# Memory Diff > Surfaces what changed in the user's health since a reference point (date, named event, 'since last X'). Reads workspace memory from med-pdf, health-records, myhealth-pulse, and dated notes; tiers changes by clinical significance. USE FOR: 'what changed', post-visit summaries, longitudinal questions, weekly check-ins. DO NOT USE FOR: news/social (myhealth-pulse), PDFs (med-pdf), chart data (health… - **Type:** Skill - **Install:** `agentstack add skill-realactivity-tula-memory-diff` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [realactivity](https://agentstack.voostack.com/s/realactivity) - **Installs:** 0 - **Category:** [Content & Media](https://agentstack.voostack.com/c/content-and-media) - **Latest version:** 0.1.0 - **License:** Apache-2.0 - **Upstream author:** [realactivity](https://github.com/realactivity) - **Source:** https://github.com/realactivity/tula/tree/main/skills/memory-diff ## Install ```sh agentstack add skill-realactivity-tula-memory-diff ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About # memory-diff ## When to Use ✅ Use when: - User asks "what's changed in my health since " - Post-visit or post-lab summaries - "what's new since my last appointment" - Scheduled weekly or monthly longitudinal check-ins - "Since I started " or "since my referral to " recaps - Another skill needs a "what's new" sub-step (e.g., after `health-records` refresh) ## When NOT to Use ❌ Don't use when: - User wants news or social signal -> use `myhealth-pulse` - User shares a PDF, screenshot, or image -> use `med-pdf` - User asks for raw chart data -> use `health-records` - User wants to draft a clinician message -> use `epic-note` - User asks for medical advice - decline politely; this reads memory, not clinical judgment ## Setup No external tools, no API keys. The skill reads from the local workspace only. Memory sources, in precedence order (full contract in [`references/memory-paths.md`](references/memory-paths.md)): - `~/.openclaw/workspace/.health-records-cache//` - structured FHIR JSON - `~/.openclaw/workspace/.med-pdf-cache//` - extracted JSON from PDFs - `~/.openclaw/workspace/memory/*.md` - dated agent notes - `~/.openclaw/workspace/MEMORY.md` - persistent agent memory - `~/.openclaw/workspace/.myhealth-pulse-cache/.json` - pulse digests ## Workflow 1. **Resolve the reference point.** Default: 7 days ago. Parse named anchors from the prompt: - Calendar phrases: "last week" (7d), "last month" (30d), "last 90 days" - Event anchors: "since I started ", "since my visit" - scan memory for the matching event date - Absolute dates: "since 2026-04-01" - If ambiguous, ask one clarifying question, then proceed. 2. **Enumerate within the window.** For each source above, list files modified or dated within the window. Don't load everything into context - stream-scan headers and key sections. 3. **Classify each change.** Apply the rubric in [`references/clinical-significance.md`](references/clinical-significance.md): - **Tier 1 - signal.** New abnormal lab, med change, new diagnosis, >20% trend change in a tracked marker, new imaging finding, abnormal-to-normal resolution. - **Tier 2 - notable.** Stable abnormality continuing, mild trend, new appointment scheduled, new pulse mentions of relevant topics. - **Tier 3 - noise.** Routine entries, unchanged trends, low-relevance pulse items. Collapsed to a one-line count. 4. **Synthesize.** Tier 1 first (always shown), Tier 2 second (always shown), Tier 3 collapsed (`12 routine entries`). End with one trailing line: `Powered by memory-diff - window: , sources: `. 5. **Empty window.** If nothing in any tier, return one line: `No changes in - last entry: from .` Don't fabricate filler entries. 6. **Cache the rendering.** Write to `~/.openclaw/workspace/.memory-diff-cache/.md`. The next run can diff-of-diff if asked ("what's new since I last asked you this"). ## Examples See [`references/examples.md`](references/examples.md) for since-last-week, since-a-med-change, post-visit, and empty-window outputs. ## Privacy - All reads are workspace-local; nothing outbound, ever. - Output stays in the chat. Don't auto-forward, auto-summarize externally, or include in any outbound notification unless explicitly configured. - Cache stays under `~/.openclaw/workspace/.memory-diff-cache/`. Don't copy out. ## Troubleshooting - **Ambiguous anchor** -> ask one clarifying question, then proceed. Don't guess. - **Conflicting facts across sources** -> surface both with source attribution. Don't silently pick a winner. - **Cache directory missing on first run** -> create it, no error. - **Tuning the tiers** -> in v1, thresholds live in [`references/clinical-significance.md`](references/clinical-significance.md). A forthcoming user dashboard app will let the user tune these through a profile mechanism (same shape as `myhealth-pulse/references/profile-schema.md`). Until then, edit the references file directly. ## Source & license This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [realactivity](https://github.com/realactivity) - **Source:** [realactivity/tula](https://github.com/realactivity/tula) - **License:** Apache-2.0 Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v0.1.0 — what this tool can access: - **Network access:** no - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **0.1.0** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/skill-realactivity-tula-memory-diff - Seller: https://agentstack.voostack.com/s/realactivity - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.