fix(bedrock/converse): drop toolSpec.strict for Opus 4.7/4.8 (#31582)

litellm/litellm_core_utils/prompt_templates/factory.py

@@ -5035,15 +5035,18 @@ def _bedrock_tools_pt(tools: List, model: Optional[str] = None) -> List[BedrockT
     ]
     """
     from litellm.llms.bedrock.common_utils import (
-        get_bedrock_base_model,
+        bedrock_converse_supports_strict_tools,
         normalize_json_schema_custom_types_to_object,
     )
     from litellm.litellm_core_utils.prompt_templates.common_utils import unpack_defs
 
     _valid_json_schema_root_types = frozenset(("array", "boolean", "integer", "null", "number", "object", "string"))
     # Only Claude on Bedrock honours strict tool schemas; other families
-    # (Nova, Llama, GPT-OSS) reject the strict field outright.
-    supports_strict_tools = bool(model and get_bedrock_base_model(model).startswith("anthropic"))
+    # (Nova, Llama, GPT-OSS) reject the strict field outright. Opus 4.7/4.8
+    # also reject `strict` on Bedrock Converse (see #31582) — their validator
+    # maps toolSpec to the native Anthropic tool shape, which has no strict
+    # field, even though Anthropic's native API accepts it as a top-level key.
+    supports_strict_tools = bool(model and bedrock_converse_supports_strict_tools(model))
     tool_block_list: List[BedrockToolBlock] = []
     for tool_idx, tool in enumerate(tools):
         # Check if tool is already a BedrockToolBlock (e.g., systemTool for Nova grounding)

litellm/llms/bedrock/common_utils.py

@@ -4,9 +4,11 @@
 Common utilities used across bedrock chat/embedding/image generation
 """
 
+import contextlib
 import functools
 import json
 import os
+import re
 from typing import (
     TYPE_CHECKING,
     Any,
@@ -718,6 +720,51 @@ def is_claude_4_5_on_bedrock(model: str) -> bool:
     return any(pattern in model_lower for pattern in claude_4_5_patterns)
 
 
+_BEDROCK_MODEL_VERSION_SUFFIX_RE = re.compile(r"-v\d+(?::\d+)?$")
+
+
+def bedrock_converse_supports_strict_tools(model: str) -> bool:
+    """
+    Whether ``toolSpec.strict`` can be forwarded to Bedrock Converse for ``model``.
+
+    Non-Anthropic Bedrock families (Nova, Llama, GPT-OSS) reject the field
+    outright. Anthropic models forward it unless their entry in
+    ``model_prices_and_context_window.json`` sets
+    ``bedrock_converse_supports_strict_tools: false`` — Bedrock routes those
+    (Opus 4.7/4.8, see #31582) through a stricter validator that rejects the
+    ``strict`` key on ``toolSpec`` even though Anthropic's native API accepts
+    it as a top-level tool field.
+    """
+    base = get_bedrock_base_model(model)
+    if not base.startswith("anthropic"):
+        return False
+    flag = _get_bedrock_converse_strict_tools_flag(base)
+    return flag if flag is not None else True
+
+
+def _get_bedrock_converse_strict_tools_flag(base_model: str) -> Optional[bool]:
+    candidates = dict.fromkeys((base_model, _BEDROCK_MODEL_VERSION_SUFFIX_RE.sub("", base_model)))
+    for candidate in candidates:
+        with contextlib.suppress(Exception):
+            model_info = get_cached_model_info()(
+                model=candidate,
+                custom_llm_provider="bedrock",
+            )
+
+            flag = model_info.get("bedrock_converse_supports_strict_tools")
+            if isinstance(flag, bool):
+                return flag
+
+            model_cost_key = model_info.get("key")
+            if isinstance(model_cost_key, str):
+                local_flag = (
+                    _get_local_model_cost_map().get(model_cost_key, {}).get("bedrock_converse_supports_strict_tools")
+                )
+                if isinstance(local_flag, bool):
+                    return local_flag
+    return None
+
+
 def normalize_bedrock_opus_output_config_effort(model: str, output_config: Any) -> None:
     """
     Normalize Anthropic ``output_config.effort`` values for Bedrock Opus ids.

litellm/model_prices_and_context_window_backup.json

@@ -1154,6 +1154,7 @@
         "bedrock_output_config_effort_ceiling": "max"
     },
     "anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1203,6 +1204,7 @@
         "supports_output_config": true
     },
     "global.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1237,6 +1239,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "us.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1271,6 +1274,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "eu.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1305,6 +1309,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "au.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1471,6 +1476,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1505,6 +1511,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "global.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1539,6 +1546,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "us.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1573,6 +1581,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "eu.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1607,6 +1616,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "au.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1641,6 +1651,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "jp.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_read_input_token_cost": 5.5e-07,
         "input_cost_per_token": 5.5e-06,

litellm/types/utils.py

@@ -152,6 +152,7 @@ class ProviderSpecificModelInfo(TypedDict, total=False):
     supports_output_config: Optional[bool]
     supports_image_size: Optional[bool]
     bedrock_output_config_effort_ceiling: Optional[Literal["low", "medium", "high", "max", "xhigh"]]
+    bedrock_converse_supports_strict_tools: Optional[bool]
 
 
 class SearchContextCostPerQuery(TypedDict, total=False):

litellm/utils.py

@@ -5458,6 +5458,7 @@ def _get_model_info_helper(
                 supports_xhigh_reasoning_effort=_model_info.get("supports_xhigh_reasoning_effort", None),
                 supports_max_reasoning_effort=_model_info.get("supports_max_reasoning_effort", None),
                 bedrock_output_config_effort_ceiling=_model_info.get("bedrock_output_config_effort_ceiling", None),
+                bedrock_converse_supports_strict_tools=_model_info.get("bedrock_converse_supports_strict_tools", None),
                 supports_computer_use=_model_info.get("supports_computer_use", None),
                 search_context_cost_per_query=_model_info.get("search_context_cost_per_query", None),
                 web_search_billing_unit=_model_info.get("web_search_billing_unit", None),

model_prices_and_context_window.json

@@ -1154,6 +1154,7 @@
         "bedrock_output_config_effort_ceiling": "max"
     },
     "anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1203,6 +1204,7 @@
         "supports_output_config": true
     },
     "global.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1237,6 +1239,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "us.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1271,6 +1274,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "eu.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1305,6 +1309,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "au.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1471,6 +1476,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1505,6 +1511,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "global.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.25e-06,
         "cache_creation_input_token_cost_above_1hr": 1e-05,
@@ -1539,6 +1546,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "us.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1573,6 +1581,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "eu.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1607,6 +1616,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "au.anthropic.claude-opus-4-8": {
+        "bedrock_converse_supports_strict_tools": false,
         "supports_adaptive_thinking": true,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_creation_input_token_cost_above_1hr": 1.1e-05,
@@ -1641,6 +1651,7 @@
         "bedrock_output_config_effort_ceiling": "xhigh"
     },
     "jp.anthropic.claude-opus-4-7": {
+        "bedrock_converse_supports_strict_tools": false,
         "cache_creation_input_token_cost": 6.875e-06,
         "cache_read_input_token_cost": 5.5e-07,
         "input_cost_per_token": 5.5e-06,

tests/test_litellm/litellm_core_utils/prompt_templates/test_bedrock_converse_strict_tools_opus_47_48.py

@@ -0,0 +1,107 @@
+"""Regression tests for Bedrock Converse ``toolSpec.strict`` forwarding.
+
+Bedrock Converse routes Claude Opus 4.7/4.8 through an Anthropic-compatible
+validator that rejects ``toolSpec.strict`` even though Anthropic's native API
+accepts ``strict`` as a top-level tool field for the same models. See
+BerriAI/litellm#31582.
+"""
+
+import pytest
+
+from litellm.litellm_core_utils.prompt_templates.factory import _bedrock_tools_pt
+from litellm.llms.bedrock.common_utils import bedrock_converse_supports_strict_tools
+
+
+_STRICT_TOOL = [
+    {
+        "type": "function",
+        "function": {
+            "name": "get_weather",
+            "strict": True,
+            "description": "Get the weather for a city",
+            "parameters": {
+                "type": "object",
+                "properties": {
+                    "city": {"type": "string"},
+                    "unit": {"type": "string", "enum": ["celsius"]},
+                },
+                "required": ["city", "unit"],
+                "additionalProperties": False,
+            },
+        },
+    }
+]
+
+
+@pytest.mark.parametrize(
+    "model_id",
+    [
+        "bedrock/us.anthropic.claude-opus-4-7",
+        "bedrock/us.anthropic.claude-opus-4-8",
+        "anthropic.claude-opus-4-7",
+        "anthropic.claude-opus-4-8",
+        "anthropic.claude-opus-4-7-v1:0",
+        "bedrock/eu.anthropic.claude-opus-4-8-v1:0",
+        "bedrock/global.anthropic.claude-opus-4-7",
+    ],
+)
+def test_bedrock_tools_pt_strict_dropped_for_opus_47_48(model_id: str) -> None:
+    """Opus 4.7/4.8 on Bedrock Converse reject toolSpec.strict — must be dropped."""
+    result = _bedrock_tools_pt(_STRICT_TOOL, model=model_id)
+    assert "strict" not in result[0]["toolSpec"], f"strict leaked into toolSpec for {model_id}: {result[0]['toolSpec']}"
+
+
+@pytest.mark.parametrize(
+    "model_id",
+    [
+        "anthropic.claude-sonnet-4-5-20250929-v1:0",
+        "bedrock/us.anthropic.claude-sonnet-4-6",
+        "bedrock/us.anthropic.claude-opus-4-6",
+        "bedrock/us.anthropic.claude-opus-4-5",
+    ],
+)
+def test_bedrock_tools_pt_strict_kept_for_other_anthropic(model_id: str) -> None:
+    """Sonnet 4.5/4.6 and Opus <=4.6 accept toolSpec.strict — keep forwarding it."""
+    result = _bedrock_tools_pt(_STRICT_TOOL, model=model_id)
+    assert result[0]["toolSpec"]["strict"] is True, f"strict missing for {model_id}: {result[0]['toolSpec']}"
+
+
+@pytest.mark.parametrize(
+    "model_id",
+    [
+        "us.amazon.nova-micro-v1:0",
+        "meta.llama3-2-11b-instruct-v1:0",
+    ],
+)
+def test_bedrock_tools_pt_strict_dropped_for_non_anthropic(model_id: str) -> None:
+    """Non-Anthropic Bedrock families reject toolSpec.strict — must be dropped."""
+    result = _bedrock_tools_pt(_STRICT_TOOL, model=model_id)
+    assert "strict" not in result[0]["toolSpec"]
+
+
+def test_bedrock_converse_supports_strict_tools_helper() -> None:
+    """Direct check for the gate helper used by factory.py."""
+    assert bedrock_converse_supports_strict_tools("bedrock/us.anthropic.claude-opus-4-7") is False
+    assert bedrock_converse_supports_strict_tools("bedrock/us.anthropic.claude-opus-4-8") is False
+    assert bedrock_converse_supports_strict_tools("anthropic.claude-sonnet-4-5-20250929-v1:0") is True
+    assert bedrock_converse_supports_strict_tools("bedrock/us.anthropic.claude-opus-4-6") is True
+    assert bedrock_converse_supports_strict_tools("us.amazon.nova-micro-v1:0") is False
+    assert bedrock_converse_supports_strict_tools("") is False
+
+
+@pytest.mark.parametrize(
+    "cost_map_key",
+    [
+        "anthropic.claude-opus-4-7",
+        "us.anthropic.claude-opus-4-7",
+        "anthropic.claude-opus-4-8",
+        "us.anthropic.claude-opus-4-8",
+    ],
+)
+def test_strict_tools_flag_set_in_model_cost_map(cost_map_key: str) -> None:
+    """The gate is driven by ``bedrock_converse_supports_strict_tools: false`` in
+    ``model_prices_and_context_window.json``, not hardcoded model patterns."""
+    from litellm.litellm_core_utils.get_model_cost_map import GetModelCostMap
+
+    cost_map = GetModelCostMap.load_local_model_cost_map()
+    assert cost_map[cost_map_key]["bedrock_converse_supports_strict_tools"] is False

tests/test_litellm/test_utils.py

@@ -858,6 +858,7 @@ def test_aaamodel_prices_and_context_window_json_is_valid():
                     "type": "string",
                     "enum": ["low", "medium", "high", "max", "xhigh"],
                 },
+                "bedrock_converse_supports_strict_tools": {"type": "boolean"},
                 "tpm": {"type": "number"},
                 "provider_specific_entry": {"type": "object"},
                 "supported_endpoints": {