fix(claim): serialize generated-tokens record writes to save nonces - #2928
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backfillGeneratedClaimTokens preserves an existing generated-tokens record's own nonce by reading it, then writing the backfilled record back with that captured value. Nothing serialized that read-then-write against a concurrent plain --record-tokens --nonce call (the activation-nonce minting flow's own second write), and every write to this file was a plain atomicReplaceFile replace rather than a compare-and-swap, so the interleaving could silently clobber a fresher nonce with the stale value backfill captured moments earlier (flagged by CodeRabbit against PR #2917). Close the gap by serializing every read and/or write of the generated-tokens record for a given claim-id through one withGeneratedTokensWriteLock critical section, guarded by a same-directory `.writelock` file created via a plain wx-flag exclusive create (existence alone needs no atomic-visibility trick, unlike the claim lock body's own linkSync fix for #2920, since nothing ever reads this guard file's content). Both recordGeneratedClaimTokens and backfillGeneratedClaimTokens now share the same lock keyed by the record's own path, so a concurrent write either completes entirely before backfill's read (and is correctly preserved) or entirely after backfill's write (an expected, non-lossy last-writer-wins overwrite) -- never invisibly in between. Add a deterministic worker_threads + Atomics regression test that reproduces the exact race (verified to fail against the prior unlocked code) and asserts the concurrent writer's nonce always survives. Closes #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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📝 WalkthroughWalkthroughGenerated-token writes now use an ownership-aware, fail-closed per-record lock. Backfill performs its nonce read and write inside one critical section. Instructions-only procedures and regression tests match the new locking behavior. ChangesGenerated-token write locking
Priority: ➖ Normal Estimated code review effort: 4 (Complex) | ~45 minutes Change: Bug fix · Severity of issue fixed: Medium Sequence Diagram(s)sequenceDiagram
participant backfillGeneratedClaimTokens
participant withGeneratedTokensWriteLock
participant GeneratedTokensRecord
backfillGeneratedClaimTokens->>withGeneratedTokensWriteLock: acquire exclusive record lock
withGeneratedTokensWriteLock-->>backfillGeneratedClaimTokens: grant access or return timeout error
backfillGeneratedClaimTokens->>GeneratedTokensRecord: read existing nonce by path
backfillGeneratedClaimTokens->>GeneratedTokensRecord: write record with preserved nonce
withGeneratedTokensWriteLock->>GeneratedTokensRecord: remove owned guard
Merge Risk: 🔵 Low · up to The implementation is sound, but the fallback documentation should scope cleanup to guards created by the current invocation before merge. 🚥 Pre-merge checks | ✅ 5✅ Passed checks (5 passed)
✨ Finishing Touches📝 Generate docstrings
🧪 Generate unit tests (beta)
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🟡 Changes recommended
Critical locking races and an unsupported fallback writer remain, and the contention test needs reliable synchronization.
Once you've addressed the issues Copilot identified, you can request another Copilot review.
Pull request overview
This PR serializes generated-token record writes to prevent nonce loss during concurrent backfills.
Changes:
- Adds per-record
.writelocksynchronization and stale-guard recovery. - Protects backfill read-modify-write operations.
- Adds concurrency and orphaned-lock regression tests.
- Updates the generated JavaScript helper.
File summaries
| File | Summary |
|---|---|
tests/claim-lock.test.mts |
Adds concurrency and recovery tests; the readiness signal may make the contention test vacuous. |
src/scripts/claim-lock.mts |
Implements locking, but stale-guard reclaim can remove another owner’s guard, and the fallback writer bypasses the protocol. |
scripts/claim-lock.mjs |
Generated runtime equivalent of the locking implementation. |
Review details
Suppressed comments (1)
tests/claim-lock.test.mts:1535
- The readiness flag is published before
recordGeneratedClaimTokensis invoked, so the main thread can observeints[2]and then the worker can be descheduled before its first.writelockattempt. The 250 ms timeout can therefore pass even against an unlocked implementation, making this regression test vacuous under load. Signal readiness after the lock-acquisition attempt (or add a handshake from inside that path) so the assertion proves the writer is actually blocked.
import(cliUrl).then(({ recordGeneratedClaimTokens }) => {
Atomics.store(ints, 2, 1);
Atomics.notify(ints, 2);
const outcome = recordGeneratedClaimTokens(worktree, {
- Files reviewed: 3/3 changed files
- Comments generated: 2
- Review effort level: Lite
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Inline comments:
In `@src/scripts/claim-lock.mts`:
- Around line 800-811: Update withGeneratedTokensWriteLock to remove automatic
stale-lock reclamation and fail closed after the timeout, requiring explicit
orphan cleanup; remove the stale-reclaim branch that unlinks lockPath after
isStaleGeneratedTokensWriteLock. Regenerate the corresponding compiled
claim-lock.mjs output.
- Line 1075: Update backfillGeneratedClaimTokens to resolve path before
withGeneratedTokensWriteLock and use a path-based reader inside the callback
instead of readGeneratedClaimTokens(worktree, claimId), while preserving
existing validation. Regenerate the generated scripts/claim-lock.mjs artifact
and remove the “within microseconds” guarantee from the lock documentation.
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Three independent reviewers (Codex, Copilot, CodeRabbit) on PR #2928 converged on the same finding: the stale-guard reclaim this branch added to withGeneratedTokensWriteLock was itself an ABA race. Two callers could both classify the same aged guard as stale, and the second's unconditional unlink could delete the first reclaimer's fresh replacement (or a still-live holder's own guard), letting two callers enter the critical section at once and reintroducing the exact nonce clobber this lock exists to prevent. Remove automatic reclaim entirely and fail closed after the wait budget with a clear manual-recovery message instead, matching this repository's own precedent for exactly this failure mode (#2389's clone-scoped lock: mtime staleness, then PID staleness, then removal in favor of a timeout naming the lock path for manual cleanup). CodeRabbit separately flagged that backfillGeneratedClaimTokens's critical section re-resolved the record's path via readGeneratedClaimTokens(worktree, claimId), which shells out to `git rev-parse` -- a synchronous spawn that can cost tens of milliseconds, needlessly stretched inside the write-lock's held guard. Add a path-based readGeneratedTokensAtPath and use it with the already-resolved path instead. Soften the lock's doc comments away from a "microseconds" guarantee now that the guarded section is real, synchronous disk I/O, not just in-memory work. Copilot separately flagged that the concurrent-write regression test could still pass vacuously: the writer's readiness signal fired right after its own `import()` resolved, leaving a scheduling gap before its actual lock-acquire attempt where the writer could be preempted. Signal readiness from inside a fs.writeFileSync interception at the exact `.writelock` wx-attempt instead, closing that gap completely. Drop the orphaned-guard self-heal test, since that behavior no longer exists. Copilot also flagged that the `instructions-only` fallback protocol documented for adopters without helper runtime -- the distributed default profile -- never described this write-lock coordination at all, so a session following that fallback (or a mixed helper/fallback deployment sharing a worktree) could still lose a nonce the same way. Document the same coordination in the canonical idd-template/docs/idd-helper-scripts.md source and resync the mirror. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🟡 Changes recommended
Address stale-lock recovery, guarded reads, and applicable documentation sync verification.
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Review details
Suppressed comments (2)
idd-template/docs/idd-helper-scripts.md:2211
- This PR changes the sync-managed documentation pair:
idd-template/docs/idd-helper-scripts.mdis the canonical source fordocs/idd-helper-scripts.md(audit/sync-manifest.json:592-602). The verification checklist therefore cannot accurately say “no docs changed; not applicable”; please runpnpm run docs:sync:checkand report the result (or update the checklist to explain the applicable docs-sync verification).
- **`instructions-only` write-lock coordination** (#2922 -- applies to
this write side and to the backfill side below, which performs a
read-then-write of the same record): before writing, coordinate
against a concurrent writer for the same `{claim-id}` the way the
CLI's `recordGeneratedClaimTokens` and `backfillGeneratedClaimTokens`
src/scripts/claim-lock.mts:847
readGeneratedClaimTokensremains outsidewithGeneratedTokensWriteLock, so the new lock does not actually serialize all record readers as the surrounding contract describes. On Windows,atomicReplaceFileremoves the old target before renaming the replacement, and this read maps the resultingENOENTtoabsent; a concurrent--read-tokenscan therefore observe a transient missing record during a guarded write. Either guard this read too, or change the contract and use a retry/atomic-read strategy that cannot report a transientabsent.
return readGeneratedTokensAtPath(
resolveGeneratedTokensPath(cwd, claimId),
claimId,
);
- Files reviewed: 5/5 changed files
- Comments generated: 1
- Review effort level: Lite
Codex (PR #2928 round 2) flagged that withGeneratedTokensWriteLock's finally block silently swallowed a failed guard-file unlinkSync even when the write itself succeeded, so a transient release failure (for example a Windows filesystem error) left a caller reporting success while the guard file stayed behind, undetected until a later caller waited out a full timeout with no clue why. Restructure so a critical()-failure cleanup stays best-effort (never masking the real error), while a release failure after critical() succeeds now propagates instead of being swallowed. Copilot separately flagged that the lock's own doc comment could be read as claiming full reader/writer serialization, when in fact only the two mutating call sites participate -- a standalone readGeneratedClaimTokens call stays lock-free, and on Windows a pre-existing, unrelated gap in atomicReplaceFile's existing-file replace path (also already present for the claim lock file's own overwrite path) means such an unguarded read can in principle observe a transient "absent" during any write. Document the scope explicitly rather than changing read behavior, which is a separate design question outside #2922. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🔵 Needs a closer look
Two moderate review findings remain regarding orphaned-lock coverage and the concurrency test’s readiness signal.
Review details
Suppressed comments (2)
src/scripts/claim-lock.mts:830
- The new fail-closed timeout is part of the write-lock recovery contract, but the added regression test exercises only successful contention and never verifies an orphaned
.writelock. Add coverage that pre-creates the guard, invokes a record/backfill write, and asserts it fails with the guard path without changing the record; otherwise a future timeout/reclaim change could silently reintroduce an unsafe write path.
if (Date.now() >= deadline) {
throw new Error(
`Timed out waiting for the generated-tokens write lock at ${lockPath}; ` +
`a crashed holder may have left it behind. Remove ${lockPath} ` +
`to recover (only safe once you have confirmed no live process ` +
`still holds it).`,
tests/claim-lock.test.mts:1554
- The readiness flag is set before
originalWriteFileSyncactually attempts the exclusive create. If this worker is preempted after theAtomics.store, the main thread can observeints[2]and pass the 250 ms non-settlement assertion before the writer has touched the guard at all, so the test does not prove the claimed mutual exclusion. Signal in afinallyaroundoriginalWriteFileSync(after anEEXISTattempt as well as a successful create) instead.
Atomics.store(ints, 2, 1);
Atomics.notify(ints, 2);
}
return originalWriteFileSync(path, data, opts);
- Files reviewed: 5/5 changed files
- Comments generated: 0 new
- Review effort level: Lite
Copilot (PR #2928 round 3, suppressed findings) flagged two test-only gaps. First, the regression suite only ever exercised successful contention (a guard released partway through the wait), never the other documented outcome -- a guard that is never released -- so a future change reintroducing an unsafe reclaim, or dropping the timeout check, would go uncaught. Add a test that pre-creates a `.writelock` guard, confirms `recordGeneratedClaimTokens` throws after the wait budget naming the guard path, and confirms neither the record nor the guard was touched. Second, the concurrent-write test's writer worker still signaled readiness one statement before its actual lock-acquire attempt (a smaller residual of the same gap an earlier round already narrowed), so a preempted worker could in principle let the main thread's non-settlement check pass before the writer had touched the guard. Move the signal into a `finally` around the real `writeFileSync` call so it fires only once the attempt has genuinely completed. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🟡 Changes recommended
Guard creation failures can leave a stale lock that blocks later writers until manual cleanup.
Once you've addressed the issues Copilot identified, you can request another Copilot review.
Review details
- Files reviewed: 5/5 changed files
- Comments generated: 1
- Review effort level: Lite
Copilot (PR #2928 round 4) flagged that the guard-file create attempt could still leave a `.writelock` behind on a non-EEXIST failure: `wx`'s own open+write+close sequence can create the file (making it visible) before a later step in that same call fails, e.g. ENOSPC during the write. The existing catch only handled EEXIST, so any other error rethrew immediately with nothing at `lockPath` ever cleaned up, and every later writer would wait out the full timeout and fail closed until an operator manually removed it. Unlike the ABA-prone stale-guard reclaim already removed earlier in this PR, cleaning up here carries no ownership-safety risk: excluding EEXIST means this exact call -- never a prior or concurrent holder -- is the only possible owner of whatever now exists at `lockPath`, so a best-effort unlink before rethrowing is always safe, matching the same swallow-cleanup-errors-never-mask-the-real-one pattern already used elsewhere in this function. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🟡 Changes recommended
Lock cleanup can delete another process’s guard after a failed creation attempt; ownership-safe cleanup is required.
Once you've addressed the issues Copilot identified, you can request another Copilot review.
Review details
Suppressed comments (1)
idd-template/docs/idd-helper-scripts.md:2220
- The helper-free protocol only says to remove the guard "when done." If an instructions-only read or write fails after this invocation creates the guard, an agent can stop before cleanup and leave an orphaned
.writelock; every later writer then waits five seconds and fails closed. Require afinally/shelltrapcleanup on both success and operation failure, while leaving a pre-existing guard untouched.
it); then remove the guard file when done. The guard file's own
content is never read by anything -- its mere existence is the whole
coordination signal, so no atomic-visibility trick is needed for it,
- Files reviewed: 5/5 changed files
- Comments generated: 1
- Review effort level: Lite
Copilot (PR #2928 round 5) flagged that round 4's fix was not ownership-safe: on a non-EEXIST failure from writeFileSync(lockPath, ..., { flag: 'wx' }), the code assumed this call was the sole possible owner of whatever now existed at lockPath and unlinked it unconditionally. That assumption was wrong for a failure at open() itself (for example EMFILE) -- nothing was created by this call in that case, so a concurrent process could legitimately create or already own lockPath between the failed attempt and the unlink, and the cleanup would delete that other process's live guard, letting a third writer in concurrently. Switch the create step from a single writeFileSync call to explicit openSync/writeSync/closeSync so ownership can be tracked precisely: a successful openSync(path, 'wx') is syscall-proof this call exclusively created the file, so only a failure after that point (finishing the write, or closing the descriptor) is safe to clean up. A failure at openSync itself now touches nothing, matching the reviewer's own suggested fix. Updated the concurrent-write regression test's own fs interception to match: it now intercepts fs.openSync (production's actual exclusive-create call) instead of fs.writeFileSync, which the refactor left it no longer observing. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
Copilot (PR #2928 round 4, suppressed finding) flagged that the instructions-only write-lock coordination bullet added earlier in this PR only said to remove the guard "when done," without distinguishing success from a failed write. An agent following that recipe literally could remove the guard solely after a successful write and skip cleanup on a failed one, leaving the exact orphaned-guard problem the CLI's own code was independently reviewed for -- every later writer for that claim-id then waits the full timeout and fails closed until an operator intervenes. State explicitly that removal belongs on every exit path (a shell trap, or the agent's own equivalent of a finally block), not only the happy path, and clarify that a pre-existing guard this invocation did not itself create is never removed on any path. Edited the canonical idd-template/docs/idd-helper-scripts.md source and resynced the docs/idd-helper-scripts.md mirror. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🟢 Approval recommended
The implementation and tests are complete; remaining comments are minor documentation nits.
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Suppressed comments (2)
docs/idd-helper-scripts.md:2215
- This new coordination also makes
--record-tokensfail after a 5-secondEEXISTwait, even when no filesystem error occurred; the existing contract at line 2073 still says it exits 0 unless a filesystem error occurs. Please update that contract (and the canonical source) to document lock-timeout failures and their nonzero exit behavior, so callers are not given a false success guarantee.
- **`instructions-only` write-lock coordination** (#2922 -- applies to
this write side and to the backfill side below, which performs a
read-then-write of the same record): before writing, coordinate
against a concurrent writer for the same `{claim-id}` the way the
CLI's `recordGeneratedClaimTokens` and `backfillGeneratedClaimTokens`
do (`withGeneratedTokensWriteLock`, `src/scripts/claim-lock.mts`):
atomically create a same-directory `<resolved-path>.writelock` guard
file (exclusive create -- fails if it already exists), retrying
roughly every 5 ms for up to 5 seconds if it does; only once that
idd-template/docs/idd-helper-scripts.md:2215
- This new coordination also makes
--record-tokensfail after a 5-secondEEXISTwait, even when no filesystem error occurred; the existing contract at line 2073 still says it exits 0 unless a filesystem error occurs. Please update that contract (and the generated mirror) to document lock-timeout failures and their nonzero exit behavior, so callers are not given a false success guarantee.
- **`instructions-only` write-lock coordination** (#2922 -- applies to
this write side and to the backfill side below, which performs a
read-then-write of the same record): before writing, coordinate
against a concurrent writer for the same `{claim-id}` the way the
CLI's `recordGeneratedClaimTokens` and `backfillGeneratedClaimTokens`
do (`withGeneratedTokensWriteLock`, `src/scripts/claim-lock.mts`):
atomically create a same-directory `<resolved-path>.writelock` guard
file (exclusive create -- fails if it already exists), retrying
roughly every 5 ms for up to 5 seconds if it does; only once that
- Files reviewed: 5/5 changed files
- Comments generated: 0 new
- Review effort level: Lite
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Inline comments:
In `@docs/idd-helper-scripts.md`:
- Around line 2218-2220: Scope guard cleanup to guards owned by the current
invocation: arm the cleanup handler only after the exclusive guard-file create
succeeds, so failed acquisition or wait exhaustion cannot remove a pre-existing
holder’s guard. Apply the identical wording in docs/idd-helper-scripts.md lines
2218-2220 and idd-template/docs/idd-helper-scripts.md lines 2218-2220.
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CodeRabbit (PR #2928 round 6) flagged that the previous round's success-and-failure cleanup wording could be misread as authorizing a cleanup handler armed before the guard's own create attempt -- the sentence clarifying that a pre-existing guard is never removed appeared several sentences later in the same paragraph, after the cleanup instruction itself. An agent arming a shell trap too early would remove a concurrent holder's guard on its own EEXIST or on wait exhaustion, reopening the ABA race the CLI side already closed. State explicitly, at the point cleanup is introduced rather than only later in the paragraph, that the handler must be armed only after this invocation's own create call has actually succeeded, and explain why arming it earlier is unsafe (mirrors the CLI's own openSync/writeSync/closeSync ownership-tracking rationale). Edited the canonical idd-template/docs/idd-helper-scripts.md source and resynced the docs/idd-helper-scripts.md mirror. Refs #2922 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
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🔵 Needs a closer look
Concurrent file-locking behavior warrants final human review, with two documentation/guarantee clarifications noted.
Review details
Suppressed comments (2)
idd-template/docs/idd-helper-scripts.md:2214
- The preceding write-side fallback says that no exclusive-create semantics are needed and that a plain atomic replace is correct, while this new section requires an exclusive-created
.writelock. Because both instructions apply to the sameinstructions-onlypath, an implementer can follow the earlier sentence and omit the guard, reopening the nonce-clobber race. Clarify that only the record replacement is plain; the separate guard must be exclusive-created.
- **`instructions-only` write-lock coordination** (#2922 -- applies to
this write side and to the backfill side below, which performs a
read-then-write of the same record): before writing, coordinate
against a concurrent writer for the same `{claim-id}` the way the
CLI's `recordGeneratedClaimTokens` and `backfillGeneratedClaimTokens`
do (`withGeneratedTokensWriteLock`, `src/scripts/claim-lock.mts`):
atomically create a same-directory `<resolved-path>.writelock` guard
file (exclusive create -- fails if it already exists), retrying
src/scripts/claim-lock.mts:775
- The PR description says this change serializes every generated-tokens read and write, but the implementation deliberately leaves standalone
readGeneratedClaimTokens/--read-tokenscalls outside this lock. Those readers can still observe the existing Windows remove-then-rename gap as a transientabsentresult, so narrow the PR description's guarantee to participating writes and the backfill read-modify-write sequence.
* **Scope: writers only, not a general readers/writers lock** (#2922
* review, Copilot). A standalone {@link readGeneratedClaimTokens} /
* {@link readGeneratedTokensAtPath} call made *outside* another write's own
* `critical` callback is never guarded by this lock -- only the two
* call sites that mutate the record (this file's own `recordGeneratedClaimTokens`
- Files reviewed: 5/5 changed files
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| try { | ||
| closeSync(fd); |
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If the first closeSync(fd) reports a delayed filesystem error after the OS has already released the descriptor, this catch closes the same numeric descriptor a second time. In a process using worker threads, another thread can reuse that number between the calls, causing this retry to close an unrelated file and disrupt its I/O. Treat a closeSync error as terminal and proceed with guard cleanup/rethrow rather than retrying the close.
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Summary
backfillGeneratedClaimTokenspreserves an existing generated-tokensrecord's own
nonceby reading it, then writing the backfilled recordback with that captured value. Nothing serialized that read-then-write
against a concurrent plain
--record-tokens --noncecall (theactivation-nonce minting flow's own second write for the same
claim-id), and every write to this file was a plain
atomicReplaceFilereplace, not a compare-and-swap — so the interleaving could silently
clobber a fresher nonce with the stale value backfill captured moments
earlier (flagged by CodeRabbit against PR #2917).
This PR serializes every read and/or write of the generated-tokens
record for a given claim-id through one
withGeneratedTokensWriteLockcritical section, guarded by a same-directory
<record>.writelockfilecreated via a plain
wx-flag exclusive create (existence alone needsno atomic-visibility trick, unlike the claim lock body's own
linkSyncfix for #2920, since nothing ever reads this guard file's content).
Both
recordGeneratedClaimTokensandbackfillGeneratedClaimTokensnow share the same lock keyed by the record's own path, so a
concurrent write either completes entirely before backfill's read (and
is correctly preserved) or entirely after backfill's write (an
expected, non-lossy last-writer-wins overwrite) — never invisibly in
between. If the wait budget is exhausted (a guard orphaned by a killed
process, or genuine contention), the caller fails closed with a clear
message naming the guard path for manual recovery, rather than
attempting an automatic reclaim — an earlier revision of this PR did
attempt automatic mtime-based reclaim, but three independent reviewers
(Codex, Copilot, CodeRabbit) identified it as its own ABA race (two
callers could both classify the same guard as stale, and the second's
unconditional unlink could delete the first's fresh replacement or a
still-live holder's own guard), so it was removed in favor of the
fail-closed behavior, matching this repository's own established
precedent for the same failure mode (#2389's clone-scoped lock).
Added a deterministic
node:worker_threads+Atomicsregression testthat reproduces the exact race (verified locally to fail against the
prior unlocked code before the fix was restored) and positively proves
mutual exclusion — including that a concurrent writer's own lock-acquire
attempt genuinely stays blocked while the reader holds the guard, not
merely a wall-clock timing coincidence.
The
instructions-onlyfallback protocol documented for adopterswithout helper runtime (the distributed default profile) never
described this write-lock coordination, so a session following that
fallback — or a mixed helper/fallback deployment sharing a worktree —
could still lose a nonce the same way; the canonical
idd-template/docs/idd-helper-scripts.mdsource now documents the samecoordination, and the
docs/idd-helper-scripts.mdmirror is resynced.Process note: this session implemented the fix before posting the
B2 plan comment on the issue, so it disclosed that reordering there
rather than silently skipping the step —
issue #2922.
Linked issue
Closes #2922
Follow-up issues (if any)
Background / rationale (if material)
and the pre-existing
idd-claim.lock, so it never interferes witheither's own collision/directory-guard semantics (the
record-blockeddirectory-guard path from PR feat(claim): persist generated claim tokens on disk #2879/feat(claim): backfill route for a generated-tokens record missing on a pre-existing claim #2917 is untouched by this diff).
linkSync/hard-link dependency is introduced — the guard onlyneeds existence-based exclusivity (
O_CREAT | O_EXCL/CREATE_NEW),which is already relied on elsewhere in this file across platforms.
backfillGeneratedClaimTokens's critical section now reads therecord via a path-based reader using its own already-resolved path,
rather than re-resolving it through
git rev-parsewhile holding thewrite-lock guard (CodeRabbit review) — that spawn is a genuine,
if usually small, cost that has no reason to run inside the lock.
IDD impact
Verification
pnpm lint(npx biome check,npx dprint check,npx markdownlint-cli2— clean; only pre-existing, unrelatedwarnings elsewhere in the repo)
pnpm test(node --test tests/*.test.mts— 6212 passed, 3pre-existing skips, 0 failures)
node scripts/audit-docs.mjs --checkpnpm run docs:sync:check(clean — the template source and itsmirror stay in sync)
node scripts/idd-doctor.mjs(passed; only pre-existing,unrelated warnings)
Also ran
pnpm run build:check(generatedscripts/claim-lock.mjsmatches the committed source),
node scripts/audit-code-span-wrap.mjs,and
node scripts/token-cost-report.mjs --check(no drift).Windows CI note: the first push's "Windows platform tests" job
failed once, in
tests/idd-critique-telemetry-hook.test.mts(a win32process-kill-watchdog timing test this diff never touches). Confirmed
pre-existing: an unrelated PR (
issue/2919-...) hit the identicalfailing assertion in the same test a few hours earlier on the same
workflow. Rerun once per this repo's
ciWait.rerunPolicy.Safety
helper script's internal locking plus its documented fallback
protocol, not merge policy or gates)
.github/instructions/file touched; the touched template fileis a
docs/reference doc, not a phase-file instruction bundle)🤖 Generated with Claude Code
https://claude.ai/code/session_0164z9Kt7Ww95fre2JqidEBE
Summary by CodeRabbit
Bug Fixes
Documentation