# Update Prd > Update a ChatPRD document to reflect what was actually built. Use after implementation to capture decisions, trade-offs, and deviations from the original spec. Use when this capability is needed. - Skill: `tomevault-io/update-prd` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/update-prd` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/update-prd/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Product & Planning - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/update-prd --- # Update PRD ## Trigger User finished building a feature and wants to update the PRD to match reality. ## Workflow 1. Find the relevant PRD: - Ask the user which document to update. - Or search using `search_documents`. - Also check the local `prd/` directory. 2. Fetch the current PRD content using `get_document`. 3. Analyze what was actually built: - Review the git diff against the base branch. - Identify the key implementation decisions. 4. Compare the implementation against the original spec and note: - Requirements that were implemented as specified - Deviations and the reasons behind them - Scope that was deferred or cut - New edge cases or considerations discovered during implementation 5. Draft update instructions that: - Mark completed requirements - Document deviations with rationale - Add a "What was actually built" section if significant changes were made - Move deferred items to a "Future work" section 6. Update the document in ChatPRD using `update_document`. 7. Update the local copy in `prd/` to stay in sync. ## Guardrails - Preserve the original PRD structure — add to it, don't rewrite it. - Be honest about deviations — they're documentation, not failures. - Keep the update concise and factual. ## Output - Updated PRD in ChatPRD - Updated local copy in `prd/` - Summary of changes made to the document --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/chatprd) — claim your Tome and manage your conversions.