release: 0.110.0

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "0.109.2"
+  ".": "0.110.0"
 }

.stats.yml

@@ -1,4 +1,4 @@
 configured_endpoints: 116
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/anthropic/anthropic-04d2899e1e4dd48e29347b98f1265e6345ee20b75e29c12eca1068a8f7c61095.yml
-openapi_spec_hash: 989d596f7660ce55a7cea748a9292b45
-config_hash: 221b6331246cafc1f7ff1861d35a3640
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/anthropic/anthropic-2ecf157aa324d82fa8f3636a325aea5bd96ecab93193f6e37864ebe665c48685.yml
+openapi_spec_hash: 29873ea69a87e047c4f742a960648bf0
+config_hash: 48f7cbc6648bf7f1e6c68ad3dab477fc

CHANGELOG.md

@@ -1,5 +1,20 @@
 # Changelog
 
+## 0.110.0 (2026-06-18)
+
+Full Changelog: [v0.109.2...v0.110.0](https://github.com/anthropics/anthropic-sdk-python/compare/v0.109.2...v0.110.0)
+
+### Features
+
+* **api:** add support for new code_execution_20260120 tool ([5e23212](https://github.com/anthropics/anthropic-sdk-python/commit/5e23212dc0883174c879b97ef8e7e33ead4e8da5))
+
+
+### Bug Fixes
+
+* append x-stainless-helper across header merges instead of clobbering ([#105](https://github.com/anthropics/anthropic-sdk-python/issues/105)) ([922558e](https://github.com/anthropics/anthropic-sdk-python/commit/922558e2ce52e18863dab27bcc04067068827364))
+* **bedrock:** preserve stream event type ([#1682](https://github.com/anthropics/anthropic-sdk-python/issues/1682)) ([b27e343](https://github.com/anthropics/anthropic-sdk-python/commit/b27e3439699174dbc41e34e2d6ef5cb1e2930c18))
+* **helpers:** single source of truth for x-stainless-helper key + closed value vocabulary ([#95](https://github.com/anthropics/anthropic-sdk-python/issues/95)) ([e6f7a56](https://github.com/anthropics/anthropic-sdk-python/commit/e6f7a56bb624f4c946cb15ba7973fd6fe052e10f))
+
 ## 0.109.2 (2026-06-15)
 
 Full Changelog: [v0.109.1...v0.109.2](https://github.com/anthropics/anthropic-sdk-python/compare/v0.109.1...v0.109.2)

api.md

@@ -56,6 +56,7 @@ from anthropic.types import (
     CodeExecutionTool20250522,
     CodeExecutionTool20250825,
     CodeExecutionTool20260120,
+    CodeExecutionTool20260521,
     CodeExecutionToolResultBlock,
     CodeExecutionToolResultBlockContent,
     CodeExecutionToolResultBlockParam,
@@ -347,6 +348,7 @@ from anthropic.types.beta import (
     BetaCodeExecutionTool20250522,
     BetaCodeExecutionTool20250825,
     BetaCodeExecutionTool20260120,
+    BetaCodeExecutionTool20260521,
     BetaCodeExecutionToolResultBlock,
     BetaCodeExecutionToolResultBlockContent,
     BetaCodeExecutionToolResultBlockParam,
@@ -382,6 +384,7 @@ from anthropic.types.beta import (
     BetaFallbackInfoParam,
     BetaFallbackMessageIterationUsage,
     BetaFallbackParam,
+    BetaFallbackRefusalTrigger,
     BetaFileDocumentSource,
     BetaFileImageSource,
     BetaImageBlockParam,
@@ -1155,6 +1158,7 @@ from anthropic.types.beta import (
     BetaWebhookSessionThreadCreatedEventData,
     BetaWebhookSessionThreadIdledEventData,
     BetaWebhookSessionThreadTerminatedEventData,
+    BetaWebhookSessionUpdatedEventData,
     BetaWebhookVaultArchivedEventData,
     BetaWebhookVaultCreatedEventData,
     BetaWebhookVaultCredentialArchivedEventData,

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "anthropic"
-version = "0.109.2"
+version = "0.110.0"
 description = "The official Python library for the anthropic API"
 dynamic = ["readme"]
 license = "MIT"

src/anthropic/_base_client.py

@@ -456,7 +456,7 @@ def _make_status_error(
 
     def _build_headers(self, options: FinalRequestOptions, *, retries_taken: int = 0) -> httpx.Headers:
         custom_headers = options.headers or {}
-        headers_dict = _merge_mappings(
+        merged_headers = merge_headers(
             {
                 "x-stainless-timeout": str(options.timeout.read)
                 if isinstance(options.timeout, Timeout)
@@ -465,6 +465,7 @@ def _build_headers(self, options: FinalRequestOptions, *, retries_taken: int = 0
             },
             custom_headers,
         )
+        headers_dict = _strip_omit(merged_headers)
         self._validate_headers(headers_dict, custom_headers)
 
         # headers are case-insensitive while dictionaries are not.
@@ -2538,6 +2539,11 @@ def get_architecture() -> Arch:
     return "unknown"
 
 
+def _strip_omit(mapping: Mapping[_T_co, Union[_T, Omit]]) -> Dict[_T_co, _T]:
+    """Drop entries whose value is an `Omit` removal marker."""
+    return {key: value for key, value in mapping.items() if not isinstance(value, Omit)}
+
+
 def _merge_mappings(
     obj1: Mapping[_T_co, Union[_T, Omit]],
     obj2: Mapping[_T_co, Union[_T, Omit]],
@@ -2546,8 +2552,65 @@ def _merge_mappings(
 
     In cases with duplicate keys the second mapping takes precedence.
     """
-    merged = {**obj1, **obj2}
-    return {key: value for key, value in merged.items() if not isinstance(value, Omit)}
+    return _strip_omit({**obj1, **obj2})
+
+
+# Append-on-merge header support (hand-written, upstream to Stainless).
+#
+# Headers whose values accumulate across a merge instead of the later mapping's
+# value replacing the earlier one. When multiple mappings set one of these, the
+# values are concatenated into a single comma-separated value (order-preserving,
+# deduplicated) rather than clobbered.
+_APPEND_HEADERS = frozenset({"x-stainless-helper"})
+
+
+def _append_header_value(existing: str, addition: str) -> str:
+    """Append `addition` to a comma-separated header value, skipping tokens that
+    are already present so the same helper isn't recorded twice.
+
+    Values are joined with `", "`, the same format `lib._stainless_helpers` uses
+    when it builds the `x-stainless-helper` header.
+    """
+    tokens = [token for token in (raw.strip() for raw in existing.split(",")) if token]
+    for token in (raw.strip() for raw in addition.split(",")):
+        if token and token not in tokens:
+            tokens.append(token)
+    return ", ".join(tokens)
+
+
+def merge_headers(*mappings: Mapping[str, Union[str, Omit]]) -> Dict[str, str]:
+    """Merge header mappings, with later mappings taking precedence on a key
+    clash, exactly like `_merge_mappings`.
+
+    The exception is the headers in `_APPEND_HEADERS`: those keys are matched
+    case-insensitively (and stored under their lowercase form) and their string
+    values accumulate into a single comma-separated, deduplicated value instead
+    of the later one overriding the earlier one.
+
+    `Omit` values are preserved (they mark a header for removal and are only
+    dropped at request-build time, e.g. with `_strip_omit`); the
+    `Dict[str, str]` return type is the same fudge the rest of the header
+    plumbing already uses for `Omit`-bearing header mappings.
+    """
+    merged: Dict[str, Union[str, Omit]] = {}
+    for mapping in mappings:
+        for key, value in mapping.items():
+            lower = key.lower()
+            if lower not in _APPEND_HEADERS:
+                merged[key] = value
+                continue
+
+            # Append headers are stored under their lowercase key so every
+            # case-variant lands on (and appends to) the same entry.
+            existing = merged.get(lower)
+            if isinstance(existing, str) and isinstance(value, str):
+                merged[lower] = _append_header_value(existing, value)
+            else:
+                # `Omit` (removal) can't take part in an append; the later
+                # value overrides, as it does for any other header.
+                merged[lower] = value
+
+    return cast("Dict[str, str]", merged)
 
 
 def _middleware_entry_mode(request: APIRequest) -> Literal["raw", "stream", "true"] | None:

src/anthropic/_client.py

@@ -34,6 +34,7 @@
     DEFAULT_MAX_RETRIES,
     SyncAPIClient,
     AsyncAPIClient,
+    merge_headers,
 )
 
 # --- credentials support (hand-written, upstream to Stainless) ---
@@ -448,7 +449,7 @@ def copy(
 
         headers = self._custom_headers
         if default_headers is not None:
-            headers = {**headers, **default_headers}
+            headers = merge_headers(headers, default_headers)
         elif set_default_headers is not None:
             headers = set_default_headers
 
@@ -861,7 +862,7 @@ def copy(
 
         headers = self._custom_headers
         if default_headers is not None:
-            headers = {**headers, **default_headers}
+            headers = merge_headers(headers, default_headers)
         elif set_default_headers is not None:
             headers = set_default_headers
 

src/anthropic/_version.py

@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "anthropic"
-__version__ = "0.109.2"  # x-release-please-version
+__version__ = "0.110.0"  # x-release-please-version

src/anthropic/lib/_scoped_client.py

@@ -13,25 +13,21 @@
 
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Dict, Literal, TypeVar, cast
+from typing import TYPE_CHECKING, Dict, TypeVar, cast
+
+from ._stainless_helpers import STAINLESS_HELPER_HEADER, StainlessHelperHeaderValue
 
 if TYPE_CHECKING:
     from .._client import Anthropic, AsyncAnthropic
 
 
-__all__ = ["HelperTag", "_copy_client_with_bearer_auth"]
-
-
-# The closed set of ``x-stainless-helper`` telemetry tags the runner helpers
-# stamp on outgoing requests. Constrained via ``Literal`` so a typo at any
-# call site is a type error rather than silently mistagged telemetry.
-HelperTag = Literal["environments-work-poller", "environments-worker", "session-tool-runner"]
+__all__ = ["_copy_client_with_bearer_auth"]
 
 
 ClientT = TypeVar("ClientT", "Anthropic", "AsyncAnthropic")
 
 
-def _copy_client_with_bearer_auth(client: ClientT, *, auth_token: str, helper: HelperTag) -> ClientT:
+def _copy_client_with_bearer_auth(client: ClientT, *, auth_token: str, helper: StainlessHelperHeaderValue) -> ClientT:
     """Return a copy of ``client`` authenticated with ``auth_token`` as Bearer.
 
     The returned sub-client inherits the parent's full configuration via
@@ -61,7 +57,7 @@ def _copy_client_with_bearer_auth(client: ClientT, *, auth_token: str, helper: H
     scoped = client.copy(
         auth_token=auth_token,
         credentials=None,
-        default_headers={"x-stainless-helper": helper},
+        default_headers={STAINLESS_HELPER_HEADER: helper},
     )
     scoped.api_key = None
     # ``_custom_headers`` is typed as ``Mapping[str, str]`` (immutable