diff --git a/kfinance/CHANGELOG.md b/kfinance/CHANGELOG.md
index 8b0f41c..763e1bf 100644
--- a/kfinance/CHANGELOG.md
+++ b/kfinance/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Changelog
 
+## v5.1.4
+- Update tools to gracefully handle more errors
+
 ## v5.1.3
 - Bump fastmcp and langchain dependencies
 
diff --git a/kfinance/client/id_resolution.py b/kfinance/client/id_resolution.py
index e346a5e..711e9c7 100644
--- a/kfinance/client/id_resolution.py
+++ b/kfinance/client/id_resolution.py
@@ -9,5 +9,6 @@ async def unified_fetch_id_triples(
     """Resolve one or more identifiers to id triples using the unified (/ids) endpoint."""
 
     resp = await httpx_client.post(url="/ids", json=dict(identifiers=identifiers))
+    resp.raise_for_status()
     resp_json = resp.json()
     return UnifiedIdTripleResponse.model_validate(resp_json)
diff --git a/kfinance/domains/companies/company_tools.py b/kfinance/domains/companies/company_tools.py
index a970214..f5c7c95 100644
--- a/kfinance/domains/companies/company_tools.py
+++ b/kfinance/domains/companies/company_tools.py
@@ -216,6 +216,7 @@ async def fetch_info_from_company_id(
     """Fetch and return company info for one company_id."""
     url = f"/info/{company_id}"
     resp = await httpx_client.get(url=url)
+    resp.raise_for_status()
     return resp.json()
 
 
@@ -316,7 +317,10 @@ async def get_company_summary_or_description_from_identifiers(
                 result = task.result.summary
             else:
                 result = task.result.description
-            results[task.result_key] = result
+            if not result:
+                errors.append(f"No {summary_or_description} found for {task.result_key}.")
+            else:
+                results[task.result_key] = result
 
     if summary_or_description == "summary":
         return GetCompanySummaryFromIdentifiersResp(results=results, errors=errors)
diff --git a/kfinance/domains/cusip_and_isin/cusip_and_isin_tools.py b/kfinance/domains/cusip_and_isin/cusip_and_isin_tools.py
index 3259c6b..183e6d7 100644
--- a/kfinance/domains/cusip_and_isin/cusip_and_isin_tools.py
+++ b/kfinance/domains/cusip_and_isin/cusip_and_isin_tools.py
@@ -126,4 +126,5 @@ async def fetch_cusip_or_isin_from_security_id(
     """Fetch and return the cusip or isin for a security id."""
     url = f"/{cusip_or_isin}/{security_id}"
     resp = await httpx_client.get(url=url)
+    resp.raise_for_status()
     return resp.json()[cusip_or_isin]
diff --git a/kfinance/domains/earnings/earning_tools.py b/kfinance/domains/earnings/earning_tools.py
index cd5e237..9a65fe7 100644
--- a/kfinance/domains/earnings/earning_tools.py
+++ b/kfinance/domains/earnings/earning_tools.py
@@ -246,6 +246,7 @@ async def get_transcript_from_key_dev_id(
     """Fetch raw transcript text for a key_dev_id."""
     url = f"/transcript/{key_dev_id}"
     resp = await httpx_client.get(url=url)
+    resp.raise_for_status()
     transcript_data = resp.json()
 
     # Convert transcript components to raw text format (same as sync version)
diff --git a/kfinance/domains/estimates/estimates_tools.py b/kfinance/domains/estimates/estimates_tools.py
index 156bd4e..8ed2635 100644
--- a/kfinance/domains/estimates/estimates_tools.py
+++ b/kfinance/domains/estimates/estimates_tools.py
@@ -275,6 +275,7 @@ async def fetch_estimates_from_company_id(
         params["num_periods_backward"] = num_periods_backward
 
     resp = await httpx_client.post(url="/estimates/", json=params)
+    resp.raise_for_status()
     return SingleResultResp[Estimates].model_validate(resp.json())
 
 
@@ -324,6 +325,7 @@ async def fetch_consensus_target_price_from_company_id(
 ) -> SingleResultResp[ConsensusTargetPrice]:
     """Fetch consensus target price for one company_id."""
     resp = await httpx_client.get(url=f"/estimates/consensus_target_price/{company_id}")
+    resp.raise_for_status()
     return SingleResultResp[ConsensusTargetPrice].model_validate(resp.json())
 
 
@@ -373,4 +375,5 @@ async def fetch_analyst_recommendations_from_company_id(
 ) -> SingleResultResp[AnalystRecommendations]:
     """Fetch analyst recommendations for one company_id."""
     resp = await httpx_client.get(url=f"/estimates/analyst_recommendations/{company_id}")
+    resp.raise_for_status()
     return SingleResultResp[AnalystRecommendations].model_validate(resp.json())
diff --git a/kfinance/domains/line_items/line_item_tools.py b/kfinance/domains/line_items/line_item_tools.py
index d5257c4..0f26092 100644
--- a/kfinance/domains/line_items/line_item_tools.py
+++ b/kfinance/domains/line_items/line_item_tools.py
@@ -331,5 +331,6 @@ async def fetch_line_item_from_company_ids(
         params["num_periods_back"] = num_periods_back
 
     resp = await httpx_client.post(url="/line_item/", json=params)
+    resp.raise_for_status()
 
     return PostResponse[LineItemResp].model_validate(resp.json())
diff --git a/kfinance/domains/mergers_and_acquisitions/merger_and_acquisition_tools.py b/kfinance/domains/mergers_and_acquisitions/merger_and_acquisition_tools.py
index 00fc974..aeddd21 100644
--- a/kfinance/domains/mergers_and_acquisitions/merger_and_acquisition_tools.py
+++ b/kfinance/domains/mergers_and_acquisitions/merger_and_acquisition_tools.py
@@ -53,7 +53,7 @@ async def _arun(self, identifiers: list[str]) -> GetMergersFromIdentifiersResp:
 
 
 class GetMergerInfoFromTransactionIdArgs(BaseModel):
-    transaction_id: int | None = Field(description="The ID of the transaction.")
+    transaction_id: int = Field(description="The ID of the transaction.")
 
 
 class GetMergerInfoFromTransactionId(KfinanceTool):
@@ -88,7 +88,7 @@ async def _arun(self, transaction_id: int) -> MergerInfo:
 
 
 class GetAdvisorsForCompanyInTransactionFromIdentifierArgs(ToolArgsWithIdentifier):
-    transaction_id: int | None = Field(description="The ID of the merger.")
+    transaction_id: int = Field(description="The ID of the merger.")
 
 
 class GetAdvisorsForCompanyInTransactionFromIdentifierResp(ToolRespWithErrors):
@@ -204,6 +204,7 @@ async def get_advisors_for_company_in_transaction_from_identifier(
     # Fetch advisors for this company in the transaction
     url = f"/merger/info/{transaction_id}/advisors/{company_id}"
     resp = await httpx_client.get(url=url)
+    resp.raise_for_status()
     response_data = resp.json()
 
     advisors_response: list[AdvisorResp] = []
diff --git a/kfinance/domains/prices/price_tools.py b/kfinance/domains/prices/price_tools.py
index fe64c61..aa701ab 100644
--- a/kfinance/domains/prices/price_tools.py
+++ b/kfinance/domains/prices/price_tools.py
@@ -172,6 +172,7 @@ async def fetch_price_history_from_trading_item_id(
 
     url = f"/pricing/{trading_item_id}/{start_date_str}/{end_date_str}/{periodicity.value}/{adjusted_str}"
     resp = await httpx_client.get(url=url)
+    resp.raise_for_status()
     return PriceHistory.model_validate(resp.json())
 
 
diff --git a/kfinance/domains/rounds_of_funding/rounds_of_funding_tools.py b/kfinance/domains/rounds_of_funding/rounds_of_funding_tools.py
index 9770ef1..eae6935 100644
--- a/kfinance/domains/rounds_of_funding/rounds_of_funding_tools.py
+++ b/kfinance/domains/rounds_of_funding/rounds_of_funding_tools.py
@@ -402,11 +402,11 @@ async def get_rounds_of_funding_info_from_transaction_ids(
 
     await batch_execute_async_tasks(tasks=tasks)
 
+    errors: list[str] = []
     round_of_info_responses: dict[int, RoundOfFundingInfo] = dict()
     for task in tasks:
         if task.error:
-            # For now, skip errors in individual round info fetches
-            continue
+            errors.append(f"transaction_id {task.result_key}: {task.error}")
         else:
             round_of_info_responses[task.result_key] = task.result
 
@@ -464,7 +464,7 @@ async def get_rounds_of_funding_info_from_transaction_ids(
 
     return GetRoundsOfFundingInfoFromTransactionIdsResp(
         results=round_of_info_with_advisors,
-        errors=[],  # Individual API failures would be captured in batch execution
+        errors=errors,
     )
 
 
diff --git a/kfinance/domains/rounds_of_funding/tests/test_rounds_of_funding_tools.py b/kfinance/domains/rounds_of_funding/tests/test_rounds_of_funding_tools.py
index 915d93e..f662f61 100644
--- a/kfinance/domains/rounds_of_funding/tests/test_rounds_of_funding_tools.py
+++ b/kfinance/domains/rounds_of_funding/tests/test_rounds_of_funding_tools.py
@@ -485,8 +485,7 @@ async def test_get_rounds_of_funding_info_http_404(
     ) -> None:
         """
         WHEN the server returns a 404 for a non-existent transaction_id
-        THEN the result contains no data for that transaction and no errors are raised
-        note: task errors are purposely ignored in get_rounds_of_funding_info_from_transaction_ids
+        THEN the result contains no data for that transaction and an error is reported
         """
         transaction_id = 999999
 
@@ -498,7 +497,7 @@ async def test_get_rounds_of_funding_info_http_404(
 
         expected_result = GetRoundsOfFundingInfoFromTransactionIdsResp(
             results={},
-            errors=[],
+            errors=[f"transaction_id {transaction_id}: No result found for {transaction_id}."],
         )
 
         result = await get_rounds_of_funding_info_from_transaction_ids(
diff --git a/kfinance/domains/segments/segment_tools.py b/kfinance/domains/segments/segment_tools.py
index 21e24a7..c297a8e 100644
--- a/kfinance/domains/segments/segment_tools.py
+++ b/kfinance/domains/segments/segment_tools.py
@@ -219,5 +219,6 @@ async def fetch_segments_from_company_ids(
 
     url = "/segments/"
     resp = await httpx_client.post(url=url, json=payload)
+    resp.raise_for_status()
 
     return PostResponse[SegmentsResp].model_validate(resp.json())
diff --git a/kfinance/domains/statements/statement_tools.py b/kfinance/domains/statements/statement_tools.py
index d344996..ea2272e 100644
--- a/kfinance/domains/statements/statement_tools.py
+++ b/kfinance/domains/statements/statement_tools.py
@@ -244,5 +244,6 @@ async def fetch_statements_from_company_ids(
 
     url = "/statements/"
     resp = await httpx_client.post(url=url, json=payload)
+    resp.raise_for_status()
 
     return PostResponse[StatementsResp].model_validate(resp.json())
diff --git a/kfinance/integrations/tool_calling/tool_calling_models.py b/kfinance/integrations/tool_calling/tool_calling_models.py
index 35da53b..0a96e65 100644
--- a/kfinance/integrations/tool_calling/tool_calling_models.py
+++ b/kfinance/integrations/tool_calling/tool_calling_models.py
@@ -2,6 +2,7 @@
 from typing import Annotated, Any, Callable, Coroutine, Dict, Literal, Type
 
 from asyncer import syncify
+from httpx import HTTPStatusError
 from langchain_core.tools import BaseTool
 from pydantic import (
     BaseModel,
@@ -16,6 +17,11 @@
 from kfinance.httpx_utils import KfinanceHttpxClient
 
 
+def _sanitize_http_error(e: HTTPStatusError) -> str:
+    """Return the response body from an HTTPStatusError."""
+    return f"{e.response.status_code}: {e.response.text}"
+
+
 class KfinanceTool(BaseTool):
     """KfinanceTool is a langchain base tool with a kfinance Client.
 
@@ -62,7 +68,10 @@ async def arun_without_langchain(self, *args: Any, **kwargs: Any) -> dict:
         args_dict = args_model.model_dump()
         # Only pass params included in the LLM generated kwargs.
         args_dict = {k: v for k, v in args_dict.items() if k in kwargs}
-        result_model = await self._arun(**args_dict)
+        try:
+            result_model = await self._arun(**args_dict)
+        except HTTPStatusError as e:
+            raise Exception(_sanitize_http_error(e)) from None
         return result_model.model_dump(mode="json", exclude_none=True)
 
     async def run_with_endpoint_tracking(self, *args: Any, **kwargs: Any) -> Any:
@@ -75,7 +84,10 @@ async def run_with_endpoint_tracking(self, *args: Any, **kwargs: Any) -> Any:
             args_model = self.args_schema.model_validate(kwargs)
             args_dict = args_model.model_dump()
             args_dict = {k: v for k, v in args_dict.items() if k in kwargs}
-            result_model = await self._arun(**args_dict)
+            try:
+                result_model = await self._arun(**args_dict)
+            except HTTPStatusError as e:
+                raise Exception(_sanitize_http_error(e)) from None
 
             # After completion of tool data fetching and within the endpoint_tracker context manager scope,
             # dequeue the endpoint_tracker_queue
@@ -133,7 +145,8 @@ class ToolArgsWithIdentifiers(BaseModel):
     """
 
     identifiers: list[str] = Field(
-        description="The identifiers, which can be a list of ticker symbols, ISINs, or CUSIPs, or company_ids"
+        min_length=1,
+        description="The identifiers, which can be a list of ticker symbols, ISINs, or CUSIPs, or company_ids",
     )