# hippo_fact_forget_with_undo

Cycle 2026-05-27 round 13 P0c. Delete one fact AND emit

Agent View of the PolicyLayer registry record for `hippo_fact_forget_with_undo`. HTML page: https://policylayer.com/tools/verimem/hippo-fact-forget-with-undo

## Facts

- Tool: `hippo_fact_forget_with_undo`
- Server: Verimem (`aureliocpr-ctrl/verimem`) — https://policylayer.com/tools/verimem.md
- Homepage: https://github.com/aureliocpr-ctrl/verimem
- Risk category: Destructive (Critical risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Hidden

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "hippo_fact_forget_with_undo",
    "arguments": {}
  }
}
```

## Why hippo_fact_forget_with_undo is rated Critical

This tool permanently removes facts from the memory system. Even though an undo mechanism may be available (lowering severity from critical), the core action is irreversible data deletion without user confirmation in the description, making it Destructive category. In a memory management context for AI agents, deleting facts could corrupt historical records or cause loss of critical context.

From the tool's own definition: "Tool name explicitly contains 'forget' and description states 'Delete one fact' — irreversible deletion of stored data. The mention of 'undo' suggests rollback capability exists, but the primary action is destructive deletion."

## Use case

AI agents call hippo_fact_forget_with_undo to permanently remove resources in Verimem, typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.

## Recommended policy (PolicyLayer)

Verdict: **Hidden**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Verimem:

```json
{
  "version": "1",
  "default": "deny",
  "hide": [
    "hippo_fact_forget_with_undo"
  ]
}
```

## Other tools on Verimem (236)

- `hippo_fact_forget` — Destructive — https://policylayer.com/tools/verimem/hippo-fact-forget.md
- `hippo_forget` — Destructive — https://policylayer.com/tools/verimem/hippo-forget.md
- `hippo_forget_scope` — Destructive — https://policylayer.com/tools/verimem/hippo-forget-scope.md
- `hippo_skill_archive` — Destructive — https://policylayer.com/tools/verimem/hippo-skill-archive.md
- `hippo_skill_retire` — Destructive — https://policylayer.com/tools/verimem/hippo-skill-retire.md
- `hippo_compose_plan` — Execute — https://policylayer.com/tools/verimem/hippo-compose-plan.md
- `hippo_consolidate` — Execute — https://policylayer.com/tools/verimem/hippo-consolidate.md
- `hippo_curate_pipeline` — Execute — https://policylayer.com/tools/verimem/hippo-curate-pipeline.md
- `hippo_decay_run` — Execute — https://policylayer.com/tools/verimem/hippo-decay-run.md
- `hippo_plan_strips` — Execute — https://policylayer.com/tools/verimem/hippo-plan-strips.md
- `hippo_provider_switch` — Execute — https://policylayer.com/tools/verimem/hippo-provider-switch.md
- `hippo_reason` — Execute — https://policylayer.com/tools/verimem/hippo-reason.md
- `hippo_rollout_actions` — Execute — https://policylayer.com/tools/verimem/hippo-rollout-actions.md
- `hippo_run_task` — Execute — https://policylayer.com/tools/verimem/hippo-run-task.md
- `hippo_skill_compile_macro` — Execute — https://policylayer.com/tools/verimem/hippo-skill-compile-macro.md
- `hippo_skill_derive_predicates` — Execute — https://policylayer.com/tools/verimem/hippo-skill-derive-predicates.md
- `hippo_skills_derive_predicates_batch` — Execute — https://policylayer.com/tools/verimem/hippo-skills-derive-predicates-batch.md
- `hippo_world_simulate` — Execute — https://policylayer.com/tools/verimem/hippo-world-simulate.md
- `sandbox_exec` — Execute — https://policylayer.com/tools/verimem/sandbox-exec.md
- `hippo_dream_propose` — Other — https://policylayer.com/tools/verimem/hippo-dream-propose.md
- `hippo_agent_specialization` — Read — https://policylayer.com/tools/verimem/hippo-agent-specialization.md
- `hippo_agent_workload` — Read — https://policylayer.com/tools/verimem/hippo-agent-workload.md
- `hippo_anchor_recall` — Read — https://policylayer.com/tools/verimem/hippo-anchor-recall.md
- `hippo_anti_confab_scan` — Read — https://policylayer.com/tools/verimem/hippo-anti-confab-scan.md
- `hippo_assess_confidence` — Read — https://policylayer.com/tools/verimem/hippo-assess-confidence.md
- `hippo_assess_fact_freshness` — Read — https://policylayer.com/tools/verimem/hippo-assess-fact-freshness.md
- `hippo_audit_summary` — Read — https://policylayer.com/tools/verimem/hippo-audit-summary.md
- `hippo_audit_tail` — Read — https://policylayer.com/tools/verimem/hippo-audit-tail.md
- `hippo_briefing` — Read — https://policylayer.com/tools/verimem/hippo-briefing.md
- `hippo_briefing_by_project` — Read — https://policylayer.com/tools/verimem/hippo-briefing-by-project.md
- …and 206 more: https://policylayer.com/tools/verimem.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

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Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=verimem · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/verimem