Privacy
This page covers the Phở Research Tools connector (https://mcp.pho.chat/mcp and https://mcp.pho.chat/mcp/login) and the free tools on this site. The Phở chat app has its own privacy policy, which also applies to your Phở account if you sign in.
What we receive
Only what is sent in each tool call: the references, DOIs, PubMed IDs or search terms, and, for a PRISMA diagram, the counts. When the tools run inside Claude, ChatGPT or another assistant, the assistant decides what to send. The connector cannot read your chats, files or other connectors.
What we keep, and for how long
- No record of who checked what. We do not store the reference lists or queries sent to us against any person, address or account.
- Lookup cache. To spare the public databases, each lookup we make to Crossref, PubMed or OpenAlex and its public answer is cached for up to 30 days (1 day for Crossref work records). A lookup can contain the reference text. Nothing in the cache identifies who asked.
- Allowance counters. Without an account, usage is counted per day against a salted one-way hash of your IP address (for IPv6, its /64 prefix), never the address itself. With a Phở account, it is counted per month against a salted hash of your account ID. Counters are deleted after 35 days.
- Usage analytics. One event per tool call, sent to PostHog: the tool name, result status, response time, counts (for example, how many references were verified), the assistant's name (for example Claude or ChatGPT) and whether the call was signed in, keyed by the hashed identifier above. Never the references, queries or DOIs. No person profile is created.
- Sign-in tokens. If you use the sign-in address, your assistant sends a token issued by Phở's sign-in provider (Clerk). We check it with Clerk and remember the result for 5 minutes, stored by hash so the cache never holds a usable token.
- Hosting logs. Our host, Vercel, keeps standard request logs, which include IP addresses, for a short period under its own retention rules.
Who else receives your lookups
Crossref, the U.S. National Library of Medicine (PubMed) and OpenAlex receive the lookups needed to answer each call, from our servers, not from your device. Their own privacy policies apply. We do not sell data or use it for advertising, and nothing sent to the tools is used to train AI models.
No side effects
Every tool is a read-only lookup. The connector never writes to your accounts or to any other service.
Contact
Questions or a deletion request: support@pho.chat. Because we do not link stored data to a person, there is usually nothing to delete beyond your Phở account; write to us and we will delete it.
Last updated 6 October 2026.