Cursor
SupportedPlugin with sessionStart and sessionEnd hooks, plus MCP. /hypher-brief and /hypher-handoff stay as manual overrides.
Stop re-explaining your project to every agent.
Hypher carries decisions and next steps between Claude Code and Codex. Join the pilot.
The handoff
Save in Claude Code. Resume in Codex.
One command to save, one to resume. The switch is recorded on Claude Code 2.1.294 and Codex CLI 0.161.0, and on nothing else yet.
Illustration of an explicit handoff, with sample data. Not a recording. In Claude Code, /hypher-save saves the handoff to Hypher. The note carries a decision (Hash tokens at rest), a constraint (Don't widen OAuth), unverified work (Stale-revision test) and the next step (Run it, then open the PR). In Codex CLI, $hypher-resume reads it. Code and uncommitted files do not travel with it.
Illustration of an explicit handoff. Not a recording. No code leaves the machine.
What's automatic
What's automatic, what's manual.
Today, on the pilot path. Tested client versions are listed here once the recording exists.
| Step | Cursor | Claude Code | Codex CLI |
|---|---|---|---|
| Load the note at session start | Hook, with a token — Automatic | /hypher-resume — You run it | $hypher-resume — You run it |
| Save the handoff when you stop | Hook, with a token — Automatic | /hypher-save — You run it | $hypher-save — You run it |
| Fold captures and writebacks into the note | Automatic — Automatic | Automatic — Automatic | Automatic — Automatic |
| Warn on a different branch, commit, or dirty state | Not yet — Not available yet | On resume — Automatic | On resume — Automatic |
| Approve a changed decision | You, one pin — Human only | You, one pin — Human only | You, one pin — Human only |
| Recap you type | None — Nothing to do | None — Nothing to do | None — Nothing to do |
Automatic checkpoints for Claude Code and Codex come with Baton, after the explicit switch is recorded. Cursor hooks do not run on Cursor cloud agents; those load the note through MCP.
How it works
Capture, the note, writeback.
Hypher sits under your agents. It is not another place to write code.
01
Capture
Paste the mess. Rants, screenshots, chat exports, “don't widen OAuth.” No filing tax. An agent's checkpoint is the same kind of capture.
02
The note
One bounded note per project. Decisions with reasons and who approved them. The current goal, what's done, what's only claimed, and the next action.
03
Writeback
When an agent stops, it writes back why a decision changed and what comes next. The next agent — or the next session — starts from there.
Illustrations with sample data. Not a recording.
The brief
What the next agent reads.
Not the transcript. A bounded brief: constraints first, next action last.
Current goal
What this workstream is for.
Constraints
The do-not-dos. An agent report can never relax one you set.
Decisions and why
With provenance. A change names the decision it replaces.
Done versus claimed
A reported test pass is labeled as a report, not a result.
Blockers
What stopped the last agent, in its words.
Next action
One move. The first thing the next agent does.
Sources
Which capture or writeback each line came from.
Tree identity
Repository, branch, commit, and dirty state as metadata.
Checked, not trusted
Your code never leaves your machine.
Memory does not move code. The next agent checks the working tree itself and says what differs.
Illustrations with sample data. Not a recording.
Leaves the machine
- Decisions and constraints
- Branch and commit IDs
- File names and dirty state
- The handoff you save
Never leaves
- Source code
- Diffs and uncommitted edits
- Transcripts and hidden reasoning
- Secrets
Where it works
A way into the note from each agent.
A door is not a sync of your repository. Cursor already has the code; Hypher has what never landed in the files.
Claude Code
PilotProject MCP with /hypher-save and /hypher-resume. Explicit save and resume. Switch with Codex CLI 0.161.0 recorded on Claude Code 2.1.294.
Codex CLI
PilotProject MCP with $hypher-save and $hypher-resume. Writes ask for approval. Switch with Claude Code 2.1.294 recorded on Codex CLI 0.161.0.
Any other agent
MCP or CLIAny agent that can reach the hypher MCP server or run the hypher CLI loads the note at session start and writes one handoff at the end. Not yet tested.
FAQ
A few honest answers.
What is Hypher?
Project memory under your coding agents. You capture the project as it is; Hypher keeps one note; the next agent reads it and writes back when it stops. Session two starting warm and a switch from Codex to Claude Code are the same job.
Does it work today?
Cursor works through its plugin and MCP. Claude Code and Codex CLI have an explicit save and resume path in the pilot. The switch between them is recorded on Codex CLI 0.161.0 and Claude Code 2.1.294, and we claim it only on those versions.
Do you upload my repository?
No. Only decisions, the handoff, and hashes, file names, and commit identity leave the machine. Never code, diffs, or transcripts. GitHub is a signal — CI, stale PRs, labeled blockers — not memory.
Is this Baton?
Baton is the handoff feature that makes this automatic: checkpoints while an agent works, a seal when it stops, and a check against the files on resume. It follows the recorded explicit switch. It is not shipped.
Why not a handoff file in the repo?
A file doesn't know which decision replaced which, who approved it, or whether “tests pass” was run or only claimed. And it goes stale the moment someone forgets to update it.
Does Hypher run or host my agents?
No. Your agents do the work and the reasoning. Hypher stores the note and hands it over. It does not orchestrate, schedule, or supervise anything.
Pilot
Stop re-explaining your project to every agent.
For builders who switch between Claude Code and Codex on the same repository. Small cohorts, onboarded by hand.