# crypto.defi-chains

DeFi TVL leaderboard across all chains (via DefiLlama, free/keyless): every chain ranked by total value locked, with its native token symbol and chain id. Distinct from crypto.defi (which returns one chain\

Agent View of the PolicyLayer registry record for `crypto.defi-chains`. HTML page: https://policylayer.com/tools/io-github-2s-io-mcp/crypto.defi-chains

## Facts

- Tool: `crypto.defi-chains`
- Server: Mcp (`@2sio/mcp`) — https://policylayer.com/tools/io-github-2s-io-mcp.md
- Install: `npx -y @2sio/mcp`
- Homepage: https://github.com/2s-io/sdk
- 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": "crypto.defi-chains",
    "arguments": {}
  }
}
```

## Why crypto.defi-chains is rated Low

This is a pure data retrieval tool that queries public DeFi metrics (total value locked rankings). It has no side effects, cannot modify data or trigger transactions, and poses minimal risk if misused by an AI agent—at worst, it returns stale or incorrect ranking information. Classification as Read is appropriate.

From the tool's own definition: "Tool description states it 'returns' DeFi TVL leaderboard data 'via DefiLlama' — a data aggregation service. No write, delete, execute, or financial operations are described; it retrieves and ranks existing chain metrics."

Risk signals: Bulk/mass operation — affects multiple targets

## Use case

AI agents call crypto.defi-chains to retrieve information from Mcp 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 Mcp:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "crypto.defi-chains": {}
  }
}
```

## Other tools on Mcp (571)

- `queue.ack` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/queue.ack.md
- `store.blob-delete` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/store.blob-delete.md
- `store.doc-delete` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/store.doc-delete.md
- `store.kv-delete` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/store.kv-delete.md
- `store.vector-delete` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/store.vector-delete.md
- `watchers.cancel` — Destructive — https://policylayer.com/tools/io-github-2s-io-mcp/watchers.cancel.md
- `ai.council` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/ai.council.md
- `ai.screenshot` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/ai.screenshot.md
- `batch.run` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/batch.run.md
- `dev.preflight` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/dev.preflight.md
- `dev.regex-test` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/dev.regex-test.md
- `hash.compute` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/hash.compute.md
- `pubsub.subscribe` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/pubsub.subscribe.md
- `queue.lease` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/queue.lease.md
- `search.crawl` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/search.crawl.md
- `url.render` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/url.render.md
- `watchers.crypto-address-activity` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/watchers.crypto-address-activity.md
- `watchers.earthquake` — Execute — https://policylayer.com/tools/io-github-2s-io-mcp/watchers.earthquake.md
- `predict.crypto-updown` — Financial — https://policylayer.com/tools/io-github-2s-io-mcp/predict.crypto-updown.md
- `predict.wallet` — Financial — https://policylayer.com/tools/io-github-2s-io-mcp/predict.wallet.md
- `watchers.fear-greed` — Financial — https://policylayer.com/tools/io-github-2s-io-mcp/watchers.fear-greed.md
- `watchers.fx-rate` — Financial — https://policylayer.com/tools/io-github-2s-io-mcp/watchers.fx-rate.md
- `agent.knowledge-delta` — Other — https://policylayer.com/tools/io-github-2s-io-mcp/agent.knowledge-delta.md
- `agriculture.drought` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/agriculture.drought.md
- `agriculture.stats` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/agriculture.stats.md
- `ai.chat` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/ai.chat.md
- `ai.classify` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/ai.classify.md
- `ai.describe-image` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/ai.describe-image.md
- `ai.entities` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/ai.entities.md
- `ai.extract` — Read — https://policylayer.com/tools/io-github-2s-io-mcp/ai.extract.md
- …and 541 more: https://policylayer.com/tools/io-github-2s-io-mcp.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-2s-io-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-2s-io-mcp