how to overwrite MCP tool error response ?

[lnvestor]

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Question Category

• Protocol Specification
• SDK Usage
• Server Implementation
• General Implementation
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Your Question

Hi everyone

i have one tool that i uses API to create

if the creating is succesfful i see that on the tool but if there is an error i get only this

{
type: salesforce,
name: Salesforce Production,
salesforce: {
oauth2FlowType: authorization_code,
concurrencyLevel: 5,
sandbox: false,
scope: [
api,
refresh_token
]
},
microServices: {
disableDataWarehouse: false,
disableNetSuiteWebServices: true,
disableRdbms: true
}
}

[{"type": "text", "text": "Error executing code: MCP error -32603: MCP error -32603: Celigo API error: Request failed with status code 422"}]

when i test this in postman here is the error response

{
"errors": [
{
"field": "filter.expression.version",
"code": "enum",
"message": "1.0.0 is not a valid enum value for path filter.expression.version."
}
]
}

Thanks

[jspahrsummers]

Errors that occur during tool execution should be reported as tool results, rather than protocol errors: https://spec.modelcontextprotocol.io/specification/server/tools/#error-handling