Moltline Studio MCP Tool Pricing: What Solo Devs Pay

Run this first:

curl -i https://moltlinestudio.com/api

The response is an HTTP 402 carrying an x402 challenge. It quotes 19 USDC on Base for one month of the All-Access licence. Your agent reads that price and settles on-chain without a human in the loop. That is the agent path in one command. For a solo developer, though, the more useful question is simpler: should you pay anything at all?

Moltline Studio runs 22 hosted MCP servers that expose 160 tools. One hundred ten of them are free forever, with no account, API key, or signup. The remaining 50 unlock with one $19/month All-Access licence, payable in cryptocurrency through NOWPayments (ETH, USDT, SOL and 300+ coins).

This post prices both paths for one person over a year. It covers what the free tier includes, what the licence unlocks, and how an agent can buy that licence itself over x402.

It also marks where a marketplace catalogue comparison stops being apples to apples. We do not have current third-party pricing in front of us, so you get a checklist for what to verify yourself. The short version: test the free tier against your real workload, then price the licence against it.

How much does Moltline Studio charge for MCP tools?

$ curl -i https://moltlinestudio.com/api
HTTP/2 402

110 of 160 MCP tools cost $0 with no signup. The other 50 sit behind one $19/month All-Access licence. Those are the two numbers this piece prices out for one developer working alone.

That 402 line is the point: the price arrives in the challenge, not on a marketing page. HTTP 402 is a registered status code. The client reads the challenge and settles.

What this comparison can settle: free versus flat licence. What it cannot settle: the competing marketplace's current pricing. We do not have that in front of us. Check the vendor's own page.

Moltline Studio is a one-person studio that builds and runs 22 hosted servers. It is not a catalogue of other vendors' tools, as Where Moltline Fits: Tooling, Not a Builder explains. Do not price it as one.

Test the free path now. Each server has a direct Streamable HTTP endpoint:

https://mcp.moltlinestudio.com/<server>

Paste that into Claude, Claude Code, Cursor, Codex CLI or any MCP client. The free server list is at the full server list.

What do you get free, with no signup?

Free here means free forever, not a trial. No account, no API key, no signup. The 110 free tools are spread across all 22 hosted servers, and they work the moment you paste an endpoint into a client.

Wire one in with a single URL:

https://mcp.moltlinestudio.com/<server>

Replace <server> with any name from the server list, then paste it into Claude, Claude Code, Cursor, Codex CLI or another MCP client. No auth handshake, no key rotation, no onboarding screen. No seat count applies either, and no usage cap is published.

Three extras also cost nothing:

• 138 SKILL.md agent skills, open at GarphenGate/moltline-oss

• A SKILL.md linter for validating your own skill files

• An agent-readiness checker at moltlinestudio.com/agent-check.html, with 21 checks and no signup

The limit on this path is scope, not usage. The other 50 tools stay locked, and no per-tool free trial is published. Confirm your needed tools sit in the free 110 before you consider paying for anything.

For how endpoints and tiers stack together in a real stack, read Practical Stack Composition: Endpoints, Tiers, and Cost.

What does the $19/month All-Access licence unlock?

Unlocking the premium 50 is one purchase, not a menu. A single $19/month All-Access licence covers every premium tool on every server. No per-tool add-on. For a solo developer, no per-seat arithmetic either.

Price and payment are flat: $19/month, paid in cryptocurrency through NOWPayments (ETH, USDT, SOL and 300+ coins). Nothing tiered, nothing metered.

Billing is monthly. The licence renews automatically and you can cancel anytime; the key expires at the end of the paid period. The key is shown on screen and emailed. The $228 yearly figure later in this post is simply $19 x 12, if you keep the licence all year.

Integration is the quiet upside. Premium tools sit on the same 22 servers as the free ones. Unlocking does not mean a second endpoint, a second client config or a second auth flow. Keep the same https://mcp.moltlinestudio.com/<server> URL and set the key once in your MCP client as the X-Moltline-License header.

Three limits, stated plainly:

• The $19 licence is for one developer. Teams have a separate Team plan at $99/month for five seats on one invoice, arranged by email.

• There is no SLA. There is a written support commitment: first response within 24 hours, and confirmed defects fixed within 30 days.

• No uptime percentage is published.

Treat anything not published as absent, not implied.

The server list on /servers.html shows which of the 22 carry the premium 50. For the longer version of how licensing works, read The Moltline All-Access License: A Professional Solution.

What does one solo developer actually pay per year?

The licence covers all 50 premium tools on one payment. Whether you need it depends on which tools you use and for how many months. Whether you or your agent pays does not change the monthly price. Five paths exist.

Rows 2 and 3 are the same licence at the same price: $19, or 19 USDC, per month. Held all year, that is $228. The sum is $19 x 12 = $228.

If you need premium tools for one month only, $19 is the whole cost on either path. Cancel the checkout licence before it renews, or have the agent pay for a single month. For a single job, an agent can pay 2 USDC for a day pass instead.

The x402 figure comes from the live challenge: amount 19000000, which is 19 USDC at six decimals, for one month. Read it from the response yourself before your agent pays.

A marketplace catalogue lists other vendors' tools, so its cost varies by vendor and cannot be priced against one studio's flat licence.

The free tier stays $0 either way. AI agent skills without subscription walks through that cost logic.

Check which of your needed tools sit in the free 110 before paying. The server list at the /servers.html page shows each server and its tools. If your tools are there, your yearly cost is zero.

How does an agent buy the licence with x402?

The $19 checkout is one way to buy the licence. The other is x402, paid by the agent itself.

curl -i https://moltlinestudio.com/api

Hit that endpoint and read what comes back.

It returns a live HTTP 402 challenge. The JSON body lists one accepted payment: scheme exact, network eip155:8453 (Base mainnet), asset set to the USDC contract on Base, and amount 19000000. That is 19 USDC at six decimals. The description names what it buys: one month of the Moltline All-Access licence. The same offer arrives base64-encoded in a payment-required header. No signup, no account, no human in the loop.

Then the flow runs in five steps:

1. Agent calls /api.

2. Reads the 402 challenge: 19 USDC on Base for one month.

3. Sends 19 USDC on Base to the payTo address in the challenge.

4. Retries /api with the transaction hash plus an EIP-191 signature from the paying wallet in the X-PAYMENT header.

5. Gets the licence key back in the response.

Each payment covers one month of All-Access: all 50 premium tools on all 22 servers. It does not buy a single call or a single tool. The challenge response is the authority on asset and amount, so read it before your agent pays.

The trade-off is not price. Both paths cost $19 for the same month. x402 suits an unattended agent with a wallet holding USDC on Base. The NOWPayments checkout at moltlinestudio.com suits a human, and takes ETH, USDT, SOL and 300+ other coins. For one job, the agent can buy a day pass instead: 2 USDC at https://moltlinestudio.com/api/premium/day-pass, through the same five steps, valid until the end of the next UTC day.

For a worked example of calling a tool after settlement, see the server pages. The wider protocol pattern sits in The x402 Pattern: How Agents Pay for Tools Without a Human.

How does this compare to a marketplace catalogue?

A studio and a catalogue answer different questions.

Moltline Studio builds and runs its own 22 servers. A catalogue lists other vendors' servers. Different products, so a flat price comparison misleads. A catalogue fee buys someone else's tool, on someone else's infrastructure.

Compare the cost paths instead:

• Free tier: $0, 110 of 160 tools, no signup.

• All-Access licence: $19/month flat for the other 50.

• x402: the same licence bought by the agent, 19 USDC on Base per month, read from the 402 challenge, or a 2 USDC day pass for a single job.

• Catalogue listing: set per vendor, often per seat or per tool.

The last row is where the comparison stops. We do not have the marketplace's current pricing in front of us, so no honest side-by-side figure can be published. Check that vendor's pricing page yourself.

What it can still settle: for one developer, a flat $19/month only beats per-seat or per-tool models above a few premium tools. Treat those models as hypotheticals, since per-tool rates vary. Evaluating the managed MCP market: metered SaaS vs. flat-rate licensing works through that split.

The free path stays $0 no matter what a catalogue charges. Real zero-cost, not a trial.

Bundles ship through Agensi. Each server carries an MCPize audit result with a public URL you can open yourself. Pick one from the server list and read the grade there instead of trusting a summary.

What should you check before you buy?

1. Open /servers.html and confirm which of your needed tools sit in the free 110 before you pay for anything. The free tier is the baseline; only the remaining 50 require the licence. For evaluation criteria like transport, auth and tool scope, see What to Look for When Evaluating an MCP Server.

2. Know how the $19 licence renews. It is billed monthly and renews automatically. Cancel anytime; the key expires at the end of the paid period. The $228 yearly figure is $19 x 12, if you keep it all year. Consumer-protection guidance on negative-option offers expects renewal terms to be disclosed before billing details are collected (FTC enforcement policy statement), so read them at checkout.

3. Read the live 402 challenge at https://moltlinestudio.com/api before your agent pays. It quotes 19 USDC on Base for one month of All-Access, the same $19 as the checkout. Confirm the amount, network and asset in the response.

4. Check the alternative marketplace's own pricing page yourself. We do not have its current pricing, so no side-by-side figure is printed here. Bring your own numbers.

5. If an audit grade matters, open that server's public MCPize result URL and read the grade at source rather than trusting a summary. Grades run A+ to B+.

None of these checks requires paying first.

Your next step: test the free tier, then price the licence

The checklist above is yours to run. Do it in this order.

First, read the discovery response:

curl -i https://moltlinestudio.com/api

The HTTP 402 challenge comes back live. The amount in that body is the authority on x402 pricing: 19 USDC on Base for one month of All-Access. Trust the live response over any figure printed elsewhere.

Second, paste a free endpoint into your client and confirm the tools work:

https://mcp.moltlinestudio.com/<server>

Pick one server from Moltline Studio and wire it into Claude, Cursor, Codex CLI, or your own client. If the free 110 tools cover the job, your yearly cost is $0. No signup, no key.

If they do not, one $19/month All-Access licence unlocks the other 50 tools. Buy it at the checkout in crypto, or let your agent buy a month over x402. The price is the same either way.

Check the alternative's pricing before you commit. We do not have it in front of us. That check is yours to run.

The server list at /servers.html is where to start.

Conclusion

Pricing for MCP tools gets simple once you separate the free tier from the flat licence.

• 110 of Moltline Studio's 160 tools are free, with no signup or key.

• The $19/month All-Access licence unlocks the other 50 tools, $228 per year for one developer if held all year.

• An agent can buy the same licence over x402: 19 USDC on Base for one month, quoted in the live 402 challenge, or a 2 USDC day pass for a single job.

• Audit grades run A+ to B+, so verify any server's result URL at the source.

Before you buy anything, run the curl against https://moltlinestudio.com/api and wire a free endpoint into your client. If the free tools cover the job, you pay $0. If not, price the licence against how many months you need it. Start with the server list, pick one, and test it today.