Glossary
spore.host's names are deliberately close (spore, spawn, spored, spore-bot), which makes the family cohere but can blur which word means what. This page fixes the vocabulary.
The canonical noun
instance — the canonical word for a machine spore.host manages. When you need to disambiguate from a raw EC2 instance you launched some other way, say spore.host-managed instance (or managed instance). Prefer "instance" throughout; avoid using "spore" as a noun for a machine.
Tools
| Term | What it is |
|---|---|
| spore.host | The project and the toolkit as a whole. Also the domain. Not a hosted service — see Security, credentials & data flow. |
| truffle | The discovery CLI: find instance types, compare prices, check quotas. Read-only. |
| spawn | The launcher CLI: launches instances and provisions spored onto them; manages their lifecycle from your laptop. |
| spored | The lifecycle daemon that runs on each launched instance and enforces its rules from the inside. You never install it — spawn provisions it. |
| spore-bot | The Slack/Teams integration for controlling instances from chat. |
| lagotto | The capacity watcher: waits for scarce capacity and notifies or launches when it appears. |
| spore-host-mcp | The MCP server exposing truffle and spawn to AI assistants. |
Lifecycle concepts
| Term | Definition |
|---|---|
| TTL (time to live) | The absolute deadline, set once at launch, at which the instance terminates. It never resets across stop/wake cycles; only spawn extend moves it, and only forward. The hard backstop. See Costs & safety guarantees. |
| idle timeout | A soft rule: stop or hibernate after a period with no activity. Any activity resets it. Idle never terminates — it only stops/hibernates. Not the same as the TTL. |
| completion signal | An explicit "my work is done" marker — a sentinel file (default /tmp/SPAWN_COMPLETE) or spored complete. Triggers the configured on-complete action. |
| completion sentinel | The file spored watches for the completion signal. Its appearance — not your command merely finishing — is what triggers the action. |
| pre-stop hook | A shell command spored runs before any lifecycle-triggered stop or terminate, to save work (e.g. aws s3 sync /results s3://…). |
| cost limit | An optional compute spend ceiling (instance rate × total compute time, carried across stop/resume); spored terminates when it's crossed. Independent of the TTL — first ceiling to fire wins. |
| reaper | The out-of-band backstop that terminates managed instances past their TTL even if spored is unhealthy. See Costs & safety guarantees. |
Compute-shape concepts
| Term | Definition |
|---|---|
| job array | A group of related instances launched and managed together. See Job arrays. |
| parameter sweep | Running the same job across many parameter combinations in parallel. See Parameter sweeps. |
| MPI cluster | Multiple tightly-coupled nodes launched together for distributed workloads. See MPI clusters. |
| Capacity Block for ML | A pre-purchased, time-boxed reservation of scarce GPU capacity. Launch into it at its start time with lagotto launch --at. See Lagotto. |
| watch | A Lagotto request to wait for capacity for a given instance type and act (notify/spawn/hold) when it appears. |
Common confusions
For the pitfalls these terms cause — TTL vs idle timeout, find vs search, region vs AZ, quota vs actual capacity, stop vs hibernate vs terminate, a command finishing vs the completion sentinel appearing — see Troubleshooting & common mistakes.