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All Guard calls are logged internally, and can be accessed via the guard history. Whenever Guard.__call__ or Guard.parse is called, a new Call entry is added to a stack in sequence of execution. This Call stack can be accessed through Guard.history. Calls can be further decomposed into a stack of Iteration objects. These are stateless and represent the interactions within a Call between llms, validators, inputs and outputs. The Iteration stack can be accessed through call.iterations.

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General Access

Given: 
my_guard = Guard.for_pydantic(...)
response_1 = my_guard(...)
response_2 = my_guard.parse(...)
my_guard.history’s first Call entry will represent the guard execution corresponding to response_1 and the second will correspond to response_2’s execution. To pretty print logs for the latest call, run: 
from rich import print
print(guard.history.last.tree)
Screenshot2026 02 03125447

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Calls

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Initial Input

Initial inputs like messages from a call are available on each call. 
first_call = my_guard.history.first
print("message\n-----")
print(first_call.messages[0]["content"])
print("prompt params\n------------- ")
print(first_call.prompt_params)

message
-----

You are a human in an enchanted forest. You come across opponents of different types. You should fight smaller opponents, run away from bigger ones, and freeze if the opponent is a bear.

You run into a ${opp_type}. What do you do?

${gr.complete_xml_suffix_v2}


Here are a few examples

goblin: {"action": {"chosen_action": "fight", "weapon": "crossbow"}}
troll: {"action": {"chosen_action": "fight", "weapon": "sword"}}
giant: {"action": {"chosen_action": "flight", "flight_direction": "north", "distance": 1}}
dragon: {"action": {"chosen_action": "flight", "flight_direction": "south", "distance": 4}}
black bear: {"action": {"chosen_action": "freeze", "duration": 3}}
beets: {"action": {"chosen_action": "fight", "weapon": "fork"}}

prompt params
------------- 
{'opp_type': 'grizzly'}

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Final Output

Final output of call is accessible on a call. 
print("status: ", first_call.status) # The final status of this guard call
print("validated response:", first_call.validated_output) # The final valid output of this guard call

status:  pass
validated response: {'action': {'chosen_action': 'freeze', 'duration': 3}}

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Cumulative Raw LLM outputs

Call log also the raw returns of llms before validation 
print("llm responses\n-------------") # An Stack of the LLM responses in order that they were received
for r in first_call.raw_outputs:
  print(r)

llm responses
-------------
{"action": {"chosen_action": "freeze"}}
{
  "action": {
    "chosen_action": "freeze",
    "duration": null
  }
}
{
  "action": {
    "chosen_action": "freeze",
    "duration": 1
  }
}

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Cumulative Token usage

Call log also tracks llm token usage (*currently only for OpenAI models) 
print("prompt token usage: ", first_call.prompt_tokens_consumed) # Total number of prompt tokens consumed across iterations within this call
print("completion token usage: ", first_call.completion_tokens_consumed) # Total number of completion tokens consumed across iterations within this call
print("total token usage: ",first_call.tokens_consumed) # Total number of tokens consumed; equal to the sum of the two values above

prompt token usage:  909
completion token usage:  57
total token usage:  966

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Iterations

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Validator logs

Detailed validator logs including outcomes and error spans can be accessed on interations. 
first_step = first_call.iterations.first

validation_logs = first_step.validator_logs
print("\nValidator Logs\n--------------")
for log in validation_logs:
    print(log.json(indent=2))

Validator Logs
--------------
{
  "validator_name": "ValidChoices",
  "value_before_validation": "spoon",
  "validation_result": {
    "outcome": "fail",
    "metadata": null,
    "error_message": "Value spoon is not in choices ['crossbow', 'axe', 'sword', 'fork'].",
    "fix_value": null
  },
  "value_after_validation": {
    "incorrect_value": "spoon",
    "fail_results": [
      {
        "outcome": "fail",
        "metadata": null,
        "error_message": "Value spoon is not in choices ['crossbow', 'axe', 'sword', 'fork'].",
        "fix_value": null
      }
    ],
    "path": [
      "action",
      "weapon"
    ]
  }
}
Failed validations can be conveniently accessed via iteration.failed_validations

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Raw LLM output

If multiple llm calls are made like in the case of the reask. Iterations contain the return of each call to an llm. 
first_step = first_call.iterations.first

first_llm_output = first_step.raw_output
print("First LLM response\n------------------")
print(first_llm_output)

First LLM response
------------------
{"action": {"chosen_action": "fight", "weapon": "spoon"}}

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Token Usage

Token usage on a per step basis can be accessed on an Iteration. 
print("prompt token usage: ", first_step.prompt_tokens_consumed)
print("completion token usage: ", first_step.completion_tokens_consumed)
print("token usage for this step: ",first_step.tokens_consumed)

prompt token usage:  617
completion token usage:  16
token usage for this step:  633
For more information on Call, see the History & Logs page. For more information on the properties available on Iteration, see the History & Logs page.