# db_schema

Show database schema/tables.

Agent View of the PolicyLayer registry record for `db_schema`. HTML page: https://policylayer.com/tools/io-github-kivanccakmak-yaver/db-schema

## Facts

- Tool: `db_schema`
- Server: Yaver (`yaver-cli`) — https://policylayer.com/tools/io-github-kivanccakmak-yaver.md
- Install: `npx -y yaver-cli`
- Homepage: https://github.com/kivanccakmak/yaver.io
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 2 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `dsn` | string | no | Connection string |
| `driver` | string | yes | Database: sqlite, postgres, mysql |

Parameters from the server's own tool schema.

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

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "db_schema",
    "arguments": {
      "driver": "<driver>"
    }
  }
}
```

## Why db_schema is rated Low

This tool retrieves metadata about database structure (schema and tables) which is a read-only operation with no side effects. It does not execute queries, modify data, delete anything, or perform financial operations. The low severity reflects minimal blast radius if misused by an AI agent—schema inspection alone cannot alter system state or cause significant harm.

From the tool's own definition: "Tool name 'db_schema' and description 'Show database schema/tables' indicate retrieval and inspection of database structure with no modification, deletion, or execution capabilities."

## Use case

AI agents call db_schema to retrieve information from Yaver 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 Yaver:

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

## Other tools on Yaver (644)

- `acl_remove_peer` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/acl-remove-peer.md
- `cancel_schedule` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/cancel-schedule.md
- `cloud_destroy` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/cloud-destroy.md
- `companion_down` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/companion-down.md
- `data_delete` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/data-delete.md
- `db_push` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/db-push.md
- `db_reset` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/db-reset.md
- `db_restore` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/db-restore.md
- `dns_flush` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/dns-flush.md
- `dns_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/dns-remove.md
- `docker_prune` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/docker-prune.md
- `docker_rm` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/docker-rm.md
- `docker_rmi` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/docker-rmi.md
- `feedback_delete` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/feedback-delete.md
- `forgot_password` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/forgot-password.md
- `git_member_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/git-member-remove.md
- `git_stash` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/git-stash.md
- `guest_delete` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/guest-delete.md
- `guest_revoke` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/guest-revoke.md
- `jobs_cancel` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/jobs-cancel.md
- `machine_onboarding_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/machine-onboarding-remove.md
- `machine_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/machine-remove.md
- `migrate_rollback` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/migrate-rollback.md
- `models_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/models-remove.md
- `monitor_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/monitor-remove.md
- `phone_project_delete` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/phone-project-delete.md
- `proxy_remove` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/proxy-remove.md
- `relay_clear_password` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/relay-clear-password.md
- `release_rollback` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/release-rollback.md
- `remote_destroy` — Destructive — https://policylayer.com/tools/io-github-kivanccakmak-yaver/remote-destroy.md
- …and 614 more: https://policylayer.com/tools/io-github-kivanccakmak-yaver.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`

---

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