release: 4.1.0

[stainless-app]

Automated Release PR

4.1.0 (2026-01-30)

Full Changelog: v4.0.0...v4.1.0

Features

• api: update via SDK Studio (#61) (9c0c551)
• clean up environment call outs (696f18b)
• client: add custom JSON encoder for extended type support (87eaded)
• client: add follow_redirects request option (6eb41c9)
• client: add support for aiohttp (6f6ddd9)
• client: add support for binary request streaming (41c399b)
• client: allow passing NotGiven for body (#67) (3ad7f25)
• client: send X-Stainless-Read-Timeout header (#63) (a594c75)
• client: support file upload requests (fde965a)
• improve future compat with pydantic v3 (bccbddf)
• types: replace List[str] with SequenceNotStr in params (0578887)

Bug Fixes

• asyncify on non-asyncio runtimes (#66) (ca310cd)
• avoid newer type syntax (db10820)
• ci: correct conditional (66eb0ef)
• ci: ensure pip is always available (#78) (d3d295a)
• ci: release-doctor — report correct token name (65cdccf)
• ci: remove publishing patch (#79) (493f504)
• client: close streams without requiring full consumption (e783145)
• client: correctly parse binary response | stream (3924997)
• client: don't send Content-Type header on GET requests (6bcbc4e)
• client: mark some request bodies as optional (3ad7f25)
• compat with Python 3.14 (f7d6103)
• compat: update signatures of model_dump and model_dump_json for Pydantic v1 (898ca7b)
• ensure streams are always closed (f89af68)
• package: support direct resource imports (ad2d130)
• parsing: correctly handle nested discriminated unions (cd511d2)
• parsing: ignore empty metadata (bdd8ead)
• parsing: parse extra field types (470d8a8)
• perf: optimize some hot paths (7cc4937)
• perf: skip traversing types for NotGiven values (38509ba)
• pydantic v1: more robust ModelField.annotation check (3dc3480)
• tests: fix: tests which call HTTP endpoints directly with the example parameters (539215f)
• types: allow pyright to infer TypedDict types within SequenceNotStr (84b4806)
• types: handle more discriminated union shapes (#77) (8b6dcf0)
• use async_to_httpx_files in patch method (6bfd0c0)

Chores

• add Python 3.14 classifier and testing (c172e9c)
• broadly detect json family of content-type headers (febefbc)
• bump httpx-aiohttp version to 0.1.9 (7aeb4c8)
• ci: add timeout thresholds for CI jobs (d5cbcd0)
• ci: change upload type (d7e4405)
• ci: enable for pull requests (1ea6fbc)
• ci: fix installation instructions (6291f4a)
• ci: only run for pushes and fork pull requests (5d00f3e)
• ci: only use depot for staging repos (19ee773)
• ci: upgrade actions/github-script (bdad5ed)
• ci: upload sdks to package manager (598ec7e)
• client: minor internal fixes (1e29d3b)
• deps: mypy 1.18.1 has a regression, pin to 1.17 (fd940b6)
• do not install brew dependencies in ./scripts/bootstrap by default (67c48f0)
• docs: grammar improvements (540e711)
• docs: remove reference to rye shell (ec32daa)
• docs: update client docstring (#71) (b41543a)
• docs: use environment variables for authentication in code snippets (ff7f0ef)
• fix typos (#80) (c1576cc)
• internal/tests: avoid race condition with implicit client cleanup (d3a5435)
• internal: add --fix argument to lint script (0b1e68e)
• internal: add missing files argument to base client (5547d1b)
• internal: add Sequence related utils (5f815ef)
• internal: avoid errors for isinstance checks on proxies (5dc0949)
• internal: base client updates (0ac179a)
• internal: bump pinned h11 dep (6cafe07)
• internal: bump pyright version (81c2baf)
• internal: bump rye to 0.44.0 (#76) (21a20b3)
• internal: change ci workflow machines (656643d)
• internal: codegen related update (0b4efb7)
• internal: codegen related update (2f8fbc4)
• internal: codegen related update (d6d5a1d)
• internal: codegen related update (a145cee)
• internal: codegen related update (#75) (db19786)
• internal: detect missing future annotations with ruff (23b94ed)
• internal: expand CI branch coverage (7fd1145)
• internal: fix devcontainers setup (#68) (97b7254)
• internal: fix list file params (1b5e333)
• internal: fix ruff target version (1437b86)
• internal: fix type traversing dictionary params (#64) (1322c80)
• internal: grammar fix (it's -> its) (8b1cdb7)
• internal: import reformatting (8a3f6f0)
• internal: minor type handling changes (#65) (7e69125)
• internal: move mypy configurations to pyproject.toml file (f87b268)
• internal: properly set pydantic_private (#69) (bc25b84)
• internal: reduce CI branch coverage (2492996)
• internal: refactor retries to not use recursion (055e329)
• internal: remove extra empty newlines (#74) (3d90dff)
• internal: remove trailing character (#81) (4cfa80b)
• internal: remove unused http client options forwarding (#72) (69a44e3)
• internal: slight transform perf improvement (#82) (5498eaf)
• internal: update actions/checkout version (54d6bd9)
• internal: update comment in script (103820e)
• internal: update conftest.py (83531b4)
• internal: update models test (421a2b5)
• internal: update pydantic dependency (5dd09a4)
• internal: update pyright exclude list (f306088)
• internal: update pyright settings (2d267e1)
• package: drop Python 3.8 support (95ca18d)
• package: mark python 3.13 as supported (06ad64f)
• project: add settings file for vscode (6754b39)
• readme: fix version rendering on pypi (b1e9e51)
• readme: update badges (f3f214f)
• speedup initial import (3b3f4e6)
• tests: add tests for httpx client instantiation & proxies (5e172cd)
• tests: run tests in parallel (497b381)
• tests: simplify get_platform test (ef07d85)
• tests: skip some failing tests on the latest python versions (39d037c)
• types: change optional parameter type from NotGiven to Omit (14cb9a9)
• update @stainless-api/prism-cli to v5.15.0 (d766a01)
• update github action (d0f9d9e)
• update lockfile (77726a0)

Documentation

• client: fix httpx.Timeout documentation reference (3341b85)
• update URLs from stainlessapi.com to stainless.com (#70) (08062c4)

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Note

Medium Risk
Touches core HTTP request/response plumbing (retries, headers, streaming, body encoding) and packaging requirements (Python >=3.9), which could affect client behavior and compatibility across environments.

Overview
Updates the SDK release to 4.1.0 (manifest, pyproject.toml, and CHANGELOG.md) and refreshes docs/metadata (new docs URLs, requirements now Python >=3.9, new aiohttp usage section, updated security contact/email).

Client/runtime changes: adds an optional aiohttp HTTP backend (DefaultAioHttpClient + [aiohttp] extra), supports sending raw/binary request bodies via a new content parameter (with validation and deprecations for bytes-in-body), and tweaks request construction/headers (no Content-Type on GET, add X-Stainless-Read-Timeout, idempotency key handling). Retries are refactored from recursion to a loop; SSE streams now ensure responses are closed even if not fully consumed.

Type/compat/perf: introduces explicit not_given/omit singletons, improves Pydantic v1/v2/v3 compatibility (datetime parsing utilities, model dump signatures, discriminated-union parsing, extra-field typing), and adds small performance caches in transform/type utilities.

Tooling/CI: upgrades Rye to 0.44.0, adds Node to devcontainers, removes .vscode from .gitignore and adds VS Code settings, updates workflows (checkout v6, timeouts, branch ignores), adds a build job that can upload artifacts via OIDC, updates Prism CLI usage, makes bootstrap’s Homebrew installs interactive, runs pytest in parallel, and adds ./scripts/lint --fix.

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