Swarm — many agents, one command

What a swarm is

A swarm is many agent microVMs doing the same kind of work at once. You bring up N agents with one command, send the whole cohort a task with one command, and pull back every result with one command — then pay for exactly the minutes they ran, out of a prepaid credit balance.

It runs on the Spot usage tier: half-price, interruption-tolerant compute — the right economics for a burst of short-lived agents that all finish and go away.

The shape is always three phases: Setup → Dispatch → Collect.

1. Setup — prepay, then fan out

Top up credits (your card is never charged until you do), then bring up the swarm. --count N fans out N Spot agents in one call, and --group saves them as a named cohort so every later command can drive them as one:

jurniti credits buy 20
jurniti up --tier spot --harness hermes --count 50 --group demo

Watch them come up in a second terminal:

watch jurniti vms ls

2. Give the swarm its key (auth at scale)

Each hermes agent reaches a model through one OpenRouter key. Write it to every agent in the group with a single command — this is BYOK, so the key lands encrypted inside your VMs, is never stored in our database, and is never echoed back to your terminal:

jurniti env set --group demo --no-restart OPENROUTER_API_KEY=sk-or-...

3. Dispatch — one task, the whole swarm

jurniti run hands a task (a prompt) to an agent. The platform builds and runs the agent's headless command for you — you send a task, never a script — and each agent writes its answer to /work/out.txt. With --group, the task goes to every agent in the cohort concurrently, so the swarm's wall-clock is the slowest single agent, not the sum:

jurniti run --group demo "Write a punchy one-line launch headline for a developer tool."

It reports how many agents succeeded and how many failed.

Give each agent a different task (templating)

A swarm is most useful when every agent does varied work, not 50 copies of one prompt. Put a {placeholder} in the task and fill it per-agent with --var:

jurniti run --group demo \
  --var audience=developers,designers,founders,marketers \
  "Write a punchy one-line launch headline for a {audience} tool."

Each agent gets its own prompt — one per value, mapped across the swarm in the group's stable order. Rules:

• --var KEY=v1,v2,… provides the values; repeat --var for more placeholders (all lists must be the same length, zipped one row per agent).
• --var KEY=@file.txt reads one value per line — the easy way to feed 50 distinct values to 50 agents (an "array" from a file).
• Fewer values than agents cycle (3 audiences across 9 agents = 3 each); more values than agents is an error (surfaces the mismatch).
• Built-in tokens need no --var: {index} (0-based), {n} (swarm size), {vm} (the agent's id). So "Summarize shard {index} of {n}." just works.
• A misspelled {placeholder} fails before anything dispatches (no agent runs a half-filled prompt). Write {{ / }} for literal braces.

4. Collect — every result, one folder

jurniti cp copies a file out of your VMs. With --group it fans the whole swarm's output into a local directory, one file per agent:

jurniti cp --group demo /work/out.txt ./out

Now ./out/ holds one file per agent (<agent-id>-out.txt) — the entire swarm's work, collected.

5. The receipt

The meter only ran while the agents did. See exactly what the burst cost:

jurniti credits history

The whole thing

jurniti credits buy 20
jurniti up --tier spot --harness hermes --count 50 --group demo
jurniti env set --group demo --no-restart OPENROUTER_API_KEY=sk-or-...
jurniti run --group demo "Write a punchy one-line launch headline for a developer tool."
jurniti cp --group demo /work/out.txt ./out
jurniti credits history

Fifty agents, one task each, every result on your disk — and a receipt.