[Python] Google ADK Building Agent - Pydantic Validation Error

I am trying to build an agent in Google adk by passing in some JSON formatted input to one agent as input_schema but for some reason the error keeps popping up.

QAAgentPrompt = "Checks the information for accuracy, completeness, and consistency."
ComplianceAgentPrompt = "Reviews the information for adherence to relevant policies, standards, and regulations. Please don't repete anything that's already mentioned by the QAAgent, i.e. <<{QAAgentOutput}>>"
RecommendationAgentPrompt = "Reviews the document for recommendations."


# Sample code assumes all relevant packages have already been imported:


def json_to_memory(file_path):
"""
Reads a JSON file from desktop and stores it in memory as a Python dictionary.
"""
with open(file_path, 'r', encoding='utf-8') as file:
json_data = json.load(file)
return json_data
precedence_mitigation_json = json.dumps(json_to_memory(FilePath))

QAAgent = LlmAgent(
name = "QAAgent",
model = "gemini-2.0-flash",
instructions = QAAgentPrompt,
output_schema = final_output_json,
output_key="QAAgentOutput"
)

ComplianceAgent = LlmAgent(
name = "ComplianceAgent",
model = "gemini-2.0-flash",
input_schema = precedence_mitigation_json,
instructions = ComplianceAgentPrompt,
output_schema = final_output_json,
output_key="ComplianceAgentOutput"
)

RecommendationAgent = LlmAgent(
name = "RecommendationAgent",
model = "gemini-2.0-flash",
instructions = RecommendationAgentPrompt,
output_schema = final_output_json,
output_key="RecommendationAgentOutput"
)

root_agent = SequentialAgent(
name = "RootAgent",
model = "gemini-2.0-flash",
subagents = [QAAgent, ComplianceAgent, RecommendationAgent]
)


Some sample data for precedence_mitigation_json is as belows:

[
{
"States": "California, Nevada, Idaho",
"Counties": "Sierra, Humboldt",
"Category": "Economic Noise",
"Risks": "Potential impacts to local communities.",
"Mitigation": "Implement monitoring and community engagement",
"Precedence": "Relevant federal and state regulations and guidelines cited."
}
]


The type of precedence_mitigation_json is read in as <class 'str'>

The detailed error message is

pydantic_core._pydantic_core.ValidationError: 2 validation errors for LlmAgentoutput_schemaInput should be a subclass of BaseModel [type=is_subclass_of, input_value='\n{\n "passing": "boo...": boolean\n },\n}\n', input_type=str]For further information visit https://errors.pydantic.dev/2.11/v/is_subclass_ofinstructionsExtra inputs are not permitted [type=extra_forbidden, input_value='Checks the information f...eness, and consistency.', input_type=str]For further information visit https://errors.pydantic.dev/2.11/v/extra_forbidden


I tried different ways to reformat the precedence_mitigation_json but none of it works.

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