Your coding agents learn while you sleep
Every night hippo goes through the day's sessions from every agent you run and turns what went wrong into rules. A second model checks each one against what actually happened. Keep a rule, and tomorrow every session starts already knowing it.
install
macOS or Linux, no sudo. MIT. Other installs
Day you correct the same thing twice
-
CCCheck the gallery page and send me screenshots10:07
you
no, previews use the staging database, not production
CxTern: export pipelinequiet
-
CCCheck the gallery page and send me screenshots13:32
you
dont point previews at the production database again, staging only
DSTern: album covers in parallellive
CCGet the release branch ready to mergewaiting
CxAdd the cache cap testdone
CCShow me the export settingsquiet
36 sessions that day. hippo reads all of them.
Night 03:30, hippo goes through the day
proposed rulefrom 2 sessions
Use the staging database for previews, never production
confirmedby a second model, against turn 3 of both sessions
proposed fixAuth sessions.md
last 7 days now 24 hours
rejectednothing in the evidence shows the 24 hour lifetime was deployed … Keep 7 days until a release confirms it.
proposed fixThumbnail pipeline.md
confirmedapplied, with a receipt
This run: 10 notes checked, 4 changes, 2 rejected. Any change can be undone.
Morning you keep it, every agent starts with it
Inboxyou did not write this
Use the staging database for previews, never production
KeepEditDismiss
CxCodexhippo brief
required: notes/START HERE.md … rules: - Run previews and manual checks against the staging database (npm run preview -- --db staging), never production.
about 1.5 KB of a 25 KB budget: the notes this task needs, not the pile
DSDeepSeek Harnesssession start
required: notes/START HERE.md
Demo data from app/scripts/demo-home.sh, the synthetic home in the repo. Its sessions are all Claude Code; the Codex and DeepSeek Harness ones are drawn.
Built from what happened
A memory file holds what an agent chose to write down. hippo reads every session on the machine.
- CC
~/.claude*/projects/ - Cx
~/.codex/sessions/ - DS
~/.dsh/sessions/ - OC
~/.local/share/opencode/ - Mu
~/.local/share/muse/sessions/ - CM
~/.commandcode/projects/
5,078 sessions784,867 turns162 s to index
The maintainer's machine, into one local SQLite file.
It cannot make things up
Memory an agent writes for itself goes stale, and nothing notices. Here a second model with a fresh context must confirm every change against the evidence.
3 of 7 planted errors fixed0 of 8 correct notes damaged
the repo's eval set, with a real model7 wrong statements fixed
the maintainer's own notes, each checked by hand- $ hippo revert 01M77HWVY5GX5N91HTDYF1YRAWundoes any change by its receipt
Your team's agents get it through git
The notes are files in the repo. hippo init ignores what is per person. Nothing syncs live. Sharing in a team
changelog-keeperdecision-logrunbook-checktest-commands 26 reviewed packs add nightly passes. Text copied in, never code.
You can also see what they are doing
Fleet shows which session is waiting on you and how much usage each account has left.
WoGet the release branch ready to mergetern-web
waiting on you 14:58
asked: “Should I merge it into main now, or wait for the design review?”
DeTern: album covers in paralleltern-web
live · 4 sub-agents
WoCheck the gallery page and send me screenshotstern-web
interrupted 13:32
- agent working
- waiting on you
- you corrected it
Incidents what went wrong, quoted
- destructive command
no, why did you overwrite my draft
- collisionAnother session edited upload.ts 3m later while both were working
hippo xray were its claims checked?
$ hippo xray demo-x1 verified "All 12 tests pass." (turn 13) npm test · exit 0 · 12 passed · turn 11 UNVERIFIED "Deployed to production." (turn 16) no deploy command in the transcript…
Local, nothing hosted
reads~/.claude*/projects/~/.codex/sessions/~/.dsh/sessions/~/.local/share/opencode/~/.local/share/muse/sessions/~/.commandcode/projects/
writes~/.hippo/index.sqlitenotes/*.md.hippo/receipts/.hippo/snapshots/
sendsclaude -pyour own login, for the nightly check
Install
macOS and Linux
Claude Code plugin
DeepSeek Harness plugin
OpenCode plugin, in opencode.json
From source




