Runtime reference
Exo#
Exo is a recursive self-improving harness whose state directory is workspace-relative rather than home-anchored — the only runtime in the matrix that works that way, which is why discovery scans instead of resolving a single path.
| Runtime id | exo |
| Category | Self-improving agent harness |
| Vendor | Exo Harness |
| Tier | Paid tier (Starter and up) |
| Upstream | github.com/exoharness/exo |
Where the data comes from#
ClawMetry reads these locations, in order, and never writes to any of them.
<workspace>/.exo/exoharness/agents/<agent-uuid7>/record.json<workspace>/.exo/exoharness/agents/<id>/conversations/<conv-uuid7>/events/<event-uuid7>.json
Format. One pretty-printed JSON file per event. Filenames are UUIDv7, so lexical order is chronological order.
Environment variables#
| Variable | Effect |
|---|---|
CLAWMETRY_EXO_ROOTS | path-separated workspaces or .exo dirs to scan |
See Environment variables for the variables that apply to every runtime.
Tokens and cost#
Tokens. On the usage record attached to a messages event, with the full split.
Cost. Straight from Exo's own usage.cost_usd, computed at call time. When Exo's price-table fetch failed, tokens persist without cost and ClawMetry marks the session partial or tokens_only.
Why this section exists
Runtimes differ enormously in what they persist. Rather than showing a plausible number everywhere, ClawMetry reports what the store actually contains and marks the rest unknown. A cost of $0.00 and a cost of unknown mean different things, and the dashboard keeps them different.
Sub-agents and delegation#
thread_forked events carry fork lineage.
Things worth knowing#
- A ClawMetry session is the Exo conversation, because that is the durable unit that owns the event log. Exo's own
session_idfield is a sub-conversation marker and is not surfaced. - Discovery results are TTL-cached so a page load does not rescan your disk.
Verify it is being read#
# Is this runtime detected, and would this install unlock it?
clawmetry runtimes --json | jq '.runtimes[] | select(.id=="exo")'
# Why is it locked, if it is?
clawmetry runtimes --why exo
# Any sessions ingested yet?
curl -s 'http://localhost:8900/api/local/sessions?limit=5' \
| jq '.rows[] | {session_id, agent_id, events, cost_usd}'If detection succeeds but no sessions appear, work through Troubleshooting — the usual causes are a relocated data directory (set the override above), a session limit that is hiding older runs, or a runtime that simply has not written anything yet.