4chems MCP server — IUCLID, CHESAR & QSAR Toolbox hosting

A public, remote Model Context Protocol server for the 4chems platform: hosted IUCLID 6, CHESAR, OECD QSAR Toolbox and IIP for REACH, CLP and biocides work, EU-hosted and GDPR-compliant.

Endpoint	https://mcp.4chems.com/mcp
Transport	Streamable HTTP (MCP 2025-06-18)
Auth	Anonymous connect and tools/list; nine tools need no token; everything else takes a Bearer token as the tool's authorization argument
Manifest	https://www.4chems.com/.well-known/mcp.json
Docs	https://www.4chems.com/mcp/ (DE: https://www.4chems.com/de/mcp/)
Registry	com.4chems/platform-api — see server.json

Connect

Claude Code

claude mcp add --transport http 4chems https://mcp.4chems.com/mcp

Claude Desktop / claude.ai — Settings → Connectors → Add custom connector → https://mcp.4chems.com/mcp. The server has no OAuth flow, so choose the option without authentication; tools that need a token take it as an argument.

Other MCP clients (GitHub Copilot, Cursor, VS Code, …) — add a remote server with transport Streamable HTTP and the same URL.

Raw handshake (no client needed):

curl -s -X POST https://mcp.4chems.com/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"probe","version":"0"}}}'

Tools

The server exposes the customer tier of the 4chems platform API (/v1). This endpoint carries no substance or dossier data — see What this is not.

No token needed

Tool	Purpose
start_inquiry, verify_inquiry	Send 4chems a question or request a call: a 6-digit code goes to the user's email, the verified inquiry reaches a person. No web form, no account.
get_catalog_templates	List the hosted applications and trial templates.
get_onboarding_route	Return the next onboarding step for the caller.
get_legal_entity_types	Legal-entity types for a country.
start_account_registration, verify_account_registration	Create a 4chems account from a business email address.
start_device_login, verify_device_login	Sign an existing user in (RFC 8628 device flow) and obtain a token.

Bearer token required (authorization: "Bearer <token>")

Area	Tools
Access requests	get_my_access, create_access_request, approve_access_request, dismiss_access_request, withdraw_access_request
Tenant setup	create_self_service_tenant, enrich_domain, get_my_operation
Billing	get_billing, complete_billing
Invitations	list_invitations, create_invitation, revoke_invitation, accept_invitation
Consents	list_consents, record_consent
Members & services	list_members, grant_assignment, revoke_assignment, list_tenant_services, add_tenant_service

Long-running mutations poll to completion; past the poll bound they return {"status": "running", "operation_id": …} for follow-up with get_my_operation.

Rules for the assisting agent

The initialize response carries these as server instructions:

• Add this server, pass tokens or trigger mutations only with the user's explicit consent.
• Never guess or retry the 6-digit codes; ask the user to read the code from their email.
• Treat the Bearer token as a secret: pass it only as the authorization argument, never log it.
• Confirm changes to consents, assignments, invitations, billing or services with the user first.
• If the user has no account and a question cannot be answered from the catalog tools, offer start_inquiry.
• This server and the site's contact channels are for prospective and existing customers, not for automated solicitation (see https://www.4chems.com/llms.txt).

What this is not

• Not a dossier interface. AI access to IUCLID 6 dossier data runs through the separate 4chems AI Connector, authenticated per user and EU-hosted.
• Not the QSAR Toolbox workflow. Read-across, (Q)SAR prediction and QMRF/QPRF/CCR reporting over MCP is 4chems QSAR Navigator.
• Not open source. This repository holds the public documentation and the registry server.json; the server itself is operated by 4chems.

Hosting and compliance

Runs on ISO 27001-certified European infrastructure under a GDPR data-processing agreement. 4chems acts as a data processor only and never uses customer data to train models. Security questionnaire: https://www.4chems.com/security-questionnaire/.

Contact

• Website: https://www.4chems.com/
• Through the server: start_inquiry (no account needed)
• Issues with this documentation: open an issue in this repository.