A new client with the given middleware appended after this client's middleware. Convenience for applying extra middleware to a single request

True only for the base ``Anthropic`` / ``AsyncAnthropic`` classes, not subclasses. Subclasses (``AnthropicAWS``, ``AnthropicFoundry``) have their

Generate a MessageParam by calling tool functions with any tool use blocks from the last message. Note the tool call response is cached, repe

Service a single, already-claimed work item without the poll loop. Builds the per-session :class:`AgentToolContext` (workdir from this

The ``x-stainless-helper: <value>`` header dict, for passing into a ``merge_headers`` call or as ``extra_headers``/``default_headers``. Typin

A fallback hop that contributes one text block, then refuses with a fresh token.

A byte-iterator over the decoded response content. This automatically handles gzip, deflate and brotli encoded responses.

List available models. The Models API response can be used to determine which models are available for use in the API. More

A client with the default (non-strict) response validation. The fixture wire's terminal refusal delta self-reports a `{type: "message"}` iter

Convert an MCP tool to a sync runnable tool for ``tool_runner()``. Example:: from anthropic.lib.tools.mcp import mcp_tool tools

Pretty print an object to a string

Add a pydantic config for the given type. Note: this is a no-op on Pydantic v1.

A CUSTOM (user-defined) tool call — the agent emits ``agent.custom_tool_use`` rather than ``agent.tool_use`` for these.

Pull a single item from a sync iterator; assert there was one.

Return an ``httpx.Client``, lazily creating (and tracking) one we own.

Read and cache the config file, resolving ``base_url`` and ``credentials_path``.

Return the first non-None value from the given env vars, or None.

Reject non-``https://`` token-endpoint URLs. Localhost is allowed for testing so ``base_url="http://localhost:8080"`` works against a local `

Create ``path`` and any missing parents with ``mode``, regardless of umask. ``Path.mkdir(parents=True, mode=...)`` and ``os.makedirs(mode=...)``

True if ``child`` is ``root`` or a path inside it (both already resolved).

Given an iterator that yields raw binary data, iterate over it & yield every event encountered

Ensure that the signature of the second function matches the first.

Construct a BaseModel class without validation. This is useful for cases where you need to instantiate a `BaseModel` from an API response as

Close the response and release the connection. Automatically called if the response body is read to completion.

Close the response and release the connection. Automatically called if the response body is read to completion.

Create a new client instance re-using the same options given to the current client with optional overriding.

Create a new client instance re-using the same options given to the current client with optional overriding.

Whether or not the response body has been closed. If this is False then there is response data that has not been read yet. You must e

Return whether the provided argument is an instance of `TypeAliasType`. ```python type Int = int is_type_alias_type(Int) # > True

Convert an MCP prompt message to an Anthropic ``BetaMessageParam``.

Add single quotation marks around the given string. Does *not* do any escaping.

Dispatch or resolve a gated call according to the user's verdict. The idle-clock hold accounting lives here: a denial drops the held

Resolve the config directory. ``ANTHROPIC_CONFIG_DIR`` env var → platform default. Platform defaults: * Linux & macOS: ``~/.config/ant

Map a filesystem ``OSError`` to a consistent, runtime-independent message. The raw ``OSError`` string is platform-specific (``[Errno 2] ENOENT: .

If the given type is an `Annotated` type then it is returned, if not `None` is returned. This also unwraps the type when applicable, e.g. `Requir

``json.dumps`` with ``SecretStr`` values unwrapped at dump time. Returns bytes so call sites can pass the result inline (request content, ``o

Truncate a token-endpoint error body for safe inclusion in an exception.

base_url precedence: top-level config field → bound (the owning client's base_url, via :meth:`bind_base_url`) → default. Validated aga

The synthetic `fallback` content block marking one model boundary.