sage: row 65 landing notes, c216f47db with gate g3 green, the mos-0840 Routing view, the plugins set patch for Jason, follow-up 5 (#1558)

agents/sage/work/queue-65/BUILD.md

@@ -172,6 +172,9 @@ Follow-ups, no change in this row (Darkwing's notes):
 3. `adapter()` and `mounts()` run after the workspace and session dirs exist; a throw there
    leaves them behind.
 4. `mosaic-bus.service.in:16-17` still names `claudeVersion`. Already on the row 166 list above.
+5. Darkwing and Dewey, round 2: when the chief of staff sends a partial fallback through
+   `assistants`, the write is refused, but with `invalid-request` instead of
+   `organization-partial-fallback`. The refusal holds; only the code is less exact.
 
 ## Tests
 
@@ -249,3 +252,28 @@ exit and no container was left.
 At landing Sage sends Jason, through Mos, the patch for the live business file:
 `mosaic plugins set` adding `"harness": ["claude-code"]`. Nothing goes live before a re-pin on
 Mos's go. Until that patch is in, a new launch refuses `harness-off`.
+
+Landed 2026-10-19 as c216f47db, 8d7c9e2f1 cherry-picked onto 866f3c5a8 with the round 2 message.
+Approvals: Darkwing 29144 (rev 1953) and Dewey 29145 (rev 1954), both on manifest 8df15e39.
+Between 89ddb0225 and 866f3c5a8 only this packet, the queue files and SESSIONS changed, none of
+them a candidate path. The landed commit's path list has the same sha256 as the candidate's, all
+64 manifest hashes check against the landed tree, and the public/ +/- digest is a91cf866, the one
+Mos cleared (mos-0841 condition 3).
+
+Gate g3 (`/mnt/storage/scratch/sage-r65-out/gate3.sh`) on c216f47db, `dirty 0`: GATE_PASSED, 25
+steps, each rc=0. 2514 node tests (2358 package, 156 in test-queue) and 422 script selftests, 0
+failed, summed with awk over `g3.console.txt`, the same counts as g2. The same one webui skip.
+Network `sage-r65_default` removed, no container left.
+
+The mos-0840 view is the Routing section of the Console's Settings page (`<h2
+id="routes-title">Routing</h2>` in `packages/webui/src/public/bus.js`), which replaces the Role
+models fieldset.
+
+The patch for Jason, sent through Mos: read the revision with `mosaic plugins --business
+mosaic-stack --json`, then run `mosaic plugins set --business mosaic-stack --file PATCH` with
+`{"revision": "<that revision>", "plugins": {"harness": ["claude-code"]}}`. A kind the patch
+doesn't name keeps its setting, so this adds harness to whatever `plugins` holds. It works only
+on a stack pinned past c216f47db: an older setter refuses the harness kind as unknown. A new
+bind reads `plugins.harness` from the file as it stands, so no bus restart is needed for it.
+After that Sage runs one managed coder session and attaches the manifest (module, route,
+counted model, thinking).