xfinlink 0.5.1

Free financial data API client — prices, fundamentals, entity resolution for all US equities

xfinlink

Validate and fix financial data merges. Catches silent identifier errors — ticker recycling, bankruptcies, renames, spin-offs — that corrupt research datasets.

Install

pip install xfinlink

That's it. No Docker. No database setup. Works immediately.

Quick start

import pandas as pd
from xfinlink import validate_dataframe

panel = pd.read_csv("my_research_data.csv")

report = validate_dataframe(panel, id_column="ticker", date_column="date")
print(report.summary)
# "1247 rows checked. 828 clean. 419 issues found."

Fix errors automatically

from xfinlink import fix_dataframe

fixed = fix_dataframe(panel, id_column="ticker", date_column="date")
# Adds _entity_id, _canonical_name, _cik, _xfinlink_flag columns

What it catches

• Ticker recycling: GM before 2009 vs GM after 2010 — different companies, different CIKs
• Ticker hijacking: META was an ETF before Facebook claimed it in 2022
• Corporate renames: GHC was WPO (Washington Post) before 2013
• Spin-offs: HPE didn't exist before the HP split in 2015
• Take-privates: DELL went private 2013-2018, different legal entity before and after

Single identifier lookup

from xfinlink import resolve

result = resolve("ticker", "GM", date="2008-06-15")
# Returns: General Motors Corporation (pre-bankruptcy)

result = resolve("ticker", "GM", date="2012-01-15")
# Returns: General Motors Company (post-bankruptcy)

CLI

xfinlink status                # Database stats
xfinlink resolve ticker AAPL   # Look up any identifier
xfinlink validate data.csv --id-column ticker --date-column date
xfinlink fix data.csv --id-column ticker --date-column date
xfinlink serve                 # Local API server
xfinlink mcp                   # AI agent interface

Want WRDS identifiers? (PERMNOs, GVKEYs)

pip install xfinlink[wrds]
xfinlink enrich --wrds

One command, ~5 minutes. Uses your WRDS credentials. Data stays on your machine.

For AI agents

xfinlink mcp

See CLAUDE.md for integration details.