2 min lesson

Investigate a retry bug in parallel

Run two read-only surveys in parallel, inspect both reports and keep the edit in the parent task.

Check your understanding

Complete the practice "Retry bug split into two read-only lanes".

Outcome: Both subagents remained read-only. The final diff contains only the parent change and test. Each claim links to evidence you opened.

Retry bug split into two read-only lanes

Explore and .cursor/agents/retry-test-map.md

SayBefore editing the retry bug, I need two reports: every retry value, and current test coverage with missing failure paths. Neither lane may edit.

DoKeep implementation in the parent task. Give each clean context the api-client package, symptom and exact return format.

Type

---
name: retry-test-map
description: Map retry test coverage and missing failure cases. Use when a retry change needs a coverage report.
readonly: true
is_background: true
---

DoCreate .cursor/agents/retry-test-map.md. In its prompt body, require test file, case name, covered path and missing case for each result.

SeeThe project subagent is read-only and can run in the background while the other survey works.

Type

Run Explore and /retry-test-map in parallel. Explore src/api-client for retry and backoff values. Return file, symbol, value and caller. Do not edit. Inspect src/api-client/__tests__ for the required coverage table.

DoLaunch both bounded surveys together. Use Explore for the code search and the custom subagent for coverage.

SeeIntermediate search and test output stays in each subagent context. The parent receives two small reports instead of every command and file read.

DoOpen every cited symbol and test case in the parent task. Resolve disagreements before touching the retry code.

SeeThe config report finds three values. The test report confirms timeout and 503 coverage, and identifies the missing rate-limit case.

DoMake the one retry edit in the parent task, add the missing test and inspect the full diff.

SeeBoth subagents remained read-only. The final diff contains only the parent change and test. Each claim links to evidence you opened.

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Optional practice

Test yourself on Investigate a retry bug in parallel

QWhich result proves the retry investigation was delegated safely?