One URL turns on 19 hosted MCP servers and 132 tools inside Claude. No account, no API key, no OAuth screen — 92 of those tools answer an anonymous request and always will.
Start with the catalog server. It is the one that answers “is there a skill for this?” and it needs nothing from you.
https://mcp.moltlinestudio.com/catalogAnthropic documents custom connectors on the Pro, Max, Team and Enterprise plans. On Team and Enterprise an Owner adds it once from Admin settings and the whole workspace gets it. Add as many of the 19 URLs as you want — each is a separate connector.
Same URL, one command. --scope user makes it available in every project instead of just this one.
claude mcp add --transport http moltline-catalog --scope user \
https://mcp.moltlinestudio.com/catalog
# then check it came up
claude mcp listA healthy add prints an Added… line, and claude mcp list shows ✓ Connected next to it. Cursor, Codex CLI and anything else that speaks MCP Streamable HTTP take the same URL unchanged — there is no per-client variant.
You should not add a connector on a stranger’s word. Two commands, no credentials, and you can see exactly what it does.
# what is this server and what is in it
curl -s https://mcp.moltlinestudio.com/catalog/.well-known/mcp/server-card.json
# open a session and list the tools
curl -sD- https://mcp.moltlinestudio.com/catalog \
-H 'Content-Type: application/json' \
-H 'Accept: application/json, text/event-stream' \
-d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{
"protocolVersion":"2025-11-25","capabilities":{},
"clientInfo":{"name":"curl","version":"1"}}}'The server card is machine-readable and states the tool counts, the free and premium split, and the protocol versions the server negotiates. Every server on this page publishes one at <url>/.well-known/mcp/server-card.json.
Every one is Streamable HTTP. Every one takes anonymous calls on its free tools. The premium column is what one $19 license unlocks across all of them.
| Server | What it does | Tools | Free | URL |
|---|---|---|---|---|
catalog | Search 138 agent skills and personas by plain-language job | 10 | 6 | https://mcp.moltlinestudio.com/catalog |
codereview | Risk-scan diffs, flag AI-generated-code tells, find secrets | 7 | 5 | https://mcp.moltlinestudio.com/codereview |
govern | Audit MCP configs and skill files for scope and injection risk | 8 | 6 | https://mcp.moltlinestudio.com/govern |
timeops | Deterministic business-day, overlap and recurrence math | 5 | 3 | https://mcp.moltlinestudio.com/timeops |
data | Paste-your-data analytics: profiling, A/B, correlation, growth | 7 | 4 | https://mcp.moltlinestudio.com/data |
humanizer | Find AI-isms with evidence and fingerprint a writing voice | 5 | 3 | https://mcp.moltlinestudio.com/humanizer |
business | 30 finance, bookkeeping, legal-ops and SMB operations products | 8 | 6 | https://mcp.moltlinestudio.com/business |
creator | 20 blogging, brand-voice, copywriting and social products | 8 | 6 | https://mcp.moltlinestudio.com/creator |
educator | 8 curriculum, classroom and exam-prep teaching products | 7 | 5 | https://mcp.moltlinestudio.com/educator |
outbound | 7 outreach, sequencing, deliverability and CRM products | 8 | 6 | https://mcp.moltlinestudio.com/outbound |
personal | 20 inbox, calendar, travel, meals and family-logistics products | 9 | 7 | https://mcp.moltlinestudio.com/personal |
research | 7 research navigation, thesis, note-taking and citation products | 8 | 6 | https://mcp.moltlinestudio.com/research |
skillmd-lint | Lint a SKILL.md for frontmatter, structure, secrets and size | 6 | 6 | https://mcp.moltlinestudio.com/skillmd-lint |
merchant | Processor fees, charge-to-net and invoice totals | 6 | 3 | https://mcp.moltlinestudio.com/merchant |
shipping | Dimensional weight, parcel fit, landed cost, freight class | 6 | 4 | https://mcp.moltlinestudio.com/shipping |
shopify | Product CSV validation, handles, variant matrices, metafields | 6 | 4 | https://mcp.moltlinestudio.com/shopify |
dropship | Margin, lead time, SKU mapping and price-ladder math | 6 | 4 | https://mcp.moltlinestudio.com/dropship |
recall | A portable knowledge-graph memory you pass in and get back | 6 | 4 | https://mcp.moltlinestudio.com/recall |
vision | Image header probing, bbox conversion, resize and color math | 6 | 4 | https://mcp.moltlinestudio.com/vision |
Counts are generated from the license gate in the running code, not written by hand — a tool counts as free when nothing in its body refuses an unlicensed call. Full descriptions on the servers page.
A connector that quietly stops working is worse than one that never worked. A pre-flight run hits all 19 endpoints daily and fails loudly.
Every server completes initialize, is assigned a session, accepts notifications/initialized, and returns its tool list. 19 of 19, or the run fails.
Claude’s web client sends an Origin header that server-to-server tests never send. We send the same header a browser would and assert it is accepted — and that an unrelated origin is still refused.
A free tool is called with no headers, no key and no session history. If it ever starts asking for something, the check goes red before a user finds out.
A premium tool is called without a license and has to refuse politely. That is how we know the free counts on this page are the real ones.
The things people ask before they paste a URL into their assistant.
Anthropic documents custom connectors on the Pro, Max, Team and Enterprise plans. On Team and Enterprise an organization Owner adds it once from Admin settings and it becomes available to the workspace.
No. Leave them empty. There is no account to sign in to, so there is no client ID and no client secret. A connector with no credentials is a supported configuration.
The tool returns a plain sentence saying it needs a license and where to get one. Nothing errors, nothing hangs, and the free tools on that same server keep working.
Not yet. The directory is reviewed by Anthropic and is a separate submission. Adding the URL as a custom connector uses the same MCP mechanism and works today.
Whatever you pass into a tool call, and nothing else. There is no account, so there is nothing to attach a request to. The privacy policy is at moltlinestudio.com/privacy.html.