{
  "sha": "9b51f95ef609a219e211e37b082cd2e6913190e0",
  "model": "z-ai/glm-5.3-flash",
  "effort": "high",
  "found_per_pass": {
    "agent": 8
  },
  "findings": [
    {
      "path": "services/proxy/src/metrics.rs",
      "start_line": 88,
      "end_line": 88,
      "label": "bug",
      "severity": "critical",
      "explanation": "values()` returns `sweep_bytes_reclaimed` then `sweep_blobs_removed` (lines 94-95), but `COUNTERS` lists `cairn_proxy_sweep_blobs_removed_total` then `cairn_proxy_sweep_bytes_reclaimed_total` (lines…\n\nvalues()` returns `sweep_bytes_reclaimed` then `sweep_blobs_removed` (lines 94-95), but `COUNTERS` lists `cairn_proxy_sweep_blobs_removed_total` then `cairn_proxy_sweep_bytes_reclaimed_total` (lines 51-57) — `render()`'s zip pairs each counter with the other's name, so every scrape reports bytes under the blobs-removed metric and vice versa. `docs/operations.md` tells operators to watch `cairn_proxy_sweep_bytes_reclaimed_total`, which now shows a blob count.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/routes/admin.rs",
      "start_line": 76,
      "end_line": 76,
      "label": "bug",
      "severity": "high",
      "explanation": "reclaim` calls `app.sweeper.sweep(dry_run)` directly, bypassing the `running` mutex that only `Sweeper::run` (sweep.rs:82-85) takes.\n\nAn on-demand sweep therefore runs concurrently with the background sweep, which is exactly the two-sweeps-over-one-directory hazard sweep.rs:10-12 says the type exists to prevent: both decide what to remove from a total the other is changing, over-evicting the store far below the ceiling.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/routes/admin.rs",
      "start_line": 76,
      "end_line": 76,
      "label": "bug",
      "severity": "high",
      "explanation": "the sweep handler runs `Sweeper::sweep` — a fully synchronous `std::fs` walk and unlink pass over the whole store (sweep.rs:90-149) — directly on the async runtime worker thread.\n\nA store with tens of thousands of entries blocks the executor for the whole pass, stalling every other request including `/healthz` and `/metrics`; it needs `spawn_blocking`.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 140,
      "end_line": 140,
      "label": "bug",
      "severity": "high",
      "explanation": "forget(&index, &gone)` runs unconditionally, including on a dry run.\n\n`gone` holds every candidate the dry run *would* remove, so `?dry_run=true` — documented as reporting \"without removing anything\" — actually deletes the index entries for those blobs, turning live cache coordinates into misses and forcing refetches for an operator who was only trying a ceiling out.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 230,
      "end_line": 230,
      "label": "bug",
      "severity": "high",
      "explanation": "clear_partials` unlinks every file in `incoming` with no age check, but `incoming` also holds the temp files of fetches in flight right now (`BlobStore::writer`, store.rs:171-180, writes there until…\n\nclear_partials` unlinks every file in `incoming` with no age check, but `incoming` also holds the temp files of fetches in flight right now (`BlobStore::writer`, store.rs:171-180, writes there until commit). A sweep that lands mid-download unlinks the temp file out from under the writer; the later `fs::rename` in `BlobWriter::commit` (store.rs:259) fails with NotFound and the client's fetch fails. Needs the same `min_age` grace the blob path has.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 164,
      "end_line": 164,
      "label": "bug",
      "severity": "medium",
      "explanation": "fs::metadata` follows symlinks, so a symlink is counted (and recursed) at its *target's* size and type, not the link's — the opposite of what the comment at lines 160-163 claims (`symlink_metadata`…\n\nfs::metadata` follows symlinks, so a symlink is counted (and recursed) at its *target's* size and type, not the link's — the opposite of what the comment at lines 160-163 claims (`symlink_metadata` is what that needs). A symlinked directory is also recursed into, so a symlink cycle under the blob dir makes `collect` recurse until the stack blows.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/main.rs",
      "start_line": 115,
      "end_line": 115,
      "label": "bug",
      "severity": "low",
      "explanation": "tokio's `interval` completes its first tick immediately, so the loop sweeps straight away.\n\nThe doc comment at main.rs:101-102 claims the first tick is one interval away precisely to stop a freshly started proxy from sweeping an empty cache — the stated behaviour and the actual behaviour are opposite (harmless today only because the store is empty at startup).",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 126,
      "end_line": 126,
      "label": "bug",
      "severity": "low",
      "explanation": "when `fs::remove_file` fails, the blob is still counted — `remaining` is decremented, `bytes`/`removed` incremented (lines 134-136) — and `forget` then deletes its index entries anyway.\n\nA sweep that cannot unlink (permissions, EBUSY) reports reclaimed bytes that are still on disk and leaves blobs on disk that nothing in the index can reach.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    }
  ]
}