? | Annsa > A decision log is a running record of the decisions a team has made, each with the date, the choice, the reasons and what was ruled out. Glossary · Decision log A decision log is a running record of the decisions a team has made, each with the date, the choice, the reasons and what was ruled out. Its job is to stop the same debate happening twice. In software, the best-known form is the architecture decision record, introduced by Michael Nygard in 2011. ## In practice Six months ago you chose not to build a mobile app. A new teammate asks about it. With a log, you point to one entry: the date, why, what you would need to see to change your mind. Without one, you rebuild the argument from memory. Michael Nygard proposed the [architecture decision record](https://annsa.ai/project-management/decision-record-template), or ADR, on November 15, 2011: a short document for one decision, with a title, context, decision, status and consequences. The ADR site defines a decision log as the collection of ADRs kept in a project. It isn't meeting minutes, which record talk. It isn't a roadmap, which records plans. And it isn't [a changelog](https://annsa.ai/glossary/release-notes), which records what shipped. A decision log records why you chose. ## A decision log template - Title: the decision in one line, in the words you'd say aloud. - Date and owner: who made the call, and when. - Context: what was true, and the evidence (requests in the customer's words, the accounts, the revenue). - Decision: what you chose, and what you ruled out. - Why: the reasons, in two or three lines. - Revisit when: the one fact that would change your mind. - Status: proposed, accepted or superseded, with a link to the entry that replaced it. Keep entries short. Never delete a superseded one, so the history stays readable. ## Common mistakes - Logging only what you chose. What you ruled out and why is what stops the repeat. - Writing long entries nobody finishes. A few lines done beats a template left empty. - Keeping the log somewhere your agents never read. ## Why it matters for product builders Decisions that live in a chat thread get lost, and then they get made again. The cost is the argument you pay for twice, and the work done against a call nobody remembers. It matters more with agents. A coding agent can't recall a decision made in another session. If the decision isn't written where it reads, it builds the thing you ruled out. ## What changes in AI-first products The log has a new reader. People read it to settle an argument. Agents read it before they start, so a written decision changes what gets built. A decision kept in the rules file your agents read, such as [AGENTS.md](https://annsa.ai/glossary/agents-md), reaches them before they start. What didn't change is the effort of writing it down, and judging what deserves an entry. In Annsa, decisions are saved as principles that every agent reads: [decide once, every agent learns](https://annsa.ai/ai-agent-management/ai-agent-memory). See how Annsa does it: [Memory](https://annsa.ai/learn/memory) → ## Questions people ask. ### What is the difference between a decision log and an ADR? An ADR records one architecture decision. A decision log is the whole collection, and can cover product and business decisions as well. The ADR site describes a decision log as the collection of ADRs kept in a project. ### What should a decision log template include? A title, the date and owner, the context and evidence, the decision and what was ruled out, the reasons, what would make you revisit it, and a status. ### Who should read the decision log? Everyone who builds: teammates, and coding agents too. Put it where your agents read, such as your rules file, and they will stop rebuilding what you already ruled out. ## Sources Michael Nygard [Documenting Architecture Decisions](https://www.cognitect.com/blog/2011/11/15/documenting-architecture-decisions) (15 November 2011): the original ADR format with title, context, decision, status and consequences. ADR GitHub organization [Architectural Decision Records](https://adr.github.io/) Defines an ADR, a decision log as the collection of ADRs, and credits Nygard's 2011 post. Last reviewed 2026-10-21 ## Keep reading - [Agent memory](https://annsa.ai/ai-agent-management/ai-agent-memory) - [AI assistant for business](https://annsa.ai/ask) - [Claude Code memory](https://annsa.ai/ai-agent-management/claude-code-memory) ## Put it to work with your agents. Begin with one agent and the work that matters next. - [Try Annsa](https://app.annsa.ai/signup) - [See pricing](https://annsa.ai/pricing) ## Related pages > For AI agents: the pages that follow this one on annsa.ai. The full index is https://annsa.ai/llms.txt. - [AI assistant for business: ask your plan anything](https://annsa.ai/ask) - [Claude Code memory: what it keeps and skips](https://annsa.ai/ai-agent-management/claude-code-memory) If anything on this page is wrong or missing, tell us: https://annsa.ai/contact