Herdr Orchestration

herdr Orchestration

The top-level agent is the controller (Codex, Claude, Fable, or another); it delegates to worker TUIs that gather evidence, draft bounded patches, run tests, and report. The controller owns assignment, state, conflict control, verification, integration, and the final user-facing answer. herdr is the substrate: panes host the worker TUIs, and the socket CLI (herdr …) gives the controller placement, input, screen reads, and native agent-status waits.

Workers are TUIs — no headless runners

A worker is an interactive TUI — claude or codex — launched in a herdr pane with herdr agent start. The whole orchestration loop hangs on this: herdr's agent-state integrations hook the interactive TUIs, so wait agent-status, agent list, and blocked/done detection exist only while a real TUI is on screen.

Headless runners — compozy exec, claude -p, codex exec, anything that streams JSON events into a pane — are not workers. They never report state, wait agent-status never fires, and the delegation dies silently. Recognize the failure on sight: a worker pane must show the TUI banner and input box; a pane filling with raw JSON event lines is a broken delegation — interrupt it (rtk herdr pane send-keys <pane_id> ctrl+c) and relaunch the worker with herdr agent start.

Invariants

• Scope every action to the caller workspace unless the user names another target.
• Resolve caller context from HERDR_WORKSPACE_ID, HERDR_TAB_ID, HERDR_PANE_ID, and HERDR_SOCKET_PATH (injected into every herdr pane) before any focused-window fallback.
• Address panes by explicit ids (w2:p3 — workspace-qualified) captured from command JSON output, never by guessed position.
• Pass --no-focus on every creating verb (agent start, pane split, tab create, workspace create, worktree create); use focus verbs only when the user asks.
• Retire every worker you launch: once its report is verified and its disposition recorded, close its pane (see Retire workers).

Preflight

Inspect the daemon, integrations, and caller context:

rtk herdr status                 # server running + socket path
rtk herdr integration status     # claude and codex must show `current`
rtk herdr pane current           # caller pane / tab / workspace ids
rtk herdr agent list             # agents already running

integration status must show claude and codex installed — that is what makes agent status authoritative instead of screen-scraped. If either is missing, run rtk herdr integration install claude / … install codex before launching workers.

Launch workers

Two default profiles — Claude Code on opus (claude-opus) and Codex on gpt-5.5 (codex-gpt-5.5). agent start creates the pane, runs the TUI argv directly, and returns the worker's pane_id in JSON — capture it in the registry:

rtk herdr agent start claude-opus --workspace "$HERDR_WORKSPACE_ID" \
  --cwd "$PWD" --split right --no-focus -- \
  claude --dangerously-skip-permissions --model opus "<packet>"

rtk herdr agent start codex-gpt-5.5 --workspace "$HERDR_WORKSPACE_ID" \
  --cwd "$PWD" --split right --no-focus -- \
  codex --yolo -m gpt-5.5 -C "$PWD"

Claude always launches with --dangerously-skip-permissions and Codex with --yolo — workers run unattended and must not stall on permission prompts. Plan-first runs add Claude's --permission-mode plan — the flags compose (see Plan-first delegation).

A launch is confirmed only when rtk herdr pane read <pane_id> --source visible shows the TUI banner and input box, and rtk herdr agent list shows the worker leaving unknown. A pane scrolling text while its status stays unknown is the headless-runner failure above — interrupt and relaunch.

Sending prompts to running TUIs

Prefer passing the initial prompt as the launch argv (shown above) — the session starts working immediately and skips the TUI-ready race. Exception: Codex plan-first launches bare (see Plan-first delegation).

For any follow-up to a running TUI, use pane run — it types the text and presses Enter atomically:

rtk herdr pane run <pane_id> "<follow-up prompt>"

A trailing \n inside send-text does not submit — a TUI renders it as a soft newline and the prompt sits unsubmitted. When a prompt must be staged and submitted separately, pair the text with an explicit key:

rtk herdr pane send-text <pane_id> "<prompt>"
rtk herdr pane send-keys <pane_id> enter

Confirm delivery with rtk herdr pane read <pane_id> --source visible (input line empty, working indicator active) or rtk herdr wait agent-status <pane_id> --status working --timeout 15000. An unconfirmed send is not delivered.

Plan-first delegation (opt-in)

Plan-first runs only when the user activates it — an explicit ask ("plan first", "plan mode") or a --plan-mode flag on the invocation. The default delegation is direct: launch and run hands-off. For investigation-heavy slices (root-cause fixes, multi-file or cross-package changes, unfamiliar code), offer plan-first and let the user decide — never switch a worker into plan mode without that signal.

Once activated, the worker plans, the controller reviews and accepts, then it runs hands-off. The launch flags, shift+tab sequences, status checks, and acceptance menus are exact and differ per TUI. Read references/plan-mode.md in full before launching a plan-first worker.

Delegation packets

Send each worker prompt as a standalone contract. Include:

• repo path and exact objective
• worker role and model
• execution mode: direct (default) or plan-first (user-activated)
• files, packages, or surfaces in scope
• files and behaviors explicitly out of scope
• claimed files or work slice, to avoid conflicts
• expected evidence: files, line refs, commands, diffs, failures, screenshots, and stated uncertainty
• verification commands or browser flows to run
• stop conditions: unexpected code shape, repeated command failure, auth/model blocker, or need for out-of-scope edits

Prefer small, independent slices. Assign overlapping file claims only when the controller will integrate and resolve conflicts immediately.

Worktree isolation

When workers must edit overlapping files in parallel, give each an isolated worktree and point the worker's --cwd at it — herdr manages worktrees natively:

rtk herdr worktree create --workspace "$HERDR_WORKSPACE_ID" \
  --branch <slug> --no-focus --json

Track workers

Orchestrations are long-running — worker slices take minutes to hours, and a worker is never abandoned because a wait expired. Block on herdr's native agent status in check-in intervals of 3–5 minutes (sized to the slice — longer for heavier slices) instead of polling screens:

rtk herdr wait agent-status <pane_id> --status done --timeout 300000     # completion check-in
rtk herdr wait agent-status <pane_id> --status blocked --timeout 300000  # question or menu
rtk herdr wait output <pane_id> --match "<text>" --timeout 300000        # specific screen string

--timeout is the check-in interval, never a deadline on the worker. On expiry (exit 1, timed out waiting for agent status change), read the screen (rtk herdr pane read <pane_id> --source recent --lines 120) and re-enter the wait — loop until the worker reaches a terminal state, asks a question, or a stop condition fires. When a reported status looks wrong, debug detection with rtk herdr agent explain <pane_id> --json.

Maintain a compact registry in the task ledger or handoff: controller identity; worker name, role, model; workspace/tab/pane ids; objective sent and start time; status (starting, planning, plan-review, plan-accepted, running, blocked, reported, verified, retired); claimed files or work slice; worker-reported commands and results; controller verification performed; final disposition (accepted, rejected, superseded, or blocked).

Label worker panes so the herd stays legible, and announce milestones without stealing focus:

rtk herdr pane rename <pane_id> "claude-opus: fix loops"
rtk herdr notification show "Workers done" --body "2/2 verified" --sound done

Verify worker output

Treat worker output as untrusted until verified. Monitor and verify without changing focus:

• Read worker panes read-only (pane read --source recent --lines 200); ask a worker for a concise status summary when output is unclear.
• Re-open cited files locally to verify high-impact findings.
• Re-run claimed test results with fresh controller commands when the result gates completion.
• Review the final diff before accepting any worker patch.
• If a worker edits outside its claim, pause integration and decide: accept, request user-approved cleanup, or supersede with controller edits.

Retire workers

A delegation ends with the worker retired — pane closed — not just its report read. Retire each worker the moment its disposition is recorded and no follow-up prompt is planned, as part of handling that worker's completion, never deferred to an end-of-run sweep:

rtk herdr pane close <pane_id>

Closing the pane ends the TUI session and its scrollback, so record what the registry needs first — report text, cited line refs, command output. Files, diffs, and worktrees survive on disk.

A worker stays open only while mid-run or blocked, while its screen is evidence for an unresolved failure, or when the user asks to inspect it — record the reason in the registry. The orchestration is complete only when rtk herdr agent list shows none of this controller's workers still running: every worker retired, or its open pane justified in the registry.

Stop conditions

Stop and report instead of improvising when:

• herdr rejects a valid workspace, tab, or pane ref, or rtk herdr status shows no running server.
• a worker TUI rejects the model alias, auth state, working directory, or a startup flag — report the exact blocker, and get user approval before downgrading a model or switching tools.
• authentication blocks the TUI.
• a worker's status stays unknown while output scrolls and agent explain shows no matched rule — detection is broken or the pane is running a headless process.
• a plan-mode status line or acceptance menu cannot be confirmed via pane read or wait output, or a worker's plan stays out of scope after a re-planning round.
• workers need overlapping edits the controller cannot integrate safely.
• a task needs focus-changing herdr verbs the user has not approved.