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Custom Connection Data Field Names

Use this when a customer creates a custom/API-key style connected account and tool execution fails with No authentication provided, 401/403 provider errors, or a provider-specific auth error even though the credential itself works directly against the upstream API.

Field names are toolkit-specific

Do not assume every API-key or bearer-token toolkit accepts custom_connection_data.val.api_key. The required field name is toolkit-specific. For example, this shape is incorrect for Crowdin:

{
  "val": {
    "api_key": "<token>"
  }
}

Crowdin expected:

{
  "val": {
    "bearer_token": "<token>"
  }
}

To verify the required field names, inspect toolkit metadata:

curl --location 'https://backend.composio.dev/api/v3.1/toolkits/<toolkit_slug>' \
  --header 'x-api-key: <COMPOSIO_API_KEY>'

Look under:

auth_config_details[].fields.connected_account_initiation.required

If the mismatch continues, share a request ID or log ID with Composio support. If no request ID is available, share how custom_connection_data is being constructed, with secrets removed.

Example response:

Could you share the `custom_connection_data` shape you're sending, with the secret value removed?

The field name is toolkit-specific. For example, some toolkits expect `bearer_token` rather than `api_key`. We can verify the required field from the toolkit metadata and make sure the credential is landing in the right field.

Last verified