# diff_text

utilpeek: Diff two texts: unified line diff, word or character changes. For PDF or Word files use compare_documents. Returns the differences between two texts: similarity ratio, counts and hunks; in line mode a git-compatible unified diff, in word or char mode change records (equal, insert, delete, replace) with exact character offsets into a and b. At most 1,000 hunks and 5,000 change records, then truncated. Parsed in an isolated, resource-limited child process without network; input over its limits is a 422 (not charged). Typically under 0.5 s. Price: USD 0.001. Free: 10 utilpeek calls per IP per UTC day. The submitted text is never logged or stored. Docs: https://tanod.dev/learn/text-diff-api.html

Agent View of the PolicyLayer registry record for `diff_text`. HTML page: https://policylayer.com/tools/dev-tanod-tanod/diff-text

## Facts

- Tool: `diff_text`
- Server: Tanod (`https://tanod.dev/mcp`) — https://policylayer.com/tools/dev-tanod-tanod.md
- Homepage: https://github.com/https://tanod.dev/mcp
- Risk category: Destructive (Critical risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 4 (2 required)
- Recommended policy verdict: Hidden

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `a` | string | yes | The old text (at most 100,000 characters). |
| `b` | string | yes | The new text (at most 100,000 characters). |
| `mode` | string | no | line (default; a unified diff), word or char (at most 20,000 characters per side). |
| `context` | integer | no | Unchanged lines around each hunk (0-10, default 3). |

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": "diff_text",
    "arguments": {
      "a": "<a>",
      "b": "<b>"
    }
  }
}
```

## Why diff_text is rated Critical

An AI agent that decides to call diff_text doesn't hesitate, doesn't double-check, and doesn't stop at one. Whatever it removes from Tanod is gone. There is no undo for destructive operations.

## Use case

AI agents call diff_text to permanently remove resources in Tanod, 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 Tanod:

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

## Other tools on Tanod (307)

- `audit_token_approvals` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/audit-token-approvals.md
- `aurora_forecast` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/aurora-forecast.md
- `image_metadata` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/image-metadata.md
- `pdf_pipeline` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/pdf-pipeline.md
- `pdf_protect` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/pdf-protect.md
- `pdf_remove_pages` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/pdf-remove-pages.md
- `pdf_reorder_pages` — Destructive — https://policylayer.com/tools/dev-tanod-tanod/pdf-reorder-pages.md
- `build_ics_event` — Execute — https://policylayer.com/tools/dev-tanod-tanod/build-ics-event.md
- `build_pptx_deck` — Execute — https://policylayer.com/tools/dev-tanod-tanod/build-pptx-deck.md
- `build_xlsx_workbook` — Execute — https://policylayer.com/tools/dev-tanod-tanod/build-xlsx-workbook.md
- `bulk_agent_index` — Execute — https://policylayer.com/tools/dev-tanod-tanod/bulk-agent-index.md
- `cron_next_runs` — Execute — https://policylayer.com/tools/dev-tanod-tanod/cron-next-runs.md
- `decode_calldata` — Execute — https://policylayer.com/tools/dev-tanod-tanod/decode-calldata.md
- `expand_rrule` — Execute — https://policylayer.com/tools/dev-tanod-tanod/expand-rrule.md
- `html_to_pdf` — Execute — https://policylayer.com/tools/dev-tanod-tanod/html-to-pdf.md
- `image_crop` — Execute — https://policylayer.com/tools/dev-tanod-tanod/image-crop.md
- `parse_ics` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-ics.md
- `parse_phone_number` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-phone-number.md
- `parse_rss_feed` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-rss-feed.md
- `parse_sitemap` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-sitemap.md
- `parse_url` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-url.md
- `parse_user_agent` — Execute — https://policylayer.com/tools/dev-tanod-tanod/parse-user-agent.md
- `render_mermaid` — Execute — https://policylayer.com/tools/dev-tanod-tanod/render-mermaid.md
- `satellite_passes` — Execute — https://policylayer.com/tools/dev-tanod-tanod/satellite-passes.md
- `sec_financials` — Execute — https://policylayer.com/tools/dev-tanod-tanod/sec-financials.md
- `transcribe_audio` — Execute — https://policylayer.com/tools/dev-tanod-tanod/transcribe-audio.md
- `x402_well_known_file` — Execute — https://policylayer.com/tools/dev-tanod-tanod/x402-well-known-file.md
- `compare_stablecoin_transfer_fees` — Financial — https://policylayer.com/tools/dev-tanod-tanod/compare-stablecoin-transfer-fees.md
- `transfer_preflight` — Financial — https://policylayer.com/tools/dev-tanod-tanod/transfer-preflight.md
- `airport_distance` — Read — https://policylayer.com/tools/dev-tanod-tanod/airport-distance.md
- …and 277 more: https://policylayer.com/tools/dev-tanod-tanod.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=dev-tanod-tanod · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/dev-tanod-tanod