Adds harness-core::config::markdown to parse SKILL.md frontmatter/body, a skill tool in harness-tools to invoke them, and system-prompt wiring so available skills are advertised to the model. Includes the rustfmt pass over the M5 files touched by this and the preceding LSP/rmcp work.
Adds the DiagnosticsSource seam trait in harness-core::lsp (kept out of harness-tools so tools never link the LSP crate directly), and implements it in harness-lsp as a pool that lazily spawns one language server per file extension (rust-analyzer, typescript-language-server, gopls, pyright-langserver) only when the binary is on PATH. Adds harness-tools::diagnostics and wires diagnostics into edit/write/bash/glob/grep output.
Adds a dedicated provider entry for opencode's Zen proxy on top of the existing OpenAI-compatible codec, with its own config wiring in harness-app and harness-core::config::load.
Adds the jobs pane to the TUI with a new snapshot test, subtask drill-in navigation, and periodic reminders injected into the engine loop for long-running background jobs.
Lets subagents report context files back to the job board (surfaced from the read tool) so the parent session's next-turn context includes what a background child has been looking at.
Adds the task tool and subagent spawner in harness-tools, and wires spawning/aliasing/reuse and depth limits through harness-app and the job board, so an orchestrator session can launch and track child sessions.
Adds harness-core::engine::jobs, the JobBoard tracking foreground/background subagent jobs with persistence, plus permission-rule intersection so a spawned subagent's effective permissions are the parent's rules narrowed by its own.
Extends the model catalog with per-token pricing and accumulates cost per engine step, threading the running total through the store and up into harness-app so it can be surfaced in the UI.
Adds the Anthropic SSE codec (codec/anthropic.rs) translating Anthropic's event stream into LlmEvents, the AnthropicProvider, and registry wiring so the engine loop can run against the real API instead of just MockProvider.
Implements the first five harness-tools: read, write, bash (with timeout/output truncation), glob, and grep, plus shared path-resolution helpers. Wires them into the core tool registry and processor.
Adds the Tool trait, config loading/schema, the Provider trait plus an Llm event surface, a permission service, and the core engine loop with a doom-loop guard and retry scaffolding. The processor drives a text/tool-call/final-text turn against a Provider, laying the groundwork for the MockProvider integration test and the real Anthropic path.
Sets up the Cargo workspace (harness-core, harness-tools, harness-providers, harness-mcp, harness-lsp, harness-app, harness-tui) and the ten architecture docs under docs/. harness-core gets its foundational types (session/message/part/model ids), an in-process event bus, a table-driven permission evaluate function, and a SQLite-backed storage actor with schema and roundtrip coverage. Every crate compiles empty and a bin stub prints its version.
darman