ph-clm

The model edits its own context: tombstone, replace and rewrite sections of what it sees, with every original kept in the log.

After Context Language Models: a model keeps the context it works best with when it may edit that context itself. In pH an edit never rewrites the log. Each one is a surface replace — the mechanism compaction and paste offload already use — so the model's view changes, the log keeps the originals, and the person's transcript still shows the conversation they had.

Sections

The model's context is cut into sections where no tool call is outstanding: a user message, an assistant reply, or an assistant message with every result it asked for. Each is named by the seq of its first event (S412), which never changes, so an id read on one call is good on the next.

Tools

Every edit reports what it costs: a provider's prefix cache cannot serve anything after the first change, so the sections after an edit are read again once.

Readouts

When a tool result takes the context past a share of its window, that result ends with one line giving the context's size and how to free space. Each share is reported once, and again only after an edit brings the context back below it. The shares are the clm-context row's remindAt, [0.5, 0.75] by default; [] turns readouts off. With compaction mounted, the last reminder comes lastMargin (0.2) below its trigger instead, 65% under the default 0.85, so the model has room to act before a summary is written for it. Under Code Mode the readout spells the call out, keywords and all.

The context file

The clm-mirror row writes the model's context to a file in the agent's workspace scratch before each request, one [[SECTION S<id>]] block per section. The model edits it with whatever it already uses: edit, sed, Python in a cell. When the call that touched the file finishes, its changes land through the same editor the tools use, in one batch, before the call's result. The result carries the receipt.

A revised section's header line says what it stands for. The text under it is only what the model may edit.

A reorder, a damaged header, an edit to a protected section, or a file written before the context was last revised is refused. The call's result says why, and the file is rewritten.

The file is a whole conversation, so it is kept private and short-lived:

• its directory is 0700 and the file 0600;
• it is deleted when the session leaves the store;
• a link put in its place is replaced, never read through.

Only an edit a tool call makes is applied. A file changed outside any call (in an editor, or by another process) is recorded as declined and rewritten before the next request.

phern --profile rlm-clm