{
  "sha": "9b51f95ef609a219e211e37b082cd2e6913190e0",
  "model": "anthropic/claude-fable-5",
  "effort": "high",
  "found_per_pass": {
    "agent": 7
  },
  "findings": [
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 140,
      "end_line": 140,
      "label": "bug",
      "severity": "critical",
      "explanation": "forget(&index, &gone)` is not gated on `dry_run` and `gone` is filled even in a dry run (lines 136-137 run unconditionally), so `POST /v1/admin/cache/sweep?dry_run=true` really unlinks the index…\n\nforget(&index, &gone)` is not gated on `dry_run` and `gone` is filled even in a dry run (lines 136-137 run unconditionally), so `POST /v1/admin/cache/sweep?dry_run=true` really unlinks the index entries of every blob it merely reported — the blobs it \"did not remove\" become unreachable cache misses immediately and are deleted as unreferenced on the very next real sweep, the opposite of the documented \"reports … without removing anything\".",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 102,
      "end_line": 102,
      "label": "bug",
      "severity": "critical",
      "explanation": "sort_by_key(|c| c.age)` orders candidates  youngest first  (smallest `now - mtime` first), yet the eviction loop removes from the front, so an over-ceiling sweep deletes the most recently fetched…\n\nsort_by_key(|c| c.age)` orders candidates  youngest first  (smallest `now - mtime` first), yet the eviction loop removes from the front, so an over-ceiling sweep deletes the most recently fetched blobs and keeps the oldest — an inverted LRU that thrashes exactly the packages current builds are using; the sort needs to be descending by age.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/sweep.rs",
      "start_line": 119,
      "end_line": 119,
      "label": "bug",
      "severity": "high",
      "explanation": "a blob with no index entry is removed with no `min_age` grace, but on the miss path a blob exists unlinked for the whole window between `writer.commit()` (services/proxy/src/routes/cache.rs:151) and…\n\na blob with no index entry is removed with no `min_age` grace, but on the miss path a blob exists unlinked for the whole window between `writer.commit()` (services/proxy/src/routes/cache.rs:151) and `store.link()` (cache.rs:163), which includes a network round-trip to the registry — a sweep in that window deletes the just-committed blob and the request 500s at cache.rs:90; reading the index snapshot (line 92) *before* walking blobs (line 95) widens the race further.",
      "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 or liveness check, but `incoming` is where `BlobWriter` (store.rs:171-180) is actively writing in-flight downloads — a sweep during a…\n\nclear_partials` unlinks every file in `incoming` with no age or liveness check, but `incoming` is where `BlobWriter` (store.rs:171-180) is actively writing in-flight downloads — a sweep during a fetch unlinks the live temp file, and `commit`'s `fs::rename` (store.rs:259) then fails with NotFound, failing the request; the doc's claim that \"a file in `incoming` is a fetch that is not coming back\" is false while any fetch is in flight.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/metrics.rs",
      "start_line": 94,
      "end_line": 94,
      "label": "bug",
      "severity": "high",
      "explanation": "values()` loads `sweep_bytes_reclaimed` at index 4 and `sweep_blobs_removed` at index 5, but `COUNTERS` (lines 50-57) names index 4 `cairn_proxy_sweep_blobs_removed_total` and index 5…\n\nvalues()` loads `sweep_bytes_reclaimed` at index 4 and `sweep_blobs_removed` at index 5, but `COUNTERS` (lines 50-57) names index 4 `cairn_proxy_sweep_blobs_removed_total` and index 5 `..._bytes_reclaimed_total` — each sweep counter is exported under the other's name, which is precisely the mix-up the comment on `COUNTERS` warns about, and docs/operations.md tells operators to alert on the bytes counter that will actually carry the 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": "the admin route calls `app.sweeper.sweep(dry_run)` directly instead of `run()`, skipping the `running` mutex (sweep.rs:83), so an on-demand sweep runs concurrently with the background sweep (or…\n\nthe admin route calls `app.sweeper.sweep(dry_run)` directly instead of `run()`, skipping the `running` mutex (sweep.rs:83), so an on-demand sweep runs concurrently with the background sweep (or another admin sweep) — the exact two-sweeps-over-one-total situation the module doc (sweep.rs:10-12) says must never happen, each deleting from a total the other is changing.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    },
    {
      "path": "services/proxy/src/routes/admin.rs",
      "start_line": 76,
      "end_line": 76,
      "label": "performance",
      "severity": "medium",
      "explanation": "sweeper.sweep()` is a fully synchronous filesystem walk (readdir + stat over up to 65k directories, plus reading every index file) executed inline on a tokio worker thread — routes/mod.rs:125 itself…\n\nsweeper.sweep()` is a fully synchronous filesystem walk (readdir + stat over up to 65k directories, plus reading every index file) executed inline on a tokio worker thread — routes/mod.rs:125 itself says a sweep \"legitimately takes longer than ten seconds\" — blocking that runtime thread for the duration; the same applies to `app.sweeper.run().await` in the spawned task at services/proxy/src/main.rs:116; both should go through `spawn_blocking`.",
      "evidence": null,
      "suggested_fix": null,
      "deterministic": false
    }
  ]
}