I booted DeepSeek Harness with a single npx command and no API key, dumped its 145-row boot tree with --dump-config, and edited the patch layer by hand. The web profile ships with every model-facing tool switched off, and the reason turns out to be interesting. I also walked straight into the trap where patching a row config silently kills a CLI flag.
DeepSeek Harness (dsh) turns the model adapter, the tool registry, the session log, and even the agent loop into Cordis plugins, then assembles the product by stacking patch layers on top of an empty tree. Two weeks after release it passed 200k GitHub stars. This is a source-level analysis of its kernel (Cordis), profile and bundle composition, the rule that the session log is the source of truth, capability seams, self-modification tools, and the way it runs Claude Code and Codex as subagents.
Cline is a coding agent that lets you approve every action inside VS Code and roll back at any time. It also detaches its core from the host via a protobuf/gRPC boundary (ProtoBus + HostBridge), so the same core runs in the editor and in a terminal CLI. We analyze Plan/Act approval, checkpoints, and the host abstraction, contrasting them with OpenCode's headless engine.
OpenCode externalizes model metadata to models.dev and even hand-rolls its own LLM protocol layer, so any provider attaches with a single line of data. A single Effect-based HTTP engine is shared by the TUI, web, desktop, Slack, and editors (ACP), while two generations — legacy and V2 — coexist. We analyze the structure against Qwen Code's single-vendor platform.
CodeGraph is a TypeScript tool that uses tree-sitter to parse source code, builds a local SQLite knowledge graph of symbols, edges, and files (with FTS5), and exposes that graph via an MCP server to coding agents like Claude Code, Cursor, Codex, and Hermes Agent. Instead of burning tokens navigating a codebase with grep/Read calls, agents get answers from a single codegraph_explore invocation. This post analyzes the architecture that makes that possible.
OpenHands productizes an AI coding agent across a local GUI, FastAPI app server, sandbox, agent-server, SDK, event store, MCP, and skill system. This analysis focuses on the boundary between the app server and GUI that the current OpenHands repository is responsible for.
Qwen Code is a TypeScript-based coding agent that bundles a terminal CLI, an LLM provider abstraction, a tool scheduler, MCP, Skills, Subagents, the qwen serve daemon, channel plugins, and IDE integration into a single repository. We analyze how it reconstructs a Claude Code-style experience on top of Qwen/DashScope, multiple providers, and an extensible agent runtime.