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pydantic_ai.exceptions

ModelRetry

Bases: Exception

Exception raised when a tool function should be retried.

The agent will return the message to the model and ask it to try calling the function/tool again.

Source code in pydantic_ai_slim/pydantic_ai/exceptions.py 
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class ModelRetry(Exception):
    """Exception raised when a tool function should be retried.

    The agent will return the message to the model and ask it to try calling the function/tool again.
    """

    message: str
    """The message to return to the model."""

    def __init__(self, message: str):
        self.message = message
        super().__init__(message)

message instance-attribute 

message: str = message

The message to return to the model.

UserError

Bases: RuntimeError

Error caused by a usage mistake by the application developer — You!

Source code in pydantic_ai_slim/pydantic_ai/exceptions.py 
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class UserError(RuntimeError):
    """Error caused by a usage mistake by the application developer — You!"""

    message: str
    """Description of the mistake."""

    def __init__(self, message: str):
        self.message = message
        super().__init__(message)

message instance-attribute 

message: str = message

Description of the mistake.

AgentRunError

Bases: RuntimeError

Base class for errors occurring during an agent run.

Source code in pydantic_ai_slim/pydantic_ai/exceptions.py 
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class AgentRunError(RuntimeError):
    """Base class for errors occurring during an agent run."""

    message: str
    """The error message."""

    def __init__(self, message: str):
        self.message = message
        super().__init__(message)

    def __str__(self) -> str:
        return self.message

message instance-attribute 

message: str = message

The error message.

UsageLimitExceeded

Bases: AgentRunError

Error raised when a Model's usage exceeds the specified limits.

Source code in pydantic_ai_slim/pydantic_ai/exceptions.py 
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class UsageLimitExceeded(AgentRunError):
    """Error raised when a Model's usage exceeds the specified limits."""

UnexpectedModelBehavior

Bases: AgentRunError

Error caused by unexpected Model behavior, e.g. an unexpected response code.

Source code in pydantic_ai_slim/pydantic_ai/exceptions.py 
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class UnexpectedModelBehavior(AgentRunError):
    """Error caused by unexpected Model behavior, e.g. an unexpected response code."""

    message: str
    """Description of the unexpected behavior."""
    body: str | None
    """The body of the response, if available."""

    def __init__(self, message: str, body: str | None = None):
        self.message = message
        if body is None:
            self.body: str | None = None
        else:
            try:
                self.body = json.dumps(json.loads(body), indent=2)
            except ValueError:
                self.body = body
        super().__init__(message)

    def __str__(self) -> str:
        if self.body:
            return f'{self.message}, body:\n{self.body}'
        else:
            return self.message

message instance-attribute 

message: str = message

Description of the unexpected behavior.

body instance-attribute 

body: str | None = dumps(loads(body), indent=2)

The body of the response, if available.