Replace httpx with httpx2

dev-notes/architecture/codex-runtime-model-limits.md

@@ -118,7 +118,7 @@ rare.
 
 ## Testing
 
-Deterministic tests use `httpx.MockTransport` and a fake model-limit provider.
+Deterministic tests use `httpx2.MockTransport` and a fake model-limit provider.
 They cover:
 
 - authenticated Codex model-catalog URL and headers

dev-notes/architecture/oauth-provider-parity.md

@@ -98,7 +98,7 @@ the short-lived token.
 
 ## Validation and release process
 
-Deterministic tests use `httpx.MockTransport` and fake credentials. They cover:
+Deterministic tests use `httpx2.MockTransport` and fake credentials. They cover:
 
 - Anthropic refresh success and error redaction
 - Copilot device login, token exchange, Enterprise routing, untrusted URL

dev-notes/architecture/phase-18-provider-config-foundation.md

@@ -109,7 +109,7 @@ variable is not currently set.
 
 Provider HTTP timeouts are configurable through `timeout_seconds` in
 `~/.tau/providers.json`. The default OpenAI-compatible provider can also read
-`OPENAI_TIMEOUT_SECONDS`. The configured value is passed to the HTTPX streaming
+`OPENAI_TIMEOUT_SECONDS`. The configured value is passed to the HTTPX2 streaming
 client instead of keeping timeout behavior hardcoded in the provider adapter.
 
 Transient retry behavior is configurable through `max_retries` and

dev-notes/architecture/socks-proxy-support.md

@@ -1,6 +1,6 @@
 # SOCKS proxy support
 
-Tau uses `httpx` for provider requests, OAuth token refreshes, and startup update checks. `httpx` reads standard proxy environment variables such as `HTTP_PROXY`, `HTTPS_PROXY`, `ALL_PROXY`, and `NO_PROXY`.
+Tau uses `httpx2` for provider requests, OAuth token refreshes, and startup update checks. `httpx2` reads standard proxy environment variables such as `HTTP_PROXY`, `HTTPS_PROXY`, `ALL_PROXY`, and `NO_PROXY`.
 
 ## What changed
 
@@ -10,33 +10,33 @@ Issue #221 reported failures when the environment contained a generic SOCKS prox
 ALL_PROXY=socks://127.0.0.1:1080
 ```
 
-`httpx` does not accept the generic `socks://` scheme. It accepts explicit SOCKS schemes such as `socks5://` and `socks5h://`, and those require the optional SOCKS dependency.
+`httpx2` does not accept the generic `socks://` scheme. It accepts explicit SOCKS schemes such as `socks5://` and `socks5h://`, and those require the optional SOCKS dependency.
 
 Tau now:
 
-- installs `httpx[socks]` in the base package so `socksio` is available;
+- installs `httpx2[socks]` in the base package so `socksio` is available;
 - normalizes `socks://...` to `socks5://...` before constructing Tau-owned HTTP clients;
 - routes provider clients, OAuth token refresh clients, and update-check fetches through shared helpers in `tau_ai.http`.
 
 ## Why `socks://` maps to `socks5://`
 
-The generic scheme does not specify whether DNS lookup should happen locally or through the proxy. Tau treats it as SOCKS5 with local DNS resolution because that is the closest explicit `httpx` scheme and avoids silently changing DNS behavior beyond making the previously invalid URL usable.
+The generic scheme does not specify whether DNS lookup should happen locally or through the proxy. Tau treats it as SOCKS5 with local DNS resolution because that is the closest explicit `httpx2` scheme and avoids silently changing DNS behavior beyond making the previously invalid URL usable.
 
 Users who need proxy-side DNS resolution should set an explicit `socks5h://` URL.
 
 ## Future improvement: avoid temporary environment mutation
 
-The current helper temporarily normalizes proxy environment variables while constructing Tau-owned `httpx` clients. For the synchronous update-check helper, the normalization currently wraps the full `httpx.get(...)` call because `httpx.get` constructs and uses a short-lived client internally.
+The current helper temporarily normalizes proxy environment variables while constructing Tau-owned `httpx2` clients. For the synchronous update-check helper, the normalization currently wraps the full `httpx2.get(...)` call because `httpx2.get` constructs and uses a short-lived client internally.
 
 This is acceptable for the current low-concurrency startup update-check path, but environment variables are process-global state. If Tau later performs more concurrent networking around this helper, another thread or task could observe the normalized proxy value while the request is in progress.
 
 If this becomes a concern, prefer avoiding process environment mutation for request execution:
 
 1. normalize proxy values into local data;
-2. construct an explicit `httpx.Client` or `httpx.AsyncClient` with equivalent proxy configuration;
+2. construct an explicit `httpx2.Client` or `httpx2.AsyncClient` with equivalent proxy configuration;
 3. perform requests through that client without changing `os.environ` during request execution.
 
-When implementing that, preserve `NO_PROXY` semantics. `httpx` currently handles environment proxy discovery and no-proxy matching internally, so replacing it with explicit mounts/proxy configuration should include tests for:
+When implementing that, preserve `NO_PROXY` semantics. `httpx2` currently handles environment proxy discovery and no-proxy matching internally, so replacing it with explicit mounts/proxy configuration should include tests for:
 
 - `ALL_PROXY=socks://...` normalization;
 - `HTTP_PROXY` and `HTTPS_PROXY` handling;

dev-notes/hugging-face-response-provider-metadata.md

@@ -24,7 +24,7 @@ not expose provider selection or pinning controls in this change.
 
 ## Validation
 
-Focused tests use an `httpx.MockTransport` to simulate one failed response from
+Focused tests use an `httpx2.MockTransport` to simulate one failed response from
 one Inference Provider followed by a successful response from another. They
 verify that only the provider from the successful request becomes the final
 message's `response_provider`, while `provider` remains `huggingface`.

dev-notes/llama-cpp-phase-5.md

@@ -63,7 +63,7 @@ stale; Tau does not silently select the remaining model.
 
 ## How to test
 
-The deterministic suite uses `httpx.MockTransport` and fake credential/state
+The deterministic suite uses `httpx2.MockTransport` and fake credential/state
 stores. It covers endpoint safety, auth headers, cache/offline behavior,
 malformed discovery, metadata allowlisting, stale model handling, atomic state
 writes, orphan cleanup, reset, Doctor, real runtime registration, generation

dev-notes/llama-cpp-phase-7.md

@@ -74,7 +74,7 @@ search metadata.
 
 ## How to test
 
-All HTTP behavior is deterministic through `httpx.MockTransport`:
+All HTTP behavior is deterministic through `httpx2.MockTransport`:
 
 ```bash
 uv run pytest tests/test_llama_cpp_extension.py -q

plans/602-built-in-local-inference.md

@@ -1333,7 +1333,7 @@ Test:
 
 ### 15.5 llama.cpp fake HTTP server
 
-Use `httpx.MockTransport` or the transport injection already used by Tau. Cover:
+Use `httpx2.MockTransport` or the transport injection already used by Tau. Cover:
 
 - root URL normalization;
 - `/v1` normalization;

pyproject.toml

@@ -12,7 +12,7 @@ license-files = ["LICENSE"]
 requires-python = ">=3.12"
 dependencies = [
     "anyio>=4.0",
-    "httpx[socks]>=0.27",
+    "httpx2[socks]>=2.12.0",
     "packaging>=24.0",
     "pillow>=11.0",
     "pydantic>=2.11",

src/tau_ai/anthropic.py

@@ -6,7 +6,7 @@
 from json import loads
 from typing import Any, cast
 
-import httpx
+import httpx2
 
 from tau_agent.messages import (
     AgentMessage,
@@ -77,7 +77,7 @@ def __init__(
         self,
         config: AnthropicConfig,
         *,
-        client: httpx.AsyncClient | None = None,
+        client: httpx2.AsyncClient | None = None,
     ) -> None:
         self._config = config
         self._client = client
@@ -341,7 +341,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
                             finish_reason=finish_reason,
                         )
                         return
-                except httpx.HTTPError as exc:
+                except httpx2.HTTPError as exc:
                     if not emitted_content and self._should_retry(attempt):
                         delay = retry_delay_seconds(
                             attempt,
@@ -369,7 +369,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
 
         return iterator()
 
-    def _get_client(self) -> httpx.AsyncClient:
+    def _get_client(self) -> httpx2.AsyncClient:
         if self._client is None:
             self._client = create_async_client(timeout=self._config.timeout_seconds)
         return self._client

src/tau_ai/google.py

@@ -5,7 +5,7 @@
 from collections.abc import AsyncIterator, Mapping
 from json import JSONDecodeError, loads
 
-import httpx
+import httpx2
 
 from tau_agent.messages import (
     AgentMessage,
@@ -51,7 +51,7 @@ def __init__(
         self,
         config: OpenAICompatibleConfig,
         *,
-        client: httpx.AsyncClient | None = None,
+        client: httpx2.AsyncClient | None = None,
     ) -> None:
         self._config = config
         self._client = client
@@ -184,7 +184,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
                         for parser_event in parser.finalize():
                             yield parser_event
                         return
-                except httpx.HTTPError as exc:
+                except httpx2.HTTPError as exc:
                     if not parser.emitted_content and self._should_retry(attempt):
                         delay = retry_delay_seconds(
                             attempt,
@@ -206,7 +206,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
 
         return iterator()
 
-    def _get_client(self) -> httpx.AsyncClient:
+    def _get_client(self) -> httpx2.AsyncClient:
         if self._client is None:
             self._client = create_async_client(timeout=self._config.timeout_seconds)
         return self._client

src/tau_ai/http.py

@@ -7,7 +7,7 @@
 from contextlib import contextmanager
 from typing import Any
 
-import httpx
+import httpx2
 
 _PROXY_ENV_VARS = (
     "HTTP_PROXY",
@@ -20,9 +20,9 @@
 
 
 def normalize_proxy_url(proxy_url: str) -> str:
-    """Return an httpx-compatible proxy URL.
+    """Return an httpx2-compatible proxy URL.
 
-    Some environments use ``socks://`` as a generic SOCKS proxy scheme. httpx
+    Some environments use ``socks://`` as a generic SOCKS proxy scheme. httpx2
     accepts explicit SOCKS versions (for example ``socks5://`` and
     ``socks5h://``), but rejects the generic scheme before it can make a
     request. Treat the generic form as SOCKS5 so Tau can honor these proxy
@@ -36,7 +36,7 @@ def normalize_proxy_url(proxy_url: str) -> str:
 
 @contextmanager
 def normalized_proxy_environment() -> Iterator[None]:
-    """Temporarily normalize proxy environment variables for httpx construction."""
+    """Temporarily normalize proxy environment variables for httpx2 construction."""
 
     original: dict[str, str | None] = {}
     changed = False
@@ -62,18 +62,18 @@ def normalized_proxy_environment() -> Iterator[None]:
                     os.environ[name] = value
 
 
-def create_async_client(**kwargs: Any) -> httpx.AsyncClient:
-    """Create an ``httpx.AsyncClient`` with Tau's proxy normalization applied."""
+def create_async_client(**kwargs: Any) -> httpx2.AsyncClient:
+    """Create an ``httpx2.AsyncClient`` with Tau's proxy normalization applied."""
 
     with normalized_proxy_environment():
-        return httpx.AsyncClient(**kwargs)
+        return httpx2.AsyncClient(**kwargs)
 
 
 def get_json(url: str, *, timeout: float, follow_redirects: bool = False) -> dict[str, object]:
     """Fetch a JSON object with Tau's proxy normalization applied."""
 
     with normalized_proxy_environment():
-        response = httpx.get(url, timeout=timeout, follow_redirects=follow_redirects)
+        response = httpx2.get(url, timeout=timeout, follow_redirects=follow_redirects)
     response.raise_for_status()
     data = response.json()
     if not isinstance(data, dict):

src/tau_ai/mistral.py

@@ -6,7 +6,7 @@
 from json import JSONDecodeError, dumps, loads
 from typing import Any, Protocol
 
-import httpx
+import httpx2
 
 from tau_agent.messages import (
     AgentMessage,
@@ -51,7 +51,7 @@ def __init__(
         self,
         config: OpenAICompatibleConfig,
         *,
-        client: httpx.AsyncClient | None = None,
+        client: httpx2.AsyncClient | None = None,
     ) -> None:
         self._config = config
         self._client = client
@@ -174,7 +174,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
                         for parser_event in parser.finalize():
                             yield parser_event
                         return
-                except httpx.HTTPError as exc:
+                except httpx2.HTTPError as exc:
                     if not parser.emitted_content and self._should_retry(attempt):
                         delay = retry_delay_seconds(
                             attempt,
@@ -196,7 +196,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
 
         return iterator()
 
-    def _get_client(self) -> httpx.AsyncClient:
+    def _get_client(self) -> httpx2.AsyncClient:
         if self._client is None:
             self._client = create_async_client(timeout=self._config.timeout_seconds)
         return self._client

src/tau_ai/openai_codex.py

@@ -8,7 +8,7 @@
 from platform import machine, release, system
 from typing import Any
 
-import httpx
+import httpx2
 
 from tau_agent.messages import (
     AgentMessage,
@@ -93,7 +93,7 @@ def __init__(
         self,
         config: OpenAICodexConfig,
         *,
-        client: httpx.AsyncClient | None = None,
+        client: httpx2.AsyncClient | None = None,
     ) -> None:
         self._config = config
         self._client = client
@@ -280,7 +280,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
                         if not await wait_for_retry(delay, signal=signal):
                             return
                         continue
-                except httpx.HTTPError as exc:
+                except httpx2.HTTPError as exc:
                     if not emitted_content and self._should_retry(attempt):
                         delay = retry_delay_seconds(
                             attempt,
@@ -311,7 +311,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
 
         return iterator()
 
-    def _get_client(self) -> httpx.AsyncClient:
+    def _get_client(self) -> httpx2.AsyncClient:
         if self._client is None:
             self._client = create_async_client(timeout=self._config.timeout_seconds)
         return self._client
@@ -502,7 +502,7 @@ def _tool_to_codex(tool: AgentTool) -> dict[str, JSONValue]:
 
 
 async def _codex_provider_events(
-    response: httpx.Response,
+    response: httpx2.Response,
     *,
     signal: CancellationToken | None,
 ) -> AsyncIterator[ProviderEvent]:
@@ -677,7 +677,7 @@ async def _codex_provider_events(
     )
 
 
-async def _iter_sse_objects(response: httpx.Response) -> AsyncIterator[dict[str, JSONValue]]:
+async def _iter_sse_objects(response: httpx2.Response) -> AsyncIterator[dict[str, JSONValue]]:
     data_lines: list[str] = []
     async for line in response.aiter_lines():
         stripped = line.strip()

src/tau_ai/openai_compatible.py

@@ -15,7 +15,7 @@
 from json import JSONDecodeError, dumps, loads
 from typing import Any, Protocol
 
-import httpx
+import httpx2
 
 from tau_agent.messages import (
     AgentMessage,
@@ -79,7 +79,7 @@ def __init__(
         self,
         config: OpenAICompatibleConfig,
         *,
-        client: httpx.AsyncClient | None = None,
+        client: httpx2.AsyncClient | None = None,
     ) -> None:
         self._config = config
         self._client = client
@@ -347,7 +347,7 @@ async def iterator() -> AsyncIterator[ProviderEvent]:
                         for parser_event in final_events:
                             yield parser_event
                         return
-                except httpx.HTTPError as exc:
+                except httpx2.HTTPError as exc:
                     if not parser.emitted_content and self._should_retry(attempt):
                         delay = retry_delay_seconds(
                             attempt,
@@ -392,7 +392,7 @@ def _session_affinity_format(self, *, responses: bool) -> str | None:
         value = self._config.compat.get("sessionAffinityFormat")
         return value if isinstance(value, str) else "openai"
 
-    def _get_client(self) -> httpx.AsyncClient:
+    def _get_client(self) -> httpx2.AsyncClient:
         if self._client is None:
             self._client = create_async_client(timeout=self._config.timeout_seconds)
         return self._client
@@ -403,7 +403,7 @@ def _should_retry(self, attempt: int, *, status_code: int | None = None) -> bool
         return status_code is None or _is_transient_status(status_code)
 
 
-def _response_header_value(response: httpx.Response, header_name: str | None) -> str | None:
+def _response_header_value(response: httpx2.Response, header_name: str | None) -> str | None:
     """Return one normalized response metadata header when configured."""
     if header_name is None:
         return None

src/tau_coding/built_in_extensions.py

@@ -7,7 +7,7 @@
 from inspect import iscoroutinefunction
 from typing import TYPE_CHECKING
 
-import httpx
+import httpx2
 
 from tau_coding.credentials import CredentialStore
 from tau_coding.paths import TauPaths
@@ -29,7 +29,7 @@ class BuiltInExtensionContext:
     paths: TauPaths
     credential_store: CredentialStore
     environment: Mapping[str, str]
-    http_client: httpx.AsyncClient | None = None
+    http_client: httpx2.AsyncClient | None = None
 
 
 BuiltInExtensionSetup = Callable[["ExtensionAPI"], None]