CodexSharpSDK

ManagedCode.CodexSharpSDK

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`ManagedCode.CodexSharpSDK` is an open-source .NET SDK for driving the Codex CLI from C#.

It is a CLI-first `.NET 10 / C# 14` SDK aligned with real `codex` runtime behavior, with:

• thread-based API (start / resume)
• streamed JSONL events
• structured output schema support
• image attachments
• --config flattening to TOML
• NativeAOT-friendly implementation and tests on TUnit

All consumer usage examples are documented in this README; this repository intentionally does not keep standalone sample projects.

Installation

dotnet add package ManagedCode.CodexSharpSDK

Prerequisites

Before using this SDK, you must have:

• codex CLI installed and available in PATH
• an already authenticated Codex session (codex login)

Quick check:

codex --version
codex login

Quickstart

using ManagedCode.CodexSharpSDK;

using var client = new CodexClient();

var thread = client.StartThread(new ThreadOptions
{
    Model = CodexModels.Gpt54,
    ModelReasoningEffort = ModelReasoningEffort.Medium,
});

var turn = await thread.RunAsync("Diagnose failing tests and propose a fix");

Console.WriteLine(turn.FinalRe