After v0.18.0 deploy two residual issues remained on kubic.
ExpireTasks: 6 "context deadline exceeded" errors in 2.5h despite the
v0.18.0 partial index. Root cause is connection-pool contention, not
SQL speed — the tasks table is empty (steady state) and the query
plan correctly uses idx_tasks_expiry, but the worker still queues
behind the serialized write connection (MaxOpenConns=1) when another
writer holds it for >30s. Fix: add an EXISTS pre-check on the read
pool. If nothing matches, return (0, nil) without touching the write
pool. Wired via SQLiteTaskStore.WithReadDB to avoid changing the
constructor signature and disrupting tests.
Bridge: bridgeTopLevelOnly only hinted on the misspelled
rewrite_core_memory. Agents have since learned and call the real name
memory_rewrite_core via call(), which fell through to plain "unknown
action: memory_rewrite_core". Add the real name to the hint map so
both spellings get the targeted "this is a top-level MCP tool"
message.
Tests:
- ExpireTasks_EmptyShortCircuits: 0-row table returns (0, nil)
- ExpireTasks_UsesReadPoolForPreCheck: pre-check runs on read pool,
UPDATE still runs on write pool when work is present
- TopLevelToolHint: extended to cover memory_rewrite_core via bridge
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
