OpenYield Data Services for Claude
The OpenYield connector gives Claude read-only access to OpenYield Data Services: U.S. fixed income reference data, OpenYield marketplace prices, the live U.S. Treasury benchmark curve, TRACE and MSRB prints, and a price, yield and cashflow calculator. Each person signs in with their own Data Services login, and sees exactly the data their account is entitled to, as with the Data API.
It works in Claude on the web, the desktop and mobile apps, Cowork and Claude Code.
Note: The connector requires an OpenYield Data Services account.
Request Access
| Connector URL | Sign-in | Access |
|---|---|---|
https://datamcp.openyld.com/mcp | Your Data Services email and password | Read-only |
Connect
Claude on the web, desktop or mobile: open Customize > Connectors and add a custom connector with the URL above, or find OpenYield Data Services in the directory once it's listed. Then select Connect and sign in.
Team and Enterprise plans: an Owner first adds the connector under Organization settings > Connectors. Each member then connects it and signs in with their own Data Services login.
Claude Code:
claude mcp add --transport http openyield-data https://datamcp.openyld.com/mcp
Then run /mcp and choose the connector to sign in.
Signing in
Connecting opens an OpenYield sign-in page in your browser. It names the app asking for access. Enter your Data Services email and password there; Claude never sees your password. Claude receives a token that works only with this connector.
You stay signed in while you keep using the connector. After 30 days without use, Claude asks you to sign in again. After 5 wrong passwords, an email is locked out for 15 minutes.
Tools
All 17 tools are read-only.
| Tool | What it returns |
|---|---|
| Security by Identifier | Reference data for one security by CUSIP, ISIN or FIGI |
| Securities by Ticker | The ISIN, CUSIP, name and asset class of every active, tradable corporate bond of an issuer, by equity ticker |
| Search Top-of-Book Prices | Securities with a top-of-book bid or ask on the OpenYield marketplace, with prices, yields and quantities |
| Intraday Prices for Security | Today's intraday mid prices for one security |
| Latest Intraday Prices | The latest intraday mid price today for every security in an asset class: government (including bills), corporate, agency or certificate; not municipal |
| Daily Prices for Security | End-of-day mid prices for one security for about the past 3 months |
| Close Prices by Asset | The previous business day's close mid price and yield for every security in an asset class |
| Treasury Benchmark Yield Curve | The live U.S. Treasury benchmark curve: each tenor's security, previous close and current yield |
| Inventory Snapshot | Active marketplace inventory by asset class |
| TRACE Prints | TRACE prints for today or a past date, in sequence order |
| MSRB Prints | MSRB municipal prints for today or a past date, in sequence order |
| Recent Prints for Security | The most recent prints for one security, from any day: 10 by default, up to 100 |
| Prints for Security and Date | Prints for one security traded on one date |
| Print Statistics for Security | Daily print counts by size for one security over about the past 3 months |
| Print Volume by Asset | Securities in an asset class that traded today, with reported and marketplace volume |
| Compute Price/Yield | A bond's price, yields and spread to its benchmark, from a price, a yield or a spread |
| Compute Cashflow | Payment details and future cash flows for a quantity of a bond at a price |
Example questions
- What is the 10-year Treasury yield right now, and how has it moved since yesterday's close?
- Show live quotes on Apple's bonds and say how many of them are quoted.
- Which of Apple's bonds printed on TRACE today, and at what prices?
- What is the yield to worst on that bond at a price of 98.5?
Reading the data
| Topic | Convention |
|---|---|
| Identifiers | CUSIP, ISIN or FIGI, in upper or lower case; tickers likewise. Tickers are matched exactly and aren't exchange-qualified, so unrelated issuers can share one |
| Quantities | Bonds of $1,000 face each: a quantity of 250 is $250,000 face |
| Volumes and cash amounts | Dollars |
| Prices, yields, spreads | Prices per 100 face, yields in percent, spreads in basis points |
| Decimal places | Prices have five decimal places; yields, coupons and curve tenors six; cash amounts, notionals and spreads two. Reported trade prices and quantities keep the precision they were reported with |
| Marketplace prices | Live, intraday and search prices are derived from the OpenYield order book, not evaluated prices |
| Intraday prices | A point every 10 minutes while the bond has a price; a bond with no price at a snapshot has a gap there |
| Floating and step-coupon bonds | No yield is calculated for their quotes |
| Maturity filters | Values under 100 count calendar years from now: in 2026, 5 to 7 means maturing in 2031 through 2033 |
| Close | The previous business day's mid from the OpenYield order book. A bond with no OpenYield close on a day has no price for that day, in close and daily prices alike |
| Print dates and times | The TRACE and MSRB feeds for a date hold the prints reported that day, so they can include late reports of earlier trades, such as the previous evening's after-hours trades; sequence numbers can skip. Prints for Security and Date, Print Statistics and Print Volume by Asset go by the New York trade date instead. as_at is the trade time in Eastern time, with its UTC offset. A yield the feed didn't report is null |
| Print counts and volumes | Each reported leg of a trade is its own print, so counts and volumes include every leg. Capped TRACE sizes count at the cap |
| Parties and side | parties is the reporting party, then the other party: D a dealer, C a customer, A an ATS on the reporting side, or an affiliate or ATS on the other side (is_ats says which). MSRB uses Dealer and Customer. side is the reporting dealer's side, so a dealer's Sell to a customer is a customer buy |
| TRACE | Delayed 4 hours unless your account has the real-time TRACE licence. TRACE caps large sizes: 1000.001 means over $1MM face and 5000.001 over $5MM |
| Treasury shortcuts | CT (coupon) and CB (bill) codes mark on-the-run Treasuries, such as CT10 for the 10-year. B and C suffixes mark the previous two issues. A question about a benchmark, a shortcut or a tenor means these codes. Between a bill's auction and its first quote, the yield curve shows the bill it replaced, under its own code (such as CB06B) |
| Corporate shortcuts | A code such as INTC05 marks the issuer's most recently issued bond with that original term in years, not its remaining term |
| Spread benchmarks | Used only for spreads, such as a spread to the benchmark. Chosen weekly under Bloomberg's rules, so a bond's benchmark can be an older issue: the previous 30-year (CT30B) for long bonds, and for any tenor between an auction and the weekly roll. Spreads need the day's benchmark rate, so they aren't available on weekends, market holidays, or before the rate is published each morning |
Availability and limits
The connector runs from 05:30 to 22:30 ET, the same hours as the Data API. Outside those hours Claude reports it as unavailable; you stay signed in, and it works again from 05:30. Live data, such as marketplace quotes and today's prints, updates between 8am and 5pm ET. On weekends and market holidays there are no quotes or prints for the day; closes, daily prices and print history show the last business day.
Each person can have 3 requests in progress at once. Large results come back in pages, and Claude is told how to fetch the rest.
Results don't include a total count. A page shorter than the limit is the last one.
Two Data Services limits apply to every account, whether through Claude or the Data API:
- Security lookups: each account can look up 5,000 securities a day by identifier, by default. The count resets at midnight ET.
- Print history: without a history subscription, prints, print statistics and recent prints cover the last 7 days (Eastern time, today included). Earlier dates are refused.
Security and privacy
- Read-only: the connector cannot place, change or cancel orders.
- Your password is checked by OpenYield on our own sign-in page and never reaches Claude.
- Tokens: Claude holds a token valid only for this connector. OpenYield stores sign-in tokens only as one-way hashes.
- What we log: your user, the tool used and its parameters (such as the securities you look up), the result status and the time taken. Never passwords or tokens.
- Your conversations: OpenYield receives only the requests Claude makes to the connector, not your conversation. Anthropic processes the data returned to Claude under your Claude plan's terms.
- Claude's answers are its own, not OpenYield data. Check figures against the data the connector returned.
See the OpenYield Privacy Policy.
Disconnecting
Disconnect the connector in Claude's connector settings at any time. OpenYield can also end your Claude sessions or disable your login, which stops data access at once.