---
title: using-system-snapshot skill design
type: concept
updated: 2026-06-09
---

# using-system-snapshot skill design

New policy+technique skill (v0.1.0) wrapping the single MCP call
`mcp__projects-meta__meta_system_snapshot`. Replaces the old scatter of
`tasklist` + `docker ps` + a manual `meta_status` read with one round-trip for
session-start ops orientation.

## Why a skill

The failure mode it guards: an agent asserts "the poller is running" / "all
containers are up" / "you have N active tasks" from memory or a stale earlier
snapshot, without re-checking. The skill makes the rule explicit — **no claim
about poller / local-docker / task-load state without calling the tool in the
current turn**. Mirrors the read-only, no-grant posture of [[using-vds-ops]].

## Tool output shape (verified live 2026-06-09)

Three keys:

- `poller`: `{ running: bool, projects: "<owner/repo …>" }` — **live**.
- `docker`: `[{ name, status }]` — **local** machine containers (includes
  `agents-task-runner-*`), NOT the VDS. Status strings like `Up 4 hours`,
  `Up 26 hours (healthy)`; problems show as `Restarting` / `Exited` /
  `(unhealthy)` / `Created` / `Paused`. **live**.
- `tasks`: `{ "<owner>/<repo>": { active, blocked } }` — **from the
  projects-meta cache**, so approximate.

## Design decisions

- **Output = three lines, one per section** (per task spec). Docker line reports
  `N/N up` when all healthy, else lists only the bad containers; tasks line gives
  Σ active / Σ blocked + the busiest 2–3 projects. Never dump raw JSON.
- **Liveness split made explicit.** Poller + docker are read at call time; task
  counts come from the cache. The skill tells the agent to flag task-count
  staleness and defer precise per-task work to [[projects-meta-skills]]
  (`using-projects-meta` Step 0 freshness gate, or local `.tasks/` on disk).
- **Scope boundaries.** Deep single-container diagnosis (logs/inspect/stats) is
  explicitly out — that's [[using-vds-ops]] for the VDS or `docker logs`
  locally. The snapshot only carries name + status.
- **Read-only, no per-session grant** — same as [[using-vds-ops]]. The tool
  takes no args; no preview/confirm dance (unlike the projects-meta mutations).

## Prerequisites

Needs `mcp__projects-meta__meta_system_snapshot` (shipped by `projects-meta-mcp`;
the `meta-system-snapshot` capability lives in `OpeItcLoc03/common`). If the tool
is absent, the server isn't registered → `setup-projects-meta`.

## TDD note

Markdown policy artifact — no code/test surface (consistent with sibling skill
tasks). Behavioral trigger smoke-test is the paired `skill-using-system-snapshot-review`
task, not this implementation task.