> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lexera.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Errors: HTTP Codes and Streamed JSON Payloads

> Lexera returns conventional HTTP codes on the transport layer and streams descriptive JSON error payloads over SSE for tool execution failures.

Lexera uses conventional HTTP status codes for transport-level issues and streams detailed JSON error payloads over the open SSE connection when a tool execution fails. Understanding the difference helps you distinguish between a connection problem and a business-logic rejection, so you can respond with the correct fix.

## Error signatures

| Error signature                 | Description                                                                                                              | Resolution                                                                              |
| ------------------------------- | ------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------- |
| Insufficient AED wallet balance | The workspace wallet lacks the required AED to authorize the jurisdiction pricing tier for `lexera_route_to_specialist`. | Ask a workspace finance administrator to top up the wallet balance.                     |
| Invalid inputs (Zod Error)      | The JSON-RPC arguments failed schema validation, for example a missing required parameter or a type mismatch.            | Review the path and expected fields in the error payload to correct the argument names. |
| HTTP 401 Unauthorized           | The request used an invalid, missing, or expired API key.                                                                | Ensure the Bearer token is correctly formatted in the `Authorization` header.           |

## Streamed error payload example

When a tool execution fails, the error is delivered as a JSON-RPC response over SSE with `isError: true`:

```json theme={null}
{
  "result": {
    "content": [
      {
        "type": "text",
        "text": "{\"error\":\"Insufficient AED wallet balance. This review requires AED 699.00; ask your finance administrator to add a corporate wallet credit.\"}"
      }
    ],
    "isError": true
  },
  "jsonrpc": "2.0",
  "id": 1
}
```

## Detailed error reference

<Accordion title="Insufficient AED wallet balance">
  This error occurs when `lexera_route_to_specialist` attempts to place a temporary hold on the corporate AED wallet and the balance is below the required tier. The streamed payload includes the exact amount needed (for example, AED 699.00 for UAE).

  **Resolution:** Contact a workspace finance administrator to add a corporate wallet credit, then retry the dispatch.
</Accordion>

<Accordion title="Invalid inputs (Zod Error)">
  This error occurs when the JSON-RPC `params.arguments` object does not match the tool's schema. Common causes include missing required fields (such as `document_text` or `target_jurisdiction`), incorrect types, or typos in argument names.

  **Resolution:** Inspect the `path` and `expected` fields in the error payload to identify which argument is invalid, then correct the payload and retry.
</Accordion>

<Accordion title="HTTP 401 Unauthorized">
  This error occurs on the transport layer when the `Authorization` header is missing, malformed, or contains an expired or revoked API key. All authenticated MCP tools require a valid Bearer token.

  **Resolution:** Verify that the header is exactly `Authorization: Bearer lex_...` and that the key is active in the Lexera Developer Dashboard. Regenerate the key if necessary.
</Accordion>