MCP server
Errors and troubleshooting
What each error means, and what to do when a connection or a tool call does not work.
Errors arrive in two places. Connection errors reject the whole request before any tool runs. Tool errors are ordinary results with isError: true, written for the assistant to read and correct itself from.
Connection errors
These come back with an HTTP status and a JSON-RPC error body.
| HTTP | Code | Message | What it means |
|---|---|---|---|
401 | -32001 | Authentication required. | The request had no Authorization header. |
401 | -32001 | Invalid or expired token. | The credential was revoked, mistyped, or belongs to an account that no longer exists. |
429 | -32029 | Rate limit exceeded. Try again shortly. | More than 120 requests in a minute. See Limits. |
500 | -32603 | Internal server error. | Something failed on our side. Retry, and contact support if it continues. |
A 401 also carries a WWW-Authenticate header naming the server's OAuth metadata. Clients that support OAuth read it and start the sign-in flow on their own, which is why adding the server by URL alone works.
Tool errors
A tool that cannot answer returns a short explanation instead of data:
| Message | What it means |
|---|---|
You do not have access to "acme-store", or your role does not include this data. Call list_projects to see what you can read. | The project is not one you can reach, or your role excludes this part of it. See Access and permissions. |
Not found in "acme-store". | The order, template or conversation id does not exist in that project. |
Rejected: … | An argument was not valid, such as a malformed date. The rest of the message says which. |
Your session is not valid. Reconnect the Oleon connector. | The credential stopped working partway through. Reconnect the client. |
These are answers, not outages. A well-behaved assistant reads them and tries again with a corrected call, such as looking up the right project slug first.
Troubleshooting
My client says it cannot connect or register
Check that the URL is exactly https://api.olee.ai/mcp, with nothing added after /mcp. Remove the connector from your client and add it again. If your browser blocks pop-ups, allow them for your client so the sign-in page can open.
The approval page says it does not recognise the app
The page refuses a request from an app that never registered, or one that asks to be sent back somewhere it did not register. Remove the connector from your client and add it again, so it registers afresh.
The approval page says the link is missing something
The address that opened the page lost part of its request, often because it was copied by hand or opened in a different browser. Start the connection again from your client.
I approved the connection with the wrong account
Open Connections in that account's profile, revoke the approved connection, then sign in as the right account and connect again.
The assistant says it has no access to a project I can open
Ask it to call whoami. If the project is missing, you connected a different account. If it is listed with restricted_by_role: true, your role does not include the data that tool reads. Also check the slug: it is not always the same as the project's display name.
Messages show as [redacted]
That is the default. Ask for the words explicitly, and the assistant can call search_messages or get_conversation with include_message_text. See Privacy and redaction.
An answer seems to be missing records
Look for truncated in the result's _meta. Ask the assistant to narrow the filters, such as a shorter date range or one status, or to raise limit up to 100.
A connector token stopped working
Check Connections in your profile. If the token is no longer listed, it was revoked. Create a new one and update your client.
The assistant does not seem to use Oleon at all
Make sure the connector is switched on for the conversation, then name it in your question, for example "Using Oleon, …". Some clients only offer tools that are enabled in the current chat.