# Skill 11 Oracle Data Feeds

> Integrates oracle and data feed services including Chainlink and Pyth price feeds, VRF randomness, and Chainlink Automation keepers. Use when consuming on-chain price data, random numbers, or conditional automation.

- **Type:** Skill
- **Install:** `agentstack add skill-vaquarkhan-web3-agent-skills-skill-11-oracle-data-feeds`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [vaquarkhan](https://agentstack.voostack.com/s/vaquarkhan)
- **Installs:** 0
- **Category:** [Developer Tools](https://agentstack.voostack.com/c/developer-tools)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [vaquarkhan](https://github.com/vaquarkhan)
- **Source:** https://github.com/vaquarkhan/web3-agent-skills/tree/main/skills/skill-11-oracle-data-feeds

## Install

```sh
agentstack add skill-vaquarkhan-web3-agent-skills-skill-11-oracle-data-feeds
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Oracle & Data Feeds

## When to Use

- Reading price feeds for DeFi calculations
- Requesting verifiable random numbers (VRF)
- Setting up Chainlink Automation (keepers)
- Validating oracle freshness and deviation thresholds
- Comparing multi-oracle prices for manipulation detection

## Prerequisites

- MCP: `price-feed-server`, `blockchain-rpc-server`
- Skill-08 for oracle manipulation risk assessment

## Workflow

### 1. Chainlink Price Feeds

```solidity
AggregatorV3Interface feed = AggregatorV3Interface(aggregatorAddress);
(, int256 price, , uint256 updatedAt, ) = feed.latestRoundData();
```

**Validation checks:**
- `updatedAt` within heartbeat (varies: 1h ETH/USD, 24h long-tail)
- `price > 0`
- Compare with Pyth/CoinGecko — flag if deviation > 2%

Feed addresses: see `knowledge-base/protocols/` and Chainlink docs per chain.

### 2. Pyth Network

- Pull model: update price feeds in same tx via `getUpdateData()`
- Hermes API for off-chain price reads
- Lower latency than push oracles for L2s

### 3. Chainlink VRF v2.5

1. Subscribe or direct funding
2. Request randomness: `requestRandomWords(keyHash, subId, minConfirmations, callbackGasLimit, numWords)`
3. Fulfill in callback: `fulfillRandomWords(requestId, randomWords)`
4. Never use block variables (`blockhash`, `timestamp`) for randomness

### 4. Chainlink Automation

| Type | Use Case |
|------|----------|
| Time-based | Periodic harvest, rebalance |
| Custom logic | `checkUpkeep()` returns upkeepNeeded |
| Log trigger | React to specific events |

Register upkeep with LINK funding; monitor balance.

### 5. Oracle Security

- Use multiple sources for critical decisions (liquidations, minting)
- Implement staleness checks and circuit breakers
- TWAP for AMM-derived prices (minimum 30-minute window)
- Never use spot DEX price as sole oracle for high-value ops

## References

- `references/chainlink-feeds.md`
- `references/pyth-integration.md`
- `price-feed-server` MCP tools

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [vaquarkhan](https://github.com/vaquarkhan)
- **Source:** [vaquarkhan/web3-agent-skills](https://github.com/vaquarkhan/web3-agent-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-vaquarkhan-web3-agent-skills-skill-11-oracle-data-feeds
- Seller: https://agentstack.voostack.com/s/vaquarkhan
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.