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title How to Authenticate When Publishing to the Official MCP Registry
sidebarTitle Authentication
The MCP Registry is currently in preview. Breaking changes or data resets may occur before general availability. If you encounter any issues, please report them on [GitHub](https://github.com/modelcontextprotocol/registry/issues).

You must authenticate before publishing to the official MCP Registry. The MCP Registry supports different authentication methods. Which authentication method you choose determines the namespace of your server's name.

If you choose GitHub-based authentication, your server's name in server.json MUST be of the form io.github.username/* (or io.github.orgname/*). For example, io.github.alice/weather-server.

If you choose domain-based authentication, your server's name in server.json MUST be of the form com.example.*/*, where com.example is the reverse-DNS form of your domain name. For example, io.modelcontextprotocol/everything.

Authentication Name Format Example Name
GitHub-based io.github.username/* or io.github.orgname/* io.github.alice/weather-server
domain-based com.example.*/* io.modelcontextprotocol/everything

GitHub Authentication

GitHub authentication uses an OAuth flow initiated by the mcp-publisher CLI tool.

To perform GitHub authentication, navigate to your server project directory and run:

mcp-publisher login github

You should see output like:

Logging in with github...

To authenticate, please:
1. Go to: https://github.com/login/device
2. Enter code: ABCD-1234
3. Authorize this application
Waiting for authorization...

Visit the link, follow the prompts, and enter the authorization code that was printed in the terminal (e.g., ABCD-1234 in the above output). Once complete, go back to the terminal, and you should see output like:

Successfully authenticated!
✓ Successfully logged in

Personal vs. organization namespaces

GitHub authentication always grants your personal namespace, io.github.<your-username>/*.

To publish under an organization namespace (io.github.<orgname>/*), you must be an Owner of that organization. Ordinary org membership is no longer sufficient: the registry checks your membership role and only grants the org namespace to admins. This prevents anyone who merely belongs to an org from publishing — or overwriting — servers under the org's name.

If you authenticate with a Personal Access Token (for example in CI), the token must let the registry read your organization role. A token that can't will still publish to your personal namespace, but org publishing will be silently unavailable. The exact requirement depends on the token type:

  • Classic PAT: grant the read:org scope.
  • Fine-grained PAT: grant the Organization permissions → Members → Read-only permission (the fine-grained equivalent of read:org). Without it, GitHub returns no organization membership for the token and you'll get your personal namespace only. Note that a fine-grained PAT is bound to a single resource owner, so it can only see the organization it was created for.

Either way the token needs no repository scopes — the registry never reads or writes your code.

DNS Authentication

DNS authentication is a domain-based authentication method that relies on a DNS TXT record.

The TXT record must be placed on the **apex** of your domain (e.g. `example.com`), **not** under a selector like `_mcp-auth.example.com` or `_mcp-registry.example.com`. MCP DNS auth follows SPF-style placement (apex), not DKIM-style (selector). If you put the record under a selector, the registry will not see it and authentication will fail with a generic signature error.

If you rotate keys, also remember to remove the previous TXT record from the apex — a stale record left behind will be tried first and cause verification to fail.

To perform DNS authentication using the mcp-publisher CLI tool, run the following commands in your server project directory to generate a TXT record based on a public/private key pair:

The Ed25519 codepath requires **OpenSSL 3.0 or later**. macOS ships with LibreSSL by default (the system `openssl` binary), which does not implement Ed25519 in `genpkey` and fails with `Algorithm Ed25519 not found`. On macOS, install OpenSSL 3 (`brew install openssl@3`) and invoke it explicitly — for example, replace `openssl` with `/opt/homebrew/opt/openssl@3/bin/openssl` (Apple Silicon) or `/usr/local/opt/openssl@3/bin/openssl` (Intel) in the commands below. The ECDSA P-384 codepath works on LibreSSL. 
MY_DOMAIN="example.com"

# Generate public/private key pair using Ed25519
openssl genpkey -algorithm Ed25519 -out key.pem

# Generate TXT record
PUBLIC_KEY="$(openssl pkey -in key.pem -pubout -outform DER | tail -c 32 | base64)"
echo "${MY_DOMAIN}. IN TXT \"v=MCPv1; k=ed25519; p=${PUBLIC_KEY}\""
MY_DOMAIN="example.com"

# Generate public/private key pair using ECDSA P-384
openssl genpkey -algorithm EC -pkeyopt ec_paramgen_curve:secp384r1 -out key.pem

# Generate TXT record
PUBLIC_KEY="$(openssl ec -in key.pem -text -noout -conv_form compressed | grep -A4 "pub:" | tail -n +2 | tr -d ' :\n' | xxd -r -p | base64)"
echo "${MY_DOMAIN}. IN TXT \"v=MCPv1; k=ecdsap384; p=${PUBLIC_KEY}\""
MY_DOMAIN="example.com"
MY_PROJECT="myproject"
MY_KEYRING="mykeyring"
MY_KEY_NAME="mykey"

# Log in using gcloud CLI (https://cloud.google.com/sdk/docs/install)
gcloud auth login

# Set default project
gcloud config set project "${MY_PROJECT}"

# Create a keyring in your project
gcloud kms keyrings create "${MY_KEYRING}" --location global

# Create an Ed25519 signing key
gcloud kms keys create "${MY_KEY_NAME}" --default-algorithm=ec-sign-ed25519 --purpose=asymmetric-signing --keyring="${MY_KEYRING}" --location=global

# Enable Application Default Credentials (ADC) so the publisher tool can sign
gcloud auth application-default login

# Attempt login to show the public key
mcp-publisher login dns google-kms --domain="${MY_DOMAIN}" --resource="projects/${MY_PROJECT}/locations/global/keyRings/${MY_KEYRING}/cryptoKeys/${MY_KEY_NAME}/cryptoKeyVersions/1"

# Copy the "Expected proof record":
# ${MY_DOMAIN}. IN TXT "v=MCPv1; k=ed25519; p=${PUBLIC_KEY}"
MY_DOMAIN="example.com"
MY_SUBSCRIPTION="subscription name or ID"
MY_RESOURCE_GROUP="MyResourceGroup"
MY_KEY_VAULT="MyKeyVault"
MY_KEY_NAME="MyKey"

# Log in using Azure CLI (https://learn.microsoft.com/en-us/cli/azure/install-azure-cli)
az login

# Set default subscription
az account set --subscription "${MY_SUBSCRIPTION}"

# Create a resource group
az group create --location westus --resource-group "${MY_RESOURCE_GROUP}"

# Create a key vault
az keyvault create --name "${MY_KEY_VAULT}" --location westus --resource-group "${MY_RESOURCE_GROUP}"

# Create an ECDSA P-384 signing key
az keyvault key create --name "${MY_KEY_NAME}" --vault-name "${MY_KEY_VAULT}" --curve P-384

# Attempt login to show the public key
mcp-publisher login dns azure-key-vault --domain="${MY_DOMAIN}" --vault "${MY_KEY_VAULT}" --key "${MY_KEY_NAME}"

# Copy the "Expected proof record":
# ${MY_DOMAIN}. IN TXT "v=MCPv1; k=ecdsap384; p=${PUBLIC_KEY}"

Then add the TXT record using your DNS provider's control panel. It may take several minutes for the TXT record to propagate. After the TXT record has propagated, log in using the mcp-publisher login command:

MY_DOMAIN="example.com"

PRIVATE_KEY="$(openssl pkey -in key.pem -noout -text | grep -A3 "priv:" | tail -n +2 | tr -d ' :\n')"
mcp-publisher login dns --domain "${MY_DOMAIN}" --private-key "${PRIVATE_KEY}"
MY_DOMAIN="example.com"

PRIVATE_KEY="$(openssl ec -in key.pem -noout -text | grep -A4 "priv:" | tail -n +2 | tr -d ' :\n')"
mcp-publisher login dns --domain "${MY_DOMAIN}" --private-key "${PRIVATE_KEY}"
MY_DOMAIN="example.com"
MY_PROJECT="myproject"
MY_KEYRING="mykeyring"
MY_KEY_NAME="mykey"

mcp-publisher login dns google-kms --domain="${MY_DOMAIN}" --resource="projects/${MY_PROJECT}/locations/global/keyRings/${MY_KEYRING}/cryptoKeys/${MY_KEY_NAME}/cryptoKeyVersions/1"
MY_DOMAIN="example.com"
MY_KEY_VAULT="MyKeyVault"
MY_KEY_NAME="MyKey"

mcp-publisher login dns azure-key-vault --domain="${MY_DOMAIN}" --vault "${MY_KEY_VAULT}" --key "${MY_KEY_NAME}"

HTTP Authentication

HTTP authentication is a domain-based authentication method that relies on a /.well-known/mcp-registry-auth file hosted on your domain. For example, https://example.com/.well-known/mcp-registry-auth.

To perform HTTP authentication using the mcp-publisher CLI tool, run the following commands in your server project directory to generate an mcp-registry-auth file based on a public/private key pair:

As with DNS authentication, the Ed25519 codepath requires **OpenSSL 3.0 or later**. macOS's system LibreSSL does not support Ed25519 in `genpkey`. See the note in the [DNS Authentication](#dns-authentication) section for the macOS workaround. 
# Generate public/private key pair using Ed25519
openssl genpkey -algorithm Ed25519 -out key.pem

# Generate mcp-registry-auth file
PUBLIC_KEY="$(openssl pkey -in key.pem -pubout -outform DER | tail -c 32 | base64)"
echo "v=MCPv1; k=ed25519; p=${PUBLIC_KEY}" > mcp-registry-auth
# Generate public/private key pair using ECDSA P-384
openssl genpkey -algorithm EC -pkeyopt ec_paramgen_curve:secp384r1 -out key.pem

# Generate mcp-registry-auth file
PUBLIC_KEY="$(openssl ec -in key.pem -text -noout -conv_form compressed | grep -A4 "pub:" | tail -n +2 | tr -d ' :\n' | xxd -r -p | base64)"
echo "v=MCPv1; k=ecdsap384; p=${PUBLIC_KEY}" > mcp-registry-auth
MY_DOMAIN="example.com"
MY_PROJECT="myproject"
MY_KEYRING="mykeyring"
MY_KEY_NAME="mykey"

# Log in using gcloud CLI (https://cloud.google.com/sdk/docs/install)
gcloud auth login

# Set default project
gcloud config set project "${MY_PROJECT}"

# Create a keyring in your project
gcloud kms keyrings create "${MY_KEYRING}" --location global

# Create an Ed25519 signing key
gcloud kms keys create "${MY_KEY_NAME}" --default-algorithm=ec-sign-ed25519 --purpose=asymmetric-signing --keyring="${MY_KEYRING}" --location=global

# Enable Application Default Credentials (ADC) so the publisher tool can sign
gcloud auth application-default login

# Attempt login to show the public key
mcp-publisher login http google-kms --domain="${MY_DOMAIN}" --resource="projects/${MY_PROJECT}/locations/global/keyRings/${MY_KEYRING}/cryptoKeys/${MY_KEY_NAME}/cryptoKeyVersions/1"

# Copy the "Expected proof record" to `./mcp-registry-auth`:
# v=MCPv1; k=ed25519; p=${PUBLIC_KEY}
MY_DOMAIN="example.com"
MY_SUBSCRIPTION="subscription name or ID"
MY_RESOURCE_GROUP="MyResourceGroup"
MY_KEY_VAULT="MyKeyVault"
MY_KEY_NAME="MyKey"

# Log in using Azure CLI (https://learn.microsoft.com/en-us/cli/azure/install-azure-cli)
az login

# Set default subscription
az account set --subscription "${MY_SUBSCRIPTION}"

# Create a resource group
az group create --location westus --resource-group "${MY_RESOURCE_GROUP}"

# Create a key vault
az keyvault create --name "${MY_KEY_VAULT}" --location westus --resource-group "${MY_RESOURCE_GROUP}"

# Create an ECDSA P-384 signing key
az keyvault key create --name "${MY_KEY_NAME}" --vault-name "${MY_KEY_VAULT}" --curve P-384

# Attempt login to show the public key
mcp-publisher login http azure-key-vault --domain="${MY_DOMAIN}" --vault "${MY_KEY_VAULT}" --key "${MY_KEY_NAME}"

# Copy the "Expected proof record" to `./mcp-registry-auth`:
# v=MCPv1; k=ecdsap384; p=${PUBLIC_KEY}

Then host the mcp-registry-auth file at /.well-known/mcp-registry-auth on your domain. After the file is hosted, log in using the mcp-publisher login command:

MY_DOMAIN="example.com"
PRIVATE_KEY="$(openssl pkey -in key.pem -noout -text | grep -A3 "priv:" | tail -n +2 | tr -d ' :\n')"
mcp-publisher login http --domain "${MY_DOMAIN}" --private-key "${PRIVATE_KEY}"
MY_DOMAIN="example.com"
PRIVATE_KEY="$(openssl ec -in key.pem -noout -text | grep -A4 "priv:" | tail -n +2 | tr -d ' :\n')"
mcp-publisher login http --domain "${MY_DOMAIN}" --private-key "${PRIVATE_KEY}"
MY_DOMAIN="example.com"
MY_PROJECT="myproject"
MY_KEYRING="mykeyring"
MY_KEY_NAME="mykey"

mcp-publisher login http google-kms --domain="${MY_DOMAIN}" --resource="projects/${MY_PROJECT}/locations/global/keyRings/${MY_KEYRING}/cryptoKeys/${MY_KEY_NAME}/cryptoKeyVersions/1"
MY_DOMAIN="example.com"
MY_KEY_VAULT="MyKeyVault"
MY_KEY_NAME="MyKey"

mcp-publisher login http azure-key-vault --domain="${MY_DOMAIN}" --vault "${MY_KEY_VAULT}" --key "${MY_KEY_NAME}"