Pre-Release Changelog

Unreleased

Bug Fixes

• Params serialization: Custom paramsSerializer.encode functions now receive the active AxiosURLSearchParams instance as this, matching the intended encoder.call(this, value, defaultEncode) behavior during query string construction. (#11019)
• Runtime and types hardening: Guarded several edge-case crashes in cookie decoding, data URI parsing, form serialization, config merging, option validation, XHR cleanup, and Node HTTP URL serialization error handling. Type declarations now expose missing CanceledError, CancelToken, AxiosHeaders, SerializerOptions, and Cloudflare 52x status-code members that already exist at runtime. (#10959)
• HTTP Adapter - native env proxy: Avoid double-applying environment proxy handling when Node.js native HTTP proxy support is active for the selected agent. Axios still resolves env proxies itself when the selected agent is not using Node's proxyEnv support. (#10942, closes #7299)
• HTTP Adapter - socketPath: Path-only request URLs (e.g. '/foo') now work again with config.socketPath, fixing the TypeError [ERR_INVALID_URL] regression introduced in 1.7.4 when new URL() was added to the dispatch path. A synthetic http://localhost base is supplied only when an own socketPath is set, so absolute URLs, non-socket requests, and prototype-polluted socketPath values are unaffected. (#6611)

Documentation

• Request data defaults: Clarified that data is request-specific and is not inherited or deep-merged from global or instance defaults. Shared body fields should be added with a request interceptor or transformRequest, scoped carefully to avoid sending sensitive values to unintended endpoints.

Release Tracking

• Proxy Agent Streams: Guarded Node HTTP adapter TCP keep-alive setup so proxy agents that return generic Duplex streams do not throw when setKeepAlive is unavailable. (#10917, closes #10908)