# Append Letters

> Demo orchestrator that appends characters to a file by running two child skills in sequence.

- Skill: `faesel/append-letters` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add faesel/append-letters`
- Raw SKILL.md: https://api.skillmd.com/api/skills/faesel/append-letters/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: faesel (https://skillmd.com/u/faesel)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/faesel/append-letters

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# append-letters

**When to use this skill**

- A minimal, readable example of a GridWatch **sequential** orchestrator.
- Runs `append-x` then `append-y`, each appending one character to a shared file.

Everything above this line is yours to edit. The block below is generated by GridWatch from the
orchestration configuration in `gridwatch.json` — edit the configuration in the Skills Graph and
click **Save** to regenerate it, rather than editing between the markers by hand.

<!-- ============================================================ -->
<!-- GRIDWATCH-MANAGED — DO NOT EDIT BELOW.                       -->
<!-- This block is regenerated from the Skills Graph orchestration -->
<!-- config. Manual edits here are overwritten on regenerate.      -->
<!-- ============================================================ -->
<!-- gridwatch:orchestration:start -->

## Workflow (sequential)

1. **Announce** — Print: `🚀 [append-letters] Starting append-letters (sequential)...`
2. **Determine the session identifier** — Set `SESSION_ID` to the current Copilot CLI session id (the UUID of the active session under `~/.copilot/session-state/`). Use it to name all output files so concurrent runs do not clash.
3. **Run each step in order, waiting for each to finish before the next. Announce each step yourself before running it:**
   1. **append-x** — Print `📣 [append-letters] Running append-x…`, then run the `append-x` skill and wait for it to finish. Instruct it to write its output to `/tmp/gridwatch-demo/letters-<SESSION_ID>.txt`.
   2. **append-y** — Print `📣 [append-letters] Running append-y…`, then run the `append-y` skill and wait for it to finish. Tell it to read its input from `/tmp/gridwatch-demo`. Instruct it to write its output to `/tmp/gridwatch-demo/letters-<SESSION_ID>.txt`.
4. **Confirm each step wrote its output** before continuing.
5. **Report back** — Print a short summary and the absolute path(s) to the output(s).
6. **Announce completion** — Print: `✅ [append-letters] Finished append-letters (sequential).`

<!-- gridwatch:orchestration:end -->
<!-- ============================================================ -->
<!-- END GRIDWATCH-MANAGED — you may edit below this line again.  -->
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## Notes

The two child skills append to the **same** file, so by the time the orchestrator finishes the
file contains `XY`. Because the run is sequential, `append-y` is guaranteed to run after
`append-x` has finished writing.