Allow blank text field in bedrock-runtime message content #3525
Description
Describe the bug
With the new citations feature the content of an ai message can be blank.
Regression Issue
- Select this option if this issue appears to be a regression.
Expected Behavior
The second call to the llm with the previous user and ai messages to work
Current Behavior
The second call breaks because is receiving an ai message with just a text string like this " "
Reproduction Steps
import boto3
client = boto3.client("bedrock-runtime", region_name="eu-west-3")
messages = [
{
"role": "user",
"content": [
{
"document": {
"format": "txt",
"name": "My Document",
"source": {
"text": "The grass is green. The sky is blue."
},
"citations": {"enabled": True}
}
},
{"text": "What color is the grass and sky?"}
]
}
]
response = client.converse(
modelId="eu.anthropic.claude-3-7-sonnet-20250219-v1:0",
messages=messages,
inferenceConfig={
"maxTokens": 1000,
"temperature": 0.1
}
)
print(response['output']['message'])
# Append the assistant's response to messages
messages.append(response['output']['message'])
# Add another user message and continue the conversation
messages.append({
"role": "user",
"content": [{"text": "What about the sun?"}]
})
response2 = client.converse(
modelId="eu.anthropic.claude-3-7-sonnet-20250219-v1:0",
messages=messages,
inferenceConfig={
"maxTokens": 1000,
"temperature": 0.1
}
)
print(response2)Possible Solution
Remove blank validation
Additional Information/Context
previous example gives the error:
ValidationException: An error occurred (ValidationException) when calling the Converse operation: The text field in the ContentBlock object at messages.1.content.1 is blank. Add text to the text field, and try again.
because
print(response['output']['message'])
>>>>
{
"role": "assistant",
"content": [
{
"citationsContent": {
"content": [{"text": "The grass is green."}],
"citations": [
{
"title": "My Document",
"sourceContent": [{"text": "The grass is green. "}],
"location": {
"documentChar": {"documentIndex": 0, "start": 0, "end": 20}
},
}
],
}
},
{"text": " "},
{
"citationsContent": {
"content": [{"text": "The sky is blue."}],
"citations": [
{
"title": "My Document",
"sourceContent": [{"text": "The sky is blue."}],
"location": {
"documentChar": {"documentIndex": 0, "start": 20, "end": 36}
},
}
],
}
},
],
}the second message {"text": " "} is causing the problem
SDK version used
1.39.7
Environment details (OS name and version, etc.)
mac OS 15.4.1