# v2.1 implementation plan: fixes found while running v2

> **For the implementing model:** do not work from this file. The owner gives you one task file at
> a time. This file is the index for the owner and the reviewer.

**Goal:** close the two defects and one gap found while v2 ran, without new features.

- **01-cancel-record** — a delivered response is never recorded as a 499; cancellation is what
  the reverse proxy observed. Found 2026-09-25 by the intermittent `Errors:2` in
  `TestQueueFullIs503`; verified with a diagnostic build; the given
  `internal/proxy/served_test.go` reproduces it on every run.
- **02-props-loaded-only** — on a router only `status.value == "loaded"` counts as loaded; the
  poller asks `/props?model=X` only for those (the router autoloads a model named in that query)
  and keeps the answers per model (`Status.Models`, `PerSlotCtxFor`); the guard and the hosts view
  use them. Facts verified against straylight's router on 2026-09-25. Given tests:
  `health/props_router_test.go`, `proxy/ctxguard_router_test.go`, `admin/admin_models_test.go`.
- ~~03-timing-margins~~ — done by the owner directly (test-only work, no implementer task): the
  remaining ordering sleeps in `limiter_test.go`, `proxy_test.go` and `cancel_test.go` now wait on
  limiter state (`Queued`/`InFlight`); the one sleep left is a deliberate lower bound. Five clean
  `-race` runs of both packages except the 499 defect task 01 fixes.

**How this plan was made:** acceptance tests first; no reference implementation. The given test
for task 01 was run against the v2 tree (fails six of six) and against a throwaway fix that
follows the task's rule (passes four full package runs with the v1 cancel tests); the throwaway
was discarded.

## Global constraints

- Everything in `AGENTS.md`. Branch `v2.1` from `master` after v2 merges. One task, one fresh
  OpenCode session, one commit. Given files are copied and never edited.

## Changes during the run

- 2026-09-25, task 01, first session: 8 minutes of reading, then it tried to read Go's
  `httputil/reverseproxy.go` from the nix store, the sandbox refused, and it ended the turn
  without a commit — the eighth refusal-ending of the day. Model fault, but the want was
  legitimate: the task now states the `ReverseProxy` facts it was after and says the standard
  library cannot be read from the sandbox. Restarted.
- 2026-09-25, task 02: the given `ctxguard_router_test.go` asserts `X-Crossbar-Ctx: moved:small>big`;
  v2's code emitted `moved:small><big`. Owner fault twice over: the v2 task 02 text wrote the
  separator as `<from>>><to>` (ambiguous), and no v2 given test asserted the header, so the
  misreading passed. The example in that task (`moved:small>big`) is the intended format; Ornith
  changed `movedHeader` to match and said so. Accepted as part of task 02.