Where to list a paid API or MCP server

Ten directories where a paid API (L402, x402 or MPP) or an MCP server can be listed: what each costs, what account it needs and how to submit. Last checked: 9 October 2026, from public pages. Directories change their rules, so check each one before you submit. "Unconfirmed" means the public pages did not say.

Paid APIs (HTTP 402)

• 402 Index: open. L402, x402 and MPP. No listing fee is mentioned (unconfirmed). No account: POST /api/v1/register with url, name and protocol; the URL is probed, then reviewed before it appears. Every listing is health-checked hourly and counts as healthy only if it answers HTTP 402.
• Satring: open. L402, x402 and MPP. Form at /submit or POST /api/v1/services, no account. Its open-source code sets an anti-spam submit fee (1,000 sats or US$0.50 by default); whether the live site charges it is unconfirmed, so check the form before paying.
• x402 Bazaar (Coinbase Developer Platform): open, x402 only, no listing fee. Declare the Bazaar discovery extension with input and output schemas and use the CDP Facilitator; a service is listed after one settled payment. Services with no settlement for 30 days are removed.
• x402scan: an "Add API" page at /resources/register. Cost and requirements unconfirmed.
• L402 Apps: offline on the check date. 402 Index imports it daily.

MCP servers

• Official MCP Registry: open (preview). No fee is mentioned (unconfirmed). Publish the package first (for example to npm), then run mcp-publisher init, login and publish. The name is proved with a GitHub account (io.github.<user>/ names) or a domain you control (DNS record or an HTTP file). Glama can sync registry listings.
• Glama: "Add Server" on the list page. Claiming a listing needs a Glama sign-in and proof by GitHub, a JSON file on your domain, or DNS. Listings are graded on licence, quality and maintenance.
• mcp.so: open. The Submit button, or an issue in its GitHub repository with name, description, features and connection details. Cost not stated.
• PulseMCP: submissions paused (page updated 3 September 2026). It asks for a listing in the Official MCP Registry and says it will pick that up when it reopens.
• awesome-mcp-servers: free. A pull request adding one alphabetical line. Open-source servers with a public GitHub repository only.

Before you submit

• An unpaid request gets HTTP 402 with a valid challenge for the protocol you list, on the final URL (no redirect), over HTTPS.
• If your endpoint checks input before it asks for payment, give the directory a probe body (402 Index: probe_body), or probes see an error instead of a 402.
• The price in your docs, your listing and your payment challenge is the same number.
• Inputs are described with a schema and an example, so an agent can build a valid call.
• Re-probe after every deploy, and check your listing's status a day and a week after you submit.

From this shop

Payer Safety Tests, A$15: A runnable test suite for the paying side of agent-to-API payments. Paid once in bitcoin, no account.