# Kolu > Drive one AI agent from another through kolu's terminals: spawn a Claude Code / Codex / opencode session in a PTY, prompt it, watch the screen for its reply, read it, and prompt again — a create→send→snapshot loop run with the `kaval-tui` CLI directly (no MCP). `kaval-tui` writes input, reads scrollback, and provides a hook-free done-signal (`wait --until idle:` on raw PTY output); `pulam-tui` adds a precise agent-state done-signal when you drive hooked terminals. Triggers on "drive another agent", "send a prompt to a terminal agent", "have one agent prompt another", "agent drives agent", "orchestrate agents in terminals", "make Claude drive Codex", "prompt the agent running in that terminal", or wiring a loop where one coding agent supervises another. - Skill: `srid/kolu-3` (Agent Skill) - Install (CLI): `npx skillmds@latest add srid/kolu-3` - Raw SKILL.md: https://api.skillmd.com/api/skills/srid/kolu-3/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: srid (https://skillmd.com/u/srid) - Updated: 2026-09-22 - Page: https://skillmd.com/skills/srid/kolu-3 --- # kolu — drive one agent from another through its terminal You can run a coding agent (Claude Code, Codex, opencode) inside a kolu-owned PTY and steer it from the outside: type a prompt, submit it, watch the screen until it's done, read what it said, type the next prompt. The whole toolkit is **`kaval-tui`** — write input, read the screen, spawn, kill. The driver runs it directly; there's no server to stand up and no MCP layer. For a raw `kaval-tui`-spawned terminal, the done-signal is **`kaval-tui wait --until idle:`** — it blocks in the daemon on the raw PTY output and returns the moment the agent stops streaming, with no shell hooks (below). `pulam-tui` adds a *precise agent-state* done-signal (`wait --until `), but only for **hooked** terminals (the last section); for raw terminals, reach for `kaval-tui wait`. ## The loop ```sh id=$(kaval-tui create --json -- claude | jq -r .id) # spawn the inner agent kaval-tui send "$id" "refactor the parser to use a lexer" # 1. TYPE the prompt kaval-tui send "$id" --key Enter # 2. SUBMIT it (its own step) kaval-tui wait "$id" --until idle:800 --timeout 600000 # 3. let its turn finish (below) kaval-tui snapshot "$id" --viewport # 4. read the screen kaval-tui send "$id" "now add tests for it"; kaval-tui send "$id" --key Enter # loop ``` Leaf commands, all `kaval-tui`: **create** (spawn) · **send** (type) · **send --key Enter** (submit) · **wait** (block until the turn ends) · **snapshot** (read) · **kill**. **Typing and submitting are two separate `send`s** — that is load-bearing, see below. > **Read with `snapshot --viewport`, not `| tail`.** A bare `snapshot` prints the > **whole scrollback** — thousands of lines on a long-running or compacted agent — > so `snapshot | tail -8` hands you the bottom of the buffer (often just trailing > blanks), not the live screen. `--viewport` asks the daemon for just its > terminal's last screenful — the right "what's on screen now" read, and correct > regardless of how tall your own shell is (over `--host` the remote terminal is a > different size). `--tail N` (alias `--lines N`) bounds it to the last N lines > when you want a fixed slice. ## `kaval-tui send` — type, then submit (two steps) `kaval-tui send [text...]` writes input to the terminal — **exactly the text (and any `--key`s) you pass, with NO implicit Enter**. It types; it does not submit. **Submitting a prompt is its own second `send`:** ```sh kaval-tui send "$id" "fix the failing test in parser.ts" # 1. type the prompt kaval-tui send "$id" --key Enter # 2. submit it ``` **Do this as two separate `send` commands — not `send "text" --key Enter` in one call.** The separation is load-bearing: an Enter sent in the same breath as the text races Claude Code's bracketed-paste / debounced input handling — it arrives before the pasted text has registered and is **silently dropped**, leaving the prompt staged on the `❯` line while `send` reports success. A standalone follow-up `send --key Enter` lands after the text has settled, so it actually submits. (If a turn never seems to start, this is the #1 cause — `snapshot` and look for the prompt sitting unsent on the `❯` line.) Specifics: - **Multiline prompts and piped stdin go as one bracketed paste**, so they land in the input box as a block instead of submitting line-by-line. Automatic (`--paste` / `--no-paste` force it). For a big prompt, pipe it — `cat task.md | kaval-tui send "$id"` — then `send "$id" --key Enter`. - **`--key `** (repeatable, sent after the text) is both the submit channel (`Enter`) and the control channel: `Escape`, `C-c`, `Enter`, `Up`/`Down`/`Left`/`Right`, `Tab`, `Home`, `End`, `Backspace`, `M-`. - **`--json`** → `{ id, bytes, paste, keys }` to confirm what was written. **`send` is blind** — it writes whether or not the agent is ready for input. Always pair it with `snapshot` so you don't fire a prompt into a not-yet-ready session (e.g. before the TUI has drawn its input box, or over a trust prompt). **Interrupt a runaway** before redirecting it: ```sh kaval-tui send "$id" --key Escape # stop Claude Code mid-stream kaval-tui send "$id" --key C-c # SIGINT whatever's running ``` ## The done-signal — `kaval-tui wait --until idle:` After you submit, you need to know when the turn ends. For a raw `kaval-tui`-spawned terminal there's no agent-state feed — but the daemon already sees every output byte, so **`kaval-tui wait`** blocks on that raw stream and returns the instant the agent goes quiet, with **no shell hooks** and no busy-word guessing: ```sh kaval-tui wait "$id" --until idle:800 --timeout 600000 # block until the turn ends ``` - **`--until idle:`** resolves once no output byte has arrived for `` — the agent-agnostic "turn ended / awaiting input" signal, and the common case. `800` is a good default; raise it for an agent that pauses mid-thought, lower it for a snappier loop. It works identically for `claude`/`codex`/`grok`/ `opencode` because it keys on bytes, not on any agent's rendering. - **`--until match:''`** resolves once *new* output matches — use it for a completion marker or a returned-prompt sentinel (e.g. `--until match:'\$ $'`). - **`--timeout `** caps the wait and **fails loud (exit 2)** so a wedged agent can't hang the loop. If the terminal **exits** before the condition fires, `wait` exits **3** (the agent you were driving died). Met → exit **0**. - **`--json`** → one result frame per outcome: `{ id, result, … }`, where `result` is `met`/`timeout`/`gone`/`interrupted`/`closed`. A `met` frame adds `fired` (`idle`/`match`), `elapsedMs`, and `matchedLine` on a match — so a driver reads the structured `result`, never just the exit code. Quiescence ≠ "the reply is correct": idle fires whether the agent **finished** or is **blocked asking you something** (both mean "your move"). So after `wait` returns, **`snapshot --viewport` and read** what's on screen before responding. > **Fallback — screen-settle polling (only for an old daemon).** If you're > driving a kaval that predates `wait` (it errors "unhandled command"), fall back > to polling `snapshot --viewport` until the screen holds still across two reads, > capped by a deadline. It's coarser and laggier (a busy agent that pauses > mid-thought can read as settled, and the poll lags the real settle), so prefer > `kaval-tui wait` whenever the daemon has it. > > ```sh > wait_until_settled() { # fallback only — kaval-tui wait is preferred > local id=$1 deadline=$(( $(date +%s) + 600 )) prev="" cur stable=0 > while [ "$stable" -lt 2 ] && [ "$(date +%s)" -lt "$deadline" ]; do > sleep 3 > cur=$(kaval-tui snapshot "$id" --viewport) # the live screen, not full scrollback > if [ "$cur" = "$prev" ]; then stable=$((stable + 1)); else stable=0; fi > prev=$cur > done > } > ``` ## `pulam-tui wait` vs `kaval-tui wait` — two done-signals They are not rivals; they read different things: - **`kaval-tui wait`** keys on **raw output quiescence/match** — works on **any** terminal, **no hooks**. This is the one to reach for when driving a raw `kaval-tui create` agent (above). It can't tell "finished" from "blocked asking you" — both are quiescence — so read the snapshot after. - **`pulam-tui wait`** keys on **agent-state buckets** (working/awaiting/waiting) — more precise (it *distinguishes* awaiting-you from finished), but only on **hooked** terminals. Use it when you're driving terminals a kolu-server spawned (below). ### `pulam-tui wait` — the precise done-signal (hooked terminals only) When you *do* have agent-state detection, `pulam-tui wait --until ` is the exact done-signal — it blocks until the agent reaches a coarse state, then exits 0: - **`working`** — busy (`thinking` / `tool_use` / background task). - **`awaiting`** — `awaiting_user`: it's **asking you** a question. - **`waiting`** — the **just-finished** post-turn lull. `awaiting` and `waiting` both mean "your move", so `--until awaiting,waiting` catches a turn ending; `--timeout ` fails loud (exit 2) so a wedged agent can't hang the loop; if the terminal **exits** before reaching the state, `wait` fails loud too (exit 3 — the agent you were driving died); `--json` → `{ id, agent }`. > **Mind the stale-state race — wait in two phases.** `wait` matches the agent's > state **the instant it connects**, replaying whatever it is right now. So right > after a `send`, the agent may still report the *previous* turn's > `waiting`/`awaiting` for a beat before it picks up the new prompt — and a lone > `wait --until awaiting,waiting` would return immediately on that stale state, > before the turn you asked for has even begun. For a robust loop, wait for the > pickup first, then the turn-end: > > ```sh > kaval-tui send "$id" "fix the parser"; kaval-tui send "$id" --key Enter > pulam-tui wait "$id" --until working # 1. it picked up the prompt > pulam-tui wait "$id" --until awaiting,waiting # 2. its turn ended > ``` > **Caveat — agent state needs HOOKED terminals.** Detection keys on kolu's shell > rc-hooks (the OSC marks a terminal emits as commands run). `kaval-tui create` > is the **raw** multiplexer — a plain `$SHELL`, no hooks by design — so an agent > you spawn that way often isn't detected, and `wait` will just time out. `wait` > is reliable when you drive **already-hooked** terminals: the ones a running > **kolu-server** spawned (point `kaval-tui --socket $XDG_RUNTIME_DIR/kolu/pty-host.sock` > at them), or a future `kolu-tui`. For a raw `kaval-tui create` loop, use > **`kaval-tui wait --until idle:`** above — it needs no hooks. ## Reach — which daemon you're driving Bare `kaval-tui` **autodiscovers** a running daemon on this machine. Two ways to point it elsewhere: - **`--socket `** targets a specific local daemon — e.g. a running **kolu-server's** kaval (`$XDG_RUNTIME_DIR/kolu/pty-host.sock`), to drive the terminals you have open in kolu (these ARE hooked, so `pulam-tui wait` works against them once a `pulam` reads that kaval). - **`--host `** reaches a daemon on another machine (provisioned with Nix); a remote PTY survives the link. ## Acceptance Before calling a driven turn done: - You **submitted with a separate `send --key Enter`** (not an implicit Enter, not `send "text" --key Enter` in one call) — a prompt left staged on the `❯` line is the #1 failure here. - The inner agent's **reply is actually in the `snapshot`** — not an empty box or a half-rendered stream. `wait --until idle` means "output stopped", not "the answer is right"; verify the content. - Your wait had a **`--timeout`** (or deadline) so a wedged agent fails loud (exit 2) instead of hanging the loop. - If the screen settled on a **question** (the agent is awaiting you), you **read it and answered** — you didn't send the next task on top of a blocked prompt.