Vertex AI
Use this page to configure a Vertex AI connection for the current v0.6.x Early Access lane.
Scope and release-lane context
Section titled “Scope and release-lane context”This guide covers Google Cloud Vertex AI connection setup for the current v0.6.x Early Access lane.
- Provider: Google Cloud Vertex AI
- Auth path: Service Account JSON key file
- Contract: valid Project ID plus Model ID
- Runtime path: non-streaming for this lane
- mcp synapse remains BYOK/local-only.
- mcp synapse is not a hosted proxy service.
- The product path is non-streaming for this lane.
- The product path uses no hidden retry, backoff, or silent fallback.
Prerequisites
Section titled “Prerequisites”- Active Google Cloud account and project
- Access to Google Cloud Console
- mcp synapse installed and running locally
- Local IDE/client with MCP support
- Billing-enabled project may be required for live API usage, depending on account and plan
Core concepts
Section titled “Core concepts”Working chain:
Google Cloud Project -> Service Account (JSON Auth) -> mcp synapse connection -> IDE MCP server -> prompt response
- Project ID: unique identifier for your target GCP project
- Service Account: machine identity used by local runtime
- Model ID: technical model identifier entered in connection settings
Important:
- Project ID and credentials context must match.
- Model ID should be taken from current Vertex model listings.
Setup steps
Section titled “Setup steps”Enable the Vertex AI API
Section titled “Enable the Vertex AI API”In Google Cloud Console:
- Search for Vertex AI API.
- Open the API page.
- Click Enable.
Create a service account
Section titled “Create a service account”- Go to IAM & Admin -> Service Accounts.
- Click Create Service Account.
- Enter a service account name.
- Continue.
Assign permissions
Section titled “Assign permissions”- Open role selection.
- Assign Vertex AI User (or a broader role only if required by your organization).
- Complete role assignment.
Create and download a JSON key
Section titled “Create and download a JSON key”- Open the created service account.
- Go to Keys.
- Click Add Key -> Create new key.
- Select JSON and create key.
- Save the file in a secure local folder.
Security note:
- Never commit this JSON file to public repositories.
- Treat the file as sensitive secret material.
Project and model validation
Section titled “Project and model validation”You can obtain Project ID from:
- Project selector in Google Cloud Console
project_idfield in the JSON key file- Project Info section in Cloud Dashboard
Validation rule:
- Project ID entered in
mcp synapsemust match the credential and project context exactly.
To establish the model connection:
- Open Vertex AI -> Model Garden.
- Select a model.
- Copy the model technical identifier (Model ID).
- Enter the Model ID in the
mcp synapseconnection form.
Availability note:
- Model availability and access can vary by account, region, and rollout state.
- If you receive not-found or access errors, try another currently available model and re-run preflight.
Connection settings
Section titled “Connection settings”- Location:
- Start with a common default region (for example
us-central1) unless your organization requires a different region.
- Start with a common default region (for example
- Endpoint / Base URL:
- Keep the default unless your environment requires custom routing, private connectivity, or an API gateway.
Guidance:
- Treat region and endpoint choices as environment-specific configuration.
Preflight and IDE integration
Section titled “Preflight and IDE integration”- Run Preflight in mcp synapse.
- If preflight succeeds, click Create Connection.
- Copy the generated MCP config snippet from Connections.
- Paste it into IDE MCP settings and reload the IDE or client.
- Send a simple test prompt.
- Verify request visibility in dashboard or usage views.
Troubleshooting
Section titled “Troubleshooting”Access, permission, or not-found errors
Section titled “Access, permission, or not-found errors”Checks:
- Recheck Project ID
- Recheck credentials path or file
- Recheck the exact Model ID
- Confirm account, region, and model access status
- Re-run preflight
Authentication failures
Section titled “Authentication failures”Checks:
- Confirm the credentials file path
- Confirm valid JSON key file content
- Confirm the correct project context
- Re-run preflight after correcting credentials details
Region or endpoint issues
Section titled “Region or endpoint issues”Checks:
- Revert to the default endpoint if a custom endpoint is unnecessary
- Confirm region and resource alignment
- Re-run preflight after correcting region or endpoint settings
Security and key handling
Section titled “Security and key handling”- Keep credentials local and private
- Do not commit secret files
- Rotate keys if exposure is suspected
- Keep BYOK/local-only explicit.
- Keep not a hosted proxy service explicit.
- Keep non-streaming for this lane explicit.
- No hidden retry, backoff, or silent fallback on the product path.
Minimal checklist
Section titled “Minimal checklist”- Vertex AI API enabled
- Service account created
- Required role assigned
- JSON key generated and stored securely
- Project ID verified
- Model ID selected
- Preflight successful
- Connection created
- IDE MCP config updated
- End-to-end prompt test completed
- Usage visibility verified