Add Yahoo Finance domains to Cowork sandbox network allowlist

[jhormaiker]

Preflight Checklist

• I have searched existing requests and this feature hasn't been requested yet
• This is a single feature request (not multiple features)

Problem Statement

The Cowork sandbox proxy blocks all Yahoo Finance endpoints (finance.yahoo.com, query1.finance.yahoo.com, query2.finance.yahoo.com). This breaks any workflow using the yfinance Python library, which is the standard tool for fetching historical market data for backtesting, ML datasets, and quantitative analysis. Finance and trading are a major use case for Claude, and yfinance is the most common free data source in that space.

Proposed Solution

Add the following domains to the Cowork sandbox allowlist:

• query1.finance.yahoo.com
• query2.finance.yahoo.com
• finance.yahoo.com
• yfapi.net

These are read-only public endpoints — no sensitive user data is ever transmitted to Yahoo Finance. The fix requires only adding these domains to the managed allowlist; no other changes needed.

Workarounds currently required (GitHub Actions relay, manual script execution outside the sandbox) add 40-70 seconds of latency and break the collaborative workflow Cowork is designed for.

Related issues: #30112, #37970, #23818

Alternative Solutions

No response

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

No response

Additional Context

No response