How to Monitor Pendle’s PT/YT Price Divergence Signals? On-Chain Arbitrage Opportunities

The sum of PT and YT prices equals the underlying asset, so they are inherently negatively correlated—YT rises when PT falls, and YT falls when PT rises. The core of monitoring price divergence is to check whether the "implied APY" deviates from the "underlying APY." When implied APY is significantly lower than underlying APY, YT is undervalued and PT is overvalued, opening an arbitrage window to buy YT; conversely, it is more advantageous to buy PT to lock in fixed yield. In practice, use open-source scripts or the Pendle AI plugin to monitor spread thresholds.

OKX Exchange
A leading global cryptocurrency platform,suitable for both beginners and experienced traders.
New user benefit: 20% off trading fees upon registration!！

Register Now App Download

1. First Understand What "Divergence" Means – Why Monitor the PT/YT Spread

What to do: Understand the pricing logic of PT and YT in order to identify what constitutes a "divergence."

How to do it: Pendle splits a yield-bearing asset into PT (Principal Token) and YT (Yield Token), and the sum of their prices equals the price of the underlying asset. Implied APY is the market pricing of YT—simply put, it can be understood as "the price of YT."

Scenarios when divergence occurs:

• Implied APY < Underlying APY: YT is undervalued by the market, PT is overvalued; buying YT and waiting for implied APY to revert is profitable.
• Implied APY > Underlying APY: YT is overvalued, PT is undervalued; buying PT to lock in fixed yield is more cost-effective.

What counts as done: You can clearly explain the core criterion for judging divergence—comparing implied APY with underlying APY, rather than simply looking at the dollar prices of PT and YT.

Changes in implied APY are directly linked to PT/YT supply and demand: when many people buy YT, implied APY rises, making YT more expensive and PT cheaper; when many sell YT, implied APY falls, making YT cheaper and PT more expensive.

2. Use Open-Source Scripts to Automatically Monitor Spread Signals

What to do: Use automation scripts from GitHub to continuously monitor the spread between PT implied yield and the underlying yield, triggering alerts when the spread exceeds a set threshold.

How to do it: The community already has ready-made open-source monitoring scripts. The core logic is to pull Pendle API data, calculate the implied yield of PT, and compare it with the underlying asset yield.

Pendle PT Yield Monitor (GitHub project):

1. Clone the repository, use a Python 3.10+ environment, and install the dependency packages.
2. Copy .env.example to .env and fill in email configuration (for notifications).
3. In main.py, configure the target PT market address, chain ID, and expiry timestamp.
4. Set the SPREAD_THRESHOLD value (e.g., 0.015 means a spread above 1.5% triggers an alert).
5. Run python main.py; the script will fetch data, calculate the spread, and send an email when the threshold is exceeded.

Pendle Arbitrage Bot (Node.js version):

1. Clone the repository and run npm install to install dependencies.
2. Configure the Telegram Bot Token and Chat ID (for push notifications).
3. Modify the threshold inside checkArbitrageOpportunities() (e.g., 20%).
4. Run node index.js; the script fetches data every 15 seconds (configurable) and pushes opportunities via Telegram when found.

What counts as done: Successfully running a monitoring script and receiving alert notifications triggered by threshold breaches.

Prerequisites: Node.js or Python environment; Telegram or email capable of receiving alerts.

3. Use the Pendle AI Plugin to Query Market Data (No Coding Required)

What to do: If you prefer not to maintain a monitoring script yourself, use the official Pendle AI plugin to directly query real-time market data.

How to do it: The Pendle AI plugin is an open-source toolkit providing 25 MCP tools that allow AI agents to directly query real-time market data and filter markets by APY.

Installation and usage:

1. Install it via the Claude Code plugin marketplace; run the corresponding command to add the Pendle plugin.
2. Environment requirement: Node.js 20+
3. Query with natural language, for example:

• "Show all PT markets on Arbitrum with implied APY above 8%"
• "Find stablecoin pools on Ethereum where underlying APY is higher than implied APY"

What counts as done: Being able to quickly filter markets with current price-spread divergences through the AI plugin, without manually checking markets one by one.

Market data refreshes every 5 minutes, basically meeting real-time monitoring needs.

OKX Exchange
A leading global cryptocurrency platform,suitable for both beginners and experienced traders.
New user benefit: 20% off trading fees upon registration!！

Register Now App Download

4. Arbitrage Operations After Identifying Divergence Signals

What to do: Execute specific arbitrage trades once a spread signal is detected.

How to do it:

Signal 1: Implied APY lower than underlying APY (YT cheap mode)

• Long yield APY = underlying APY - implied APY (positive value)
• Action: Buy YT on Pendle and hold until maturity to receive future yield; or sell YT after implied APY recovers for a profit.

Signal 2: Implied APY higher than underlying APY (PT cheap mode)

• Action: Buy PT and hold to maturity, locking in the current high implied APY as fixed income.

More advanced operation (yield swing trading): As implied APY fluctuates, switch between PT and YT positions when the market overvalues or undervalues them—essentially "swing trading" the yield. This requires you to independently judge the direction of average future APY—implied APY is only a market consensus, not a prediction.

What counts as done: Being able to execute a buy transaction for PT or YT in the Pendle App, completing an operation based on a price divergence signal.

Common failure reasons:

• Treating "divergence" as "risk-free arbitrage": Implied APY being lower than underlying APY does not guarantee immediate reversion. The spread could disappear because underlying APY falls, not necessarily because YT price rises in your favor.
• Ignoring time decay to maturity: Even if implied APY remains unchanged, as the maturity date approaches, YT's price will naturally decline (less remaining yield to collect) and PT's price will rise. This is time decay, not an arbitrage signal.

Risk warning:

• YT is a high-risk instrument: Buying YT is akin to going long yield. If the decrease in underlying APY outweighs any increase in implied APY, you may incur a loss. YT's price converges to 0 over time and reaches zero at maturity.
• Pendle AMM's implied yield range limits: When implied APY moves outside the AMM's preset range, liquidity may dry up, greatly increasing slippage on exit.
• PT early exit carries discount risk: Before maturity, PT can only be sold on the secondary market; if liquidity is insufficient, you may suffer a substantial discount.

How to confirm you have mastered the monitoring method?

Successfully run the Pendle PT Yield Monitor script, or use the Pendle AI plugin to successfully filter out markets with spreads >1.5%. Then, in the Pendle App, execute a small operation in that market (buy PT or YT) to confirm the entire chain—detect signal → verify data → execute trade → see updated position—works smoothly. It is recommended to start by monitoring 1–2 stablecoin markets (such as USDC pools), where underlying yield fluctuations are relatively smaller and divergence signals are clearer.