{"answer":"I have everything I need. Findings below, each tied to the line I read.\n\n🔴 `bug` services/proxy/src/sweep.rs:140: `forget` runs unconditionally, so `POST /v1/admin/cache/sweep?dry_run=true` deletes every index entry naming a blob it merely *reported* — `gone` is populated at line 137 regardless of `dry_run`. The advertised \"reports what one would reclaim without removing anything\" (docs/operations.md) silently un-caches the store, and the next real sweep then deletes those now-unreferenced blobs.\n\n🔴 `bug` services/proxy/src/metrics.rs:94: `values()` returns bytes-reclaimed where `COUNTERS[4]` is `cairn_proxy_sweep_blobs_removed_total` and blobs-removed where `COUNTERS[5]` is `cairn_proxy_sweep_bytes_reclaimed_total`; the two sweep counters are exposed under each other's names, so the alert docs/operations.md tells operators to build on `cairn_proxy_sweep_bytes_reclaimed_total` reads a blob count. Swap lines 94 and 95.\n\n🔴 `bug` services/proxy/src/sweep.rs:102: `sort_by_key(|c| c.age)` orders *ascending* age — newest first — so the over-ceiling loop evicts the blobs most recently fetched, exactly the opposite of the comment on line 100 and of the `CACHE_MIN_AGE` grace period's purpose (a fresh blob just past `min_age` goes before a year-old one). Sort by `std::cmp::Reverse(candidate.age)`.\n\n🟠 `bug` services/proxy/src/sweep.rs:232: `clear_partials` unlinks every file in `incoming` with no age or liveness test, but that directory holds the *in-flight* temp files of `BlobStore::writer` (store.rs:201) and of `BlobStore::link` (store.rs:147). A sweep firing during a 200 MiB download deletes the file under the open handle, and `BlobWriter::commit`'s rename (store.rs:259) fails with ENOENT, turning a healthy fetch into a 500. Only files older than `min_age` (or than `fetch_timeout`) are abandoned.\n\n🟠 `bug` services/proxy/src/sweep.rs:119: the \"nothing points at it\" branch ignores age, but a freshly committed blob is unreferenced for the whole of the registry round trip — cache.rs commits at line 151 and only calls `store.link` at line 163. A sweep in that window removes the blob, and the reopen at cache.rs:90 fails with \"a blob committed by this request is already missing from the store\". Unreferenced blobs must also be older than `min_age` before they are removed.\n\n🟠 `performance` services/proxy/src/sweep.rs:90: `sweep` is a synchronous full-tree `read_dir`/`metadata`/`unlink` walk, and both callers run it directly on a runtime worker — `Sweeper::run` at line 84 and the handler at routes/admin.rs:76. On the large store the module doc contemplates this parks a worker thread for the whole walk, stalling the async tasks (including in-flight artifact streams) scheduled on it. It needs `tokio::task::spawn_blocking`.\n\n🟡 `bug` services/proxy/src/routes/admin.rs:76: the route calls `sweeper.sweep(...)` and not `sweeper.run()`, bypassing the `running` mutex (sweep.rs:67) that the module doc at sweep.rs:10 says makes one-sweep-at-a-time a property of the type. Two concurrent `POST /v1/admin/cache/sweep` calls, or one racing the background tick, each size their removals against a total the other is shrinking and take the store far under the ceiling.\n\n🟡 `bug` services/proxy/src/sweep.rs:164: `fs::metadata` follows symlinks, contradicting the comment on lines 160-163 — a symlink is counted at its *target's* size, and a symlinked directory inside the blob dir makes `collect` recurse outside the store, where its files are then unreferenced and unlinked at line 126. Use `fs::symlink_metadata` and skip non-regular files.\n\n🔵 `bug` services/proxy/src/sweep.rs:120: `remaining >= self.max_bytes` removes one more blob when the store is exactly at the ceiling; the ceiling is documented as the most the store *may* hold, so this should be `>`.","auth":{"mode":"api_key"},"effort":"high","elapsed_secs":126.64,"error":null,"error_kind":null,"instructions":[],"model":"anthropic/claude-opus-5","ok":true,"sandbox":{"backend":"macOS Seatbelt","denied_read_roots":["/Users/bart.smykla@konghq.com/Projects/github.com/smykla-skalski/benchee/subjects"],"environment":["HOME","LANG","LC_ALL","PATH","TERM","TMPDIR"],"mode":"read-only","network":"denied","protected_write_roots":["/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/.git","/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/.afi","/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/.agents","/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/.codex","/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/AGENTS.md","/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs/CLAUDE.md"],"readable_paths":["/"],"readable_roots":["/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/benchee-agent-loRnxs","/bin","/sbin","/usr/bin","/usr/sbin","/usr/lib","/usr/libexec","/usr/share","/System/Library","/Library/Apple","/Library/Filesystems/NetFSPlugins","/Library/Preferences","/private/etc","/private/var/db/timezone","/private/var/db/DarwinDirectory/local/recordStore.data","/private/var/select/developer_dir","/private/var/select/sh","/opt/homebrew/bin","/opt/homebrew/Cellar","/opt/homebrew/etc/gitconfig","/opt/homebrew/lib","/opt/homebrew/opt","/usr/local/bin","/Applications/Xcode.app/Contents/Developer","/Applications/Xcode.app/Contents","/Users/bart.smykla@konghq.com/.local/bin/afi"],"writable_roots":["/private/var/folders/d1/tvmyp5cs1gz38rltf390ddpw0000gn/T/afi-sandbox-ZbAk1O"]},"schema_version":1,"source":"openrouter","sources":[{"auth":{"mode":"api_key"},"source":"openrouter","usage":{"cache_read_tokens":0,"cache_write_tokens":0,"cost_usd":0.75455,"estimated_tokens":0,"input_tokens":103695,"output_tokens":2194,"reasoning_tokens":7249,"requests":3,"total_tokens":113138}}],"system_prompt":{"file":null,"mode":"builtin"},"tools":["read_file","write_file","edit_file","list_dir","search_files","glob_files","run_bash","wait_background"],"usage":{"budget":{"converged":false,"hard_ratio":0.95,"limit_usd":12.0,"soft_ratio":0.8,"spent_usd":0.75455,"stopped":false},"cache_read_tokens":0,"cache_write_tokens":0,"cost_usd":0.75455,"estimated_tokens":0,"input_tokens":103695,"output_tokens":2194,"reasoning_tokens":7249,"refused_by_approval":0,"refused_by_policy":0,"refused_tool_calls":0,"requests":3,"total_tokens":113138}}