fix: agent goal accuracy (#1583)

Author: shahules786

docs/concepts/metrics/available_metrics/agents.md

@@ -97,6 +97,7 @@ sample = MultiTurnSample(
 )
 
 scorer = ToolCallAccuracy()
+scorer.llm = your_llm
 await scorer.multi_turn_ascore(sample)
 ```
 
@@ -146,7 +147,8 @@ sample = MultiTurnSample(user_input=[
     reference="Table booked at one of the chinese restaurants at 8 pm")
 
 scorer = AgentGoalAccuracyWithReference()
-await metric.multi_turn_ascore(sample)
+scorer.llm = your_llm
+await scorer.multi_turn_ascore(sample)
 
 ```
 

src/ragas/metrics/_goal_accuracy.py

@@ -114,6 +114,9 @@ class AgentGoalAccuracyWithReference(MetricWithLLM, MultiTurnMetric):
     )
     max_retries: int = 1
 
+    async def _ascore(self, row: t.Dict, callbacks: Callbacks) -> float:
+        raise NotImplementedError
+
     async def _multi_turn_ascore(
         self,
         sample: MultiTurnSample,
@@ -153,6 +156,9 @@ class AgentGoalAccuracyWithoutReference(MetricWithLLM, MultiTurnMetric):
     )
     max_retries: int = 1
 
+    async def _ascore(self, row: t.Dict, callbacks: Callbacks) -> float:
+        raise NotImplementedError
+
     async def _multi_turn_ascore(
         self,
         sample: MultiTurnSample,