Connection problems with the MCP Server almost always trace back to one of a handful of causes. Work through this page before escalating.
Most failures come from a single mistake: the Catalog Token was configured as a bearer token or API key instead of being entered in the Sales Layer authorization screen.
The remote server does not accept the Catalog Token as a direct credential. It exchanges it for OAuth credentials during the authorization flow. If your client configuration has an API key field filled in with the Catalog Token, clear it and reconnect using OAuth.
The Catalog Token was entered as an API key or bearer token in the client configuration.
- Remove any API key or bearer token authentication from the client's server configuration.
- Switch the authentication method to OAuth 2.0, using dynamic discovery if the client offers it.
- Reconnect, and enter the Catalog Token only in the Sales Layer authorization screen.
The client is not sending a valid OAuth access token, or the authorization flow never finished.
Disconnect the server in your client, reconnect, and complete the whole OAuth flow without closing the browser window early.
Browser popups are blocked, or the client cannot start the OAuth flow.
Allow popups for the client's domain and try again. In a desktop client, check that it is permitted to open an external browser.
The server was added but authorization did not complete, so no tool list was negotiated.
Disconnect and reconnect, and confirm the browser redirect finishes and returns you to the client. Then ask the assistant to list its available tools again.
Claude Web requires the base URL:
https://mcp.saleslayer.comUsing https://mcp.saleslayer.com/mcp in Claude Web is a known failure. Remove the custom connector, add it again with the base URL, and check that popups and redirects are allowed.
Copilot Studio needs OAuth configured manually in some versions. Use:
| Field | Value |
|---|---|
| Authorization URL | https://mcp.saleslayer.com/oauth/authorize |
| Token URL | https://mcp.saleslayer.com/oauth/token |
| Grant type | Authorization Code with PKCE |
| Code challenge method | S256 |
| Client secret | Leave empty |
Copilot Studio versions without PKCE and S256 support cannot connect to the remote server.
The platform is treating the MCP Server as a REST API and sending a bearer token, which the remote server does not accept.
Three options, in order of preference:
- Use an MCP client node that supports OAuth 2.0 and can complete the authorization flow.
- Call the Catalog REST API directly with the
X-API-KEYheader. For workflows that hit fixed endpoints and do not need an assistant to decide anything, this is the better design. - Use a local MCP deployment, if your organization allows it.
A fully headless deployment that cannot complete an interactive authorization is not a fit for the remote MCP Server. Use the REST API.
The connection is using the Read-only profile.
Disconnect and reconnect with Full access, either by selecting it in the authorization screen or by connecting to https://mcp.saleslayer.com/full/mcp. See Access profiles and permissions.
Confirm that write access is appropriate before switching. Read-only is the safer default for analysis work.
Usually a language mismatch. Plain text search covers the default language only.
Ask the assistant to search a specific language field, such as contains(prod_title_es, 'Abrigo'), or ask it how to search across languages, which runs help_search_multilingual.
Also check that the catalog actually has records matching your status filter. Ask for counts by status first.
The catalog changed outside the current session, and cached data is still being served.
Under Full access, ask the assistant to clear the cache. Under Read-only, start a new session. Writes made through the MCP Server invalidate the cache automatically, so this only affects changes made elsewhere.
For problems with a local Claude Desktop install — the package failing to start, Node version issues, or configuration file locations — see Local development.
The assistant can diagnose some issues itself:
Validate my Sales Layer token and tell me which catalog it points to.
I am getting empty results when searching for products. What should I check?
What version of the MCP server am I connected to?
These run validate_token, help_troubleshoot, and version.
If the problem persists, contact Sales Layer Support with:
- The client or platform, and its version.
- The exact server URL you used.
- The authentication method configured.
- The exact error message, with a screenshot if possible.
- What the authorization screen did, and whether the redirect completed.
- Which access profile you selected.
Never send your full Catalog Token, in a ticket or anywhere else. Support will guide you through validating it securely.