0.9.0-preview.10

The packages target netstandard2.0, net472, net10.0, and net11.0: net8.0 and net9.0
leave ahead of their end of support, and net11.0 joins on its go-live release candidate. A
project on .NET 8 or 9 still installs the packages through the netstandard2.0 asset, now with a
build warning. The pin moves to upstream release tag v2.0.29, which adds provider compatibility
defaults, request-body encoding and top-level config policies. OpenCodeServer.Exited reports how
a started server ended, and on Windows a server's exit is observed on the operating system's own
wait thread, so a busy host no longer reports a crashed start as a closed stdout. The breaking
changes come first: besides the target frameworks, OpenCodeServerOptions refuses an out-of-range
timeout when it is set, IOpenCodeClientOptions is removed,
OpenCodeStreamFailureException.Cause is now Causes, and PersistentPtyReplayBounds takes
camelCase constructor parameters.

💥 Breaking changes

• The packages target netstandard2.0, net472, net10.0, and net11.0. net8.0 and
  net9.0 leave ahead of their end of support on 2026-11-10, and net11.0 joins on its go-live
  release candidate. 0.9.0-preview.9 is the last version with net8.0 and net9.0 assets. A
  net8.0 or net9.0 project still installs the packages through the netstandard2.0 asset, now
  with a build warning, because that runtime is not one the packages are tested on; set
  <SuppressTfmSupportBuildWarnings>true</SuppressTfmSupportBuildWarnings> to silence it, or move
  the project to net10.0 or later. A project that treats warnings as errors fails its build on it
  until it does one or the other.
• OpenCodeServerOptions refuses an out-of-range timeout when it is set. ReadinessTimeout
  takes a value above zero and at most int.MaxValue milliseconds, or
  Timeout.InfiniteTimeSpan to wait until the start's cancellation token fires;
  GracefulShutdownTimeout takes zero to int.MaxValue milliseconds. A value outside that range
  throws ArgumentOutOfRangeException from the setter. A zero or negative readiness timeout and a
  negative grace were refused by OpenCodeServer.StartAsync before; a value past the ceiling was
  accepted and failed only after the server had been spawned.
• IOpenCodeClientOptions is removed. No public API accepted it, and every option added
  later would have broken its implementers, because net472 and netstandard2.0 have no default
  interface members. Configure clients through OpenCodeClientOptions, which a client still
  snapshots at construction. Code that declared a variable or parameter as
  IOpenCodeClientOptions uses OpenCodeClientOptions instead.
• OpenCodeStreamFailureException.Cause is now Causes. It is a list of causes, so the name
  is now plural. The constructor parameter is now causes as well. Read failure.Causes where
  you read failure.Cause, and pass causes: where you named the argument.
• PersistentPtyReplayBounds takes camelCase constructor parameters. They are
  requestedOffset, availableOffset, endOffset and truncated, like the other frame types'
  constructors. The properties keep their names, and positional construction, with and
  deconstruction are unchanged. Only a call that named an argument (RequestedOffset: 0) changes.

✨ Added

• OpenCodeServer.Exited reports how a started server ended. The task completes with an
  OpenCodeServerExit. It holds an exit code (on Windows the full 32-bit code), a terminating
  signal by name and number, or Unknown when the exit status could not be read, for example
  because something else reaped the server. It completes whether the server ended on its own or
  disposal ended it, once its output has ended or one second after the exit, as upstream's
  exited does. It never faults. On a handle from
  DiscoverAsync or EnsureAsync it throws InvalidOperationException, because that handle owns
  no process.
• The accepted snapshot moved to upstream release tag v2.0.29
  (042d0832f5f3a73eaa039a58a7d565776f6d4290), published as @opencode/cli@2.0.29; install it
  with npm install -g @opencode/cli@2.0.29. It adds and changes no operation, so all 142 remain
  callable.
• Provider compatibility defaults. ProviderInfo.Compatibility and
  ConfigProvider.Compatibility carry a ProviderCompatibility, the defaults a provider's models
  inherit: ReasoningField, RequireReasoning, MaxTokensField, RequireFinishReason,
  RequireAssistantAfterTool, SupportsPromptCacheKey, and CacheFormat.
• Prompt-cache marker format. ModelCompatibility.CacheFormat and
  ProviderCompatibility.CacheFormat name the marker syntax the endpoint accepts, as the new
  ModelCacheFormat enum (Anthropic, Alibaba).
• Request-body encoding. ProviderSettings.Encoding, ConfigProviderSettings.Encoding,
  ModelSettings.Encoding, and ConfigModelSettings.Encoding name the compression upstream applies
  to the provider request body, as the new ProviderEncoding enum (Zstd, Gzip, None).
• Top-level config policies. ConfigInfo.Policies carries the ordered policies that control
  access to providers, tools, and integrations, as the new ConfigInfoPolicies (Action,
  Resource, Effect) with the new ConfigInfoPoliciesAction (ProviderUse, ToolUse,
  IntegrationUse) and ConfigInfoPoliciesEffect (Allow, Deny) enums. Upstream deprecates
  experimental.policies: a 2.0.29 server reports those policies here, and
  ConfigInfoExperimental.Policies stays null.

🔧 Changes

• The packages depend on the .NET 10.0.13 servicing builds of their dependencies.
  OpenCodeDotNet.Sdk requires System.Text.Json, Microsoft.Bcl.AsyncInterfaces,
  Microsoft.Bcl.Memory, Microsoft.Bcl.TimeProvider, System.Collections.Immutable, and
  System.Threading.Channels 10.0.13 on netstandard2.0 and net472, up from 10.0.11; its
  net10.0 and net11.0 assets declare no dependency. OpenCodeDotNet.Sdk.Extensions requires
  Microsoft.Extensions.DependencyInjection.Abstractions and
  Microsoft.Extensions.Options.ConfigurationExtensions 10.0.13 on every target, up from 10.0.10.
  No security advisory covers the versions they replace. A project that references one of these
  packages directly at a lower version must raise it, or restore reports a package downgrade
  (NU1605, an error by default).

• A server that does not report readiness in time fails with the timeout as the inner
  exception. The OpenCodeServerException that OpenCodeServer.StartAsync throws then carries
  the readiness bound's OperationCanceledException as its InnerException, which was null.

• A settings encoding member is read as the typed Encoding. On ProviderSettings,
  ConfigProviderSettings, ModelSettings, and ConfigModelSettings it is no longer in
  AdditionalProperties, where 0.9.0-preview.9 kept it as an undeclared member.

• The source is laid out in feature folders, and the internal namespaces are flattened into
  OpenCode.Sdk.Internal. The public API is unchanged, byte for byte. Only the names of internal
  types differ, as a stack trace or reflection shows them.

🐛 Fixes

• On a busy Windows host, a server's exit is no longer reported late. The launcher learned of a
  Windows server's exit through a callback queued to the .NET thread pool, so under load it could
  arrive seconds after the server had exited. A server that exited before readiness then failed
  its start as one that closed its stdout, without its exit code; OpenCodeServer.Exited
  completed late; and ending a server that had already exited could still end the descendants it
  left running. The exit is now observed on the operating system's own wait thread, as libuv
  observes it, so each of these reads the exit as soon as the kernel reports it.
• OpenCodeServer.EnsureAsync started through a .cmd or .bat shim on Windows opens no
  console window. With a batch shim such as npm's opencode.cmd as the command, the background
  service took a new console of its own, with a visible terminal window that took the focus and
  stayed open for the service's life, and its startup output went to that window instead of to
  the SDK. The shim now starts with a console that has no window, which the service inherits, so
  its window stays hidden and its startup output reaches the SDK again. A service started from an
  .exe still starts detached, with no console.
• On Unix under Mono, a failed chmod of an owner-only file fails its write. The
  netstandard2.0 and net472 assets set mode 0600 on the files discovery and EnsureAsync
  write through a chmod child process after the create. That process now receives a quoted path,
  and a nonzero exit removes the file and fails the create, as the modern targets' atomic
  owner-only create does. Behaviour change: such a file was kept at the process umask before.

📋 Important Notes

• This release is built on the .NET 11 release-candidate SDK. A preview package may build on a
  go-live release candidate (ADR-0002); the first non-preview package waits for the GA SDK. The
  net11.0 asset needs the .NET 11 runtime, and a net10.0 app keeps using the net10.0 asset.
• From 1.0.0, a minor version may move the protocol pin and change the generated surface the
  way upstream changed it, each change listed under protocol changes; only a major version breaks
  the hand-written design (ADR-0034).