A2a Cursor Runbook

a2a + Cursor Agent CLI — discovery & bootstrap runbook

Who this is for: you have the a2a-skill repo and want to spawn a Cursor Agent peer via a2a-spawn --cli cursor. Unlike debri (which wraps Devin through tmux), no custom harness is required — the official agent / cursor-agent binary already exposes automation flags.

Step 0 — Prerequisites

command -v agent || command -v cursor-agent || echo "MISSING: Cursor Agent CLI"
command -v a2a || echo "MISSING: a2a (run ./install.sh from a2a-skill)"

Step 1 — Install and authenticate Cursor Agent CLI

Install via Cursor’s documented Agent CLI install (typically lands as ~/.local/bin/agent and ~/.local/bin/cursor-agent symlinks). Then:

agent login          # or: CURSOR_API_KEY=... for non-interactive auth
agent status         # must show logged in
agent --version

Headless smoke (no a2a yet):

agent -p --trust --mode ask "Reply with exactly: ok"

Step 2 — Point a2a-spawn at the binary

a2a-spawn's cursor branch resolves in this order:

1. $CURSOR_AGENT_BIN env var (if set and executable)
2. ~/.local/bin/agent
3. ~/.local/bin/cursor-agent
4. agent or cursor-agent on PATH

Override only if needed:

export CURSOR_AGENT_BIN=/path/to/cursor-agent
# optional: pin workspace for the agent process
export CURSOR_WORKSPACE=/path/to/workdir

CLI aliases accepted by a2a-spawn: cursor, agent, cursor-agent.

Step 3 — Get a2a-skill onto PATH (if needed)

git clone https://github.com/javimosch/a2a-skill.git
cd a2a-skill
./install.sh
a2a version

Step 4 — Smoke test: one cursor agent, solo

PROJECT=cursor-smoke
export A2A_PROJECT=$PROJECT
a2a clear --yes 2>/dev/null; a2a init
a2a register solo --role dev --cli cursor

cat > /tmp/cursor-smoke.kit <<EOF
You are agent "solo" on an a2a peer bus, project $PROJECT.
Do EXACTLY this, then stop:
1. Run: a2a status active --as solo
2. Write the word "hello" to /tmp/cursor-smoke-output.txt
3. Run: a2a status done --as solo
EOF

PID=$(a2a-spawn --cli cursor --id solo --project $PROJECT \
    --log /tmp/cursor-smoke.log --kit-file /tmp/cursor-smoke.kit)
a2a register solo --pid "$PID" --upsert
echo "spawned pid=$PID"
# wait for completion (typically 30–90s depending on model/quota)
for i in $(seq 1 60); do
  st=$(A2A_PROJECT=$PROJECT a2a list --json 2>/dev/null | grep -o '"status": "[^"]*"' | head -1)
  echo "t=${i}0s $st"
  echo "$st" | grep -q done && break
  sleep 10
done
A2A_PROJECT=$PROJECT a2a list --json
cat /tmp/cursor-smoke-output.txt

Expect:

• a2a list shows solo with status: "done"
• /tmp/cursor-smoke-output.txt contains hello
• /tmp/cursor-smoke.log has stream-json events from agent -p

If it stalls, check the log for trust/auth/quota errors. Free-tier limits can delay or fail runs — retry or set --model to an available model from agent models.

Step 5 — Join a real a2a team

Same Pattern 3 protocol as other CLIs (--cli cursor). Watchdog/lease apply unchanged.

Cursor-specific pitfalls

Why not a ~/ai/debri-style wrapper?

debri exists because Devin needs fresh tmux sessions, TUI stripping, and structured JSONL. Cursor Agent CLI already provides -p, --output-format stream-json|json, --trust, --force, and --workspace. Wire it in a2a-spawn directly.

rbm21

For Cursor Agent CLI on the rbm21 LXC (install, auth sync, a2a smoke), use the global skill rbm21-cursor at ~/.agents/skills/rbm21-cursor/ on the workstation (scripts: sync-auth.sh, install-agent.sh, smoke-a2a.sh).

References

• Cursor Agent CLI: agent --help / agent about
• Auth docs: https://cursor.com/docs/cli/reference/authentication
• a2a main skill: .agents/skills/a2a/SKILL.md
• debri runbook (contrast): .agents/skills/a2a-debri-runbook/SKILL.md