# crow_calibre_list_categories

List available categories in the Calibre library (authors, tags, series, publishers, languages, ratings)

Agent View of the PolicyLayer registry record for `crow_calibre_list_categories`. HTML page: https://policylayer.com/tools/kh0pper-crow/crow-calibre-list-categories

## Facts

- Tool: `crow_calibre_list_categories`
- Server: Crow (`kh0pper/crow`) — https://policylayer.com/tools/kh0pper-crow.md
- Homepage: https://github.com/kh0pper/crow
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

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

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

## Why crow_calibre_list_categories is rated Low

This tool performs a read-only enumeration of library metadata. It retrieves information without creating, modifying, deleting, or executing any operations. The blast radius of misuse is minimal—an attacker gains only visibility into library structure, not access to books, user data, or system control.

From the tool's own definition: "Tool name contains 'list' and description states 'List available categories' — a query operation that retrieves metadata (authors, tags, series, publishers, languages, ratings) from a Calibre library with no modification or side effects."

## Use case

AI agents call crow_calibre_list_categories to retrieve information from Crow without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "crow_calibre_list_categories": {}
  }
}
```

## Other tools on Crow (586)

- `caddy_remove_site` — Destructive — https://policylayer.com/tools/kh0pper-crow/caddy-remove-site.md
- `crow_bookstack_delete` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-bookstack-delete.md
- `crow_campaign_delete` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-campaign-delete.md
- `crow_data_write` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-data-write.md
- `crow_deactivate_server` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-deactivate-server.md
- `crow_delete_bot_schedule` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-bot-schedule.md
- `crow_delete_context_section` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-context-section.md
- `crow_delete_file` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-file.md
- `crow_delete_memory` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-memory.md
- `crow_delete_post` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-post.md
- `crow_delete_setlist` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-delete-setlist.md
- `crow_frigate_set_detect` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-frigate-set-detect.md
- `crow_glasses_undo_last_append` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-glasses-undo-last-append.md
- `crow_identity_revoke` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-identity-revoke.md
- `crow_kb_delete_article` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-kb-delete-article.md
- `crow_linkding_delete` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-linkding-delete.md
- `crow_media_playlist` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-media-playlist.md
- `crow_media_remove_source` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-media-remove-source.md
- `crow_miniflux_remove_feed` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-miniflux-remove-feed.md
- `crow_remove_backend` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-remove-backend.md
- `crow_remove_from_setlist` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-remove-from-setlist.md
- `crow_revoke_access` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-revoke-access.md
- `crow_revoke_instance` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-revoke-instance.md
- `crow_shiori_delete` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-shiori-delete.md
- `crow_tax_purge_return` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-tax-purge-return.md
- `crow_trilium_delete_note` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-trilium-delete-note.md
- `crow_vikunja_delete_task` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-vikunja-delete-task.md
- `crow_wallabag_delete` — Destructive — https://policylayer.com/tools/kh0pper-crow/crow-wallabag-delete.md
- `crowdsec_delete_decision` — Destructive — https://policylayer.com/tools/kh0pper-crow/crowdsec-delete-decision.md
- `fw_defederate` — Destructive — https://policylayer.com/tools/kh0pper-crow/fw-defederate.md
- …and 556 more: https://policylayer.com/tools/kh0pper-crow.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=kh0pper-crow · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/kh0pper-crow