thurbox: Skill for Claude Code

Thurbox agent definitions

Working reference indexed by AGENTS.md. The rationale behind these decisions is owned by the docs under docs/; a change that invalidates what this says updates it in the same PR.

Agent Definitions

Per-agent reference + the "adding a new built-in" checklist: docs/AGENTS.md (each built-in's exact config, ID model, and status-hook mechanism, plus every file to update when promoting a CLI to a built-in).

The set of launchable coding agents is declared as data in ~/.config/thurbox/agents.toml, seeded with built-ins (claude, codex, antigravity, opencode, aider, copilot, vibe, pi, omp) plus shell on first run.

shell is the one seeded entry that is not a coding agent: the platform's own interactive shell (bash -i, or powershell -NoLogo on native Windows, where the multiplexer is psmux). The platform is the session's host: while the entry (or its inherited variant) is still a stock command/args pair, session_ops::resolve_agent_def swaps in the host's own (shell::shell_agent_def); an edited shell is launched as written. It exists so a session can be anything, and it is the ready-made form of session create --command. Because it declares no resume_args/fork_args, it also documents the rule by example: those groups are the conversation address, and an entry without them can be restarted but never resumed. A raw --command session behaves identically — thurbox builds it a synthetic AgentDef with empty arg groups and persists the recipe on the session row, since there is no agents.toml entry to re-resolve at restart. Each [[agents]] entry is an AgentDef:

default = "claude"

[[agents]]
name = "claude"
command = "claude"
args = []                               # always passed; bake a model here if you want one
resume_args = ["--resume", "{id}"]      # emitted when resuming
fork_args = ["--resume", "{id}", "--fork-session"]
new_session_args = ["--session-id", "{id}"]  # emitted on a fresh spawn
additional_dir_args = ["--add-dir", "{dir}"] # repeated per multi-repo member

[[agents]]
name = "codex"
command = "codex"
resume_args = ["resume", "{id}"]
fork_args = ["fork", "{id}"]