Server (src/http-server.ts, src/index.ts, src/selection.ts,
src/new-diagram.ts):
- overlapping get_selection calls take turns (readSelection, one slot per
session as the export slot) instead of replacing each other's request,
which left one of them with a false "tab not in front" timeout
- an answer is taken only while a request is pending (both ids undefined
compared equal)
- the tool sees the page start_session actually opens: with dist/shell
missing the classic page is in use, which never answers, so the tool
says so instead of timing out
- the result lists at most 100 cells and counts the rest: a whole large
diagram selected would fill the model's context
- every <diagram> the model sends without an id gets one, so the page id
the shell reports exists in the server's document
Shell (shell/mcp-sync-core.ts, shell/use-mcp-sync.ts,
contexts/diagram-context.tsx, lib/drawio/editor-bridge.ts):
- an answer whose POST failed is sent again at the next poll
- no answer while a full load has yet to reach the editor: it still shows
the previous document, whose cells and pages the answer would name
- a hidden tab (the same session open twice) answers a poll later, so the
tab in front answers first; alone, it still answers within the timeout
- a cell's container is reported by the model's isLayer, not by comparing
with the default parent, which is the group the user entered
Unit tests for the request plumbing (random id, one answer, timeout), the tool's texts (cells, nothing selected, external draw.io) and the shell's side (one answer per request, after draw.io is up, never during a projection); the wiring test starts a session with BROWSER=none to see the no-tab message. Shell e2e: cells selected in the editor reach get_selection; a PNG of another page differs from the page on screen, which stays.
dayuan.jiang