What we tested
Probed live on 23 Aug 2026 against rubric v1. 4 of 5 checks passed.
PROBE-VERIFIEDtier 2 of 3
✓Markdown negotiationAccept: text/markdown
—Markdown twin at a predictable URL/page.md
✓llms.txt/llms.txt
✓API catalogRFC 9727
✓MCP server answers/.well-known/mcp/server-card.json → tools/list
What an agent could do here
Read from the page’s own content, with the wording each was drawn from. Inference is kept separate from tested facts — an agent completing the action is tier 3.
UNVERIFIED
register“Try Twelve Data financial APIs for free”
Context
16 sites in the index share the category financial data api, of which 11 are transactional.
How we grade
Three tiers. Every listing shows which one it has reached, and when. The rubric.
tier 1Declared
The site says agents are welcome in its robots.txt. A permission, not a capability.
tier 2Probe-verified
We fetched the site and tested each signal ourselves. Dated, repeatable, re-checked on a schedule.
tier 3Behaviourally verified
An agent completed the action end to end — booked, bought, submitted — and it worked.
Own this site?
1 check did not pass when we last looked: Markdown twin at a predictable URL. Each is a small, specific fix; the rubric says exactly what we look for.
Behavioural verification — an agent completing your booking, purchase or contact flow end to end, with the date published here — opens to a small founding cohort first. Leave an email to be in it.
Related verified sites
Artemis API DocsArtemis provides institutional-grade metrics and programmatic API access for equities, cry
financial data api Benzinga API DocumentationBenzinga API Documentation provides developer resources and REST APIs for financial news,
financial data api Benzinga API DocumentationBenzinga API Documentation provides developer resources for accessing news, market, and co
financial data api Benzinga API DocumentationBenzinga API Documentation provides developer resources for accessing news, market, and co
financial data api Captide APICaptide API provides access to global corporate disclosures and AI-driven insights for fin
financial data api Financial DatasetsFinancial Datasets provides real-time, structured financial data APIs including SEC filing
financial data api Jaarrekening.be API DocsDeveloper documentation for the Jaarrekening.be API providing access to Belgian enterprise
financial data api Manka APIThe Manka API converts bank statement PDFs into structured financial data for credit risk
financial data api Record generated from a live database query. Method: about the index.