The 9P docs find the mount through $NINE_MOUNT, and then the editor is just files

3 files changed, 16 insertions, 9 deletions

diff --git a/.agents/skills/pardes-9p/SKILL.md b/.agents/skills/pardes-9p/SKILL.md
index 8903a609..e708d005 100644
--- a/.agents/skills/pardes-9p/SKILL.md
+++ b/.agents/skills/pardes-9p/SKILL.md
@@ -13,24 +13,29 @@ relative to that root unless linked.
 
 ## Find the session through the mount
 
-This machine keeps a FUSE mount of every posted session under `/mnt/9p`:
-`/mnt/9p/pardes/<pid>/` is one session's served root. Inside a pane,
+Check `$NINE_MOUNT` first. `9ns --mntgen` sets it for every process it starts
+(an interactive shell on this machine runs inside one), so a set `$NINE_MOUNT`
+means the posted-9P registry is mounted there, usually `/mnt/9p`, and each
+running editor is a directory `$NINE_MOUNT/pardes/<pid>/`. Inside a pane,
 `$PARDES_9P` is that session's socket (`/run/user/1000/pardes-9p-<pid>.sock`),
-so its pid is the directory to use, and `$PARDES_PANE` is the calling pane's
-serial:
+which names the directory, and `$PARDES_PANE` is the calling pane's serial:
 
 ```sh
-m=/mnt/9p/pardes/$(basename "$PARDES_9P" .sock | sed 's/^pardes-9p-//')
+[ -n "$NINE_MOUNT" ] || echo 'no 9P mount: use the Python client below'
+s=${PARDES_9P##*/pardes-9p-}; m=$NINE_MOUNT/pardes/${s%.sock}
 cat "$m/index"
 cat "$m/pane/$PARDES_PANE/body"
 ```
 
+From there the editor is files: `cat`, `echo >`, `ls` and shell scripts are
+the whole interface, and nothing below needs more than they do.
+
 Entries for dead sessions stay listed and answer `Input/output error` on any
 access, so name the session you mean rather than globbing or taking the newest.
 `cat "$m/index"` is the cheapest liveness check, and `cat "$m/status"` reports
 the `pid`, `version` and `panes` of a session new enough to serve it.
 
-`/mnt/9p/pardes` is the registry of posted sessions, mounted once for the
+`$NINE_MOUNT/pardes` is the registry of posted sessions, mounted once for the
 machine. It is not the per-pane kernel mount the `Tty9p` builtin makes, which
 gives one pane's shell `$PARDES_MOUNT`; see [docs/v9fs.md](../../../docs/v9fs.md)
 for that. Either mountpoint serves the same tree. A `9ns --unix SOCKET -- cmd`
diff --git a/docs/fs.md b/docs/fs.md
index e93704a6..0b248037 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -62,8 +62,10 @@ private namespace:
 A `9ns --unix` mount lives in the private namespace of the command it runs,
 and nothing outside that command sees it. The mount everyone on the machine
 shares is the registry one, `9ns --mntgen` (default `/mnt/9p`): every running
-editor posts itself there, so `/mnt/9p/pardes/<pid>/` is that editor's tree
-for any process. A new pane made through `pane/new` is a scratch named
+editor posts itself there, so `$NINE_MOUNT/pardes/<pid>/` is that editor's tree
+for any process. 9ns exports `$NINE_MOUNT` to everything it starts, so a
+script checks that variable to know the mount is there, and takes `<pid>` from
+the name of `$PARDES_9P` (`pardes-9p-<pid>.sock`). A new pane made through `pane/new` is a scratch named
 `<dir>/+New` until it is given a name, and closing a column's last pane
 leaves such a `+New` in its place (`Delcol` closes the column).
 
diff --git a/src/fs-help.txt b/src/fs-help.txt
index 79701628..8948ac78 100644
--- a/src/fs-help.txt
+++ b/src/fs-help.txt
@@ -16,7 +16,7 @@ pane/<n>/   name body tag ctl addr dot limit data xdata sel dirty mark scroll er
             appended to its directory's +Errors pane) event look exec, pty/ on terminals; rmdir closes
 os/, src/   the host filesystem; the editor's own sources (-Dembed-sources=true builds only)
 
-Below, $m is the mount (/mnt/9p/pardes/<pid> via 9ns --mntgen; PARDES_MOUNT in a Tty9p shell):
+Below, $m is the mount: $NINE_MOUNT/pardes/<pid> when 9ns --mntgen set $NINE_MOUNT; PARDES_MOUNT in a Tty9p shell.
 
   cat $m/index                                 which panes exist
   n=$(cat $m/pane/new)                        make a pane, take its serial