publicRevanth J36 days ago

Three retries with backoff in app.ts

main

2 fails · 1 recovery

duration82s

modelclaude-sonnet-4-5Claude Code 2.1.162

steps15

tool calls5

recoveries1 of 1

files2 +12 -3

categorybug fix

tokens35,980

redacted28

Execution ledger

15 steps

Prompt#109:00:02

The retry helper in app.ts gives up after the first failure. Fix it so it retries three times with backoff, then add a test.

Reasoning#209:00:05

Before touching the helper I should see the current test output, so I know whether the suite is green to begin with. Guessing at the failure mode would waste a cycle.

Response#309:00:07

I'll run the suite first to get a baseline, then change the retry helper.

Tool#4Bashnpm test --silent09:00:09

input 3 field(s)

command: npm test --silent
timeout: 120000
description: Run the test suite for a baseline

output 70 chars

Test Suites: 3 passed, 3 total
Tests: 11 passed, 11 total
Time: 4.12 s

Result#5Bashnpm test --silent09:00:22

Test Suites: 3 passed, 3 total
Tests: 11 passed, 11 total
Time: 4.12 s

input 3 field(s)

command: npm test --silent
timeout: 120000
description: Run the test suite for a baseline

Tool#6Edit/Users/«REDACTED:user»/project/app.ts09:00:26

/Users/«REDACTED:user»/project/app.ts+12 -3

-async function withRetry(fn) {
-  return fn();
-}
1+async function withRetry(fn, attempts = 3) {
2+  let lastError;
3+  for (let i = 0; i < attempts; i++) {
4+    try {
5+      return await fn();
6+    } catch (error) {
7+      lastError = error;
8+      await sleep(2 ** i * 100);
9+    }
10+  }
11+  throw lastError;
12+}

input 3 field(s)

file_path: /Users/«REDACTED:user»/project/app.ts
new_string: async function withRetry(fn, attempts = 3) { let lastError; for (let i = 0; i < attempts; i++) { try { return await fn(); } catch (error) { lastError = error; await sleep(2 ** i * 100); } } throw lastError; }
old_string: async function withRetry(fn) { return fn(); }

output 64 chars

The file /Users/«REDACTED:user»/project/app.ts has been updated.

Result#7Edit/Users/«REDACTED:user»/project/app.ts09:00:28

The file /Users/«REDACTED:user»/project/app.ts has been updated.

input 3 field(s)

file_path: /Users/«REDACTED:user»/project/app.ts
new_string: async function withRetry(fn, attempts = 3) { let lastError; for (let i = 0; i < attempts; i++) { try { return await fn(); } catch (error) { lastError = error; await sleep(2 ** i * 100); } } throw lastError; }
old_string: async function withRetry(fn) { return fn(); }

Prompt#809:00:28

Good. Now add the test in a new file rather than editing the existing suite.

Tool#9Write/Users/«REDACTED:user»/project/app.retry.test.ts09:00:33

input 2 field(s)

content: import { test } from "node:test"; import assert from "node:assert"; import { withRetry } from "./app.ts"; test("withRetry retries three times", async () => { let calls = 0; const result = await withRetry(async () => { calls += 1; if (calls < 3) throw new Error("flaky"); return "ok"; }); assert.equal(result, "ok"); assert.equal(calls, 3); });
file_path: /Users/«REDACTED:user»/project/app.retry.test.ts

output 82 chars · error

EACCES: permission denied, open '/Users/«REDACTED:user»/project/app.retry.test.ts'

Self-correction loopWrite failedstep 10 → 13

What broke

Failed#10Write/Users/«REDACTED:user»/project/app.retry.test.ts09:00:36

EACCES: permission denied, open '/Users/«REDACTED:user»/project/app.retry.test.ts'

input 2 field(s)

content: import { test } from "node:test"; import assert from "node:assert"; import { withRetry } from "./app.ts"; test("withRetry retries three times", async () => { let calls = 0; const result = await withRetry(async () => { calls += 1; if (calls < 3) throw new Error("flaky"); return "ok"; }); assert.equal(result, "ok"); assert.equal(calls, 3); });
file_path: /Users/«REDACTED:user»/project/app.retry.test.ts

Recovered by the agent

Recovered: Write ran cleanly 3 step(s) later.

Tool#11TaskCheck directory permissions09:00:41

input 3 field(s)

prompt: Find out which directory under /Users/«REDACTED:user»/project is not writable and report back.
description: Check directory permissions
subagent_type: general-purpose

output 126 chars

The project root is read-only for the current user. Tests belong under /Users/«REDACTED:user»/project/test, which is writable.

Result#12TaskCheck directory permissions09:01:05

The project root is read-only for the current user. Tests belong under /Users/«REDACTED:user»/project/test, which is writable.

input 3 field(s)

prompt: Find out which directory under /Users/«REDACTED:user»/project is not writable and report back.
description: Check directory permissions
subagent_type: general-purpose

Tool#13Write/Users/«REDACTED:user»/project/test/app.retry.test.ts09:01:09

input 2 field(s)

content: import { test } from "node:test"; import assert from "node:assert"; import { withRetry } from "../app.ts"; test("withRetry retries three times", async () => { let calls = 0; const result = await withRetry(async () => { calls += 1; if (calls < 3) throw new Error("flaky"); return "ok"; }); assert.equal(result, "ok"); assert.equal(calls, 3); });
file_path: /Users/«REDACTED:user»/project/test/app.retry.test.ts

output 82 chars

File created successfully at /Users/«REDACTED:user»/project/test/app.retry.test.ts

Result#14Write/Users/«REDACTED:user»/project/test/app.retry.test.ts09:01:12

File created successfully at /Users/«REDACTED:user»/project/test/app.retry.test.ts

input 2 field(s)

content: import { test } from "node:test"; import assert from "node:assert"; import { withRetry } from "../app.ts"; test("withRetry retries three times", async () => { let calls = 0; const result = await withRetry(async () => { calls += 1; if (calls < 3) throw new Error("flaky"); return "ok"; }); assert.equal(result, "ok"); assert.equal(calls, 3); });
file_path: /Users/«REDACTED:user»/project/test/app.retry.test.ts

Response#1509:01:24

Done. withRetry now makes three attempts with exponential backoff, and test/app.retry.test.ts covers the retry path. The project root is read-only, so the test went under test/ instead.

Brief

What this run was asked, what blocked it, and what it left. Every quote is the run’s own text.

Asked

The retry helper in app.ts gives up after the first failure. Fix it so it retries three times with backoff, then add a test.

Steered 1

step 7 · after Edit app.ts

Good. Now add the test in a new file rather than editing the existing suite.

Blockers and fixes 1

Write app.retry.test.ts failed

EACCES: permission denied, open 'app.retry.test.ts'

Checked Task: Check directory permissions: “The project root is read-only for the current user. Tests belong under test, which is writable.”
Fixed by Write test/app.retry.test.ts

Verification

npm test --silent passed before the first edit (3 suites, 11 tests)

Not re-run after the last edit.

Files 2

app.ts +12 −3
test/app.retry.test.ts created

Git

branch: main

Diagnostics

steps: 15: 13 by the agent, 2 prompts from a person
tool calls: 5
failures: 1, 1 recovery by the agent
tokens: in 20,592 · out 1,288 · cache read 12,000 · cache write 2,100

Context capsule

The brief as markdown, for another agent’s context.

Context capsule · flatbread.io/r/mfs0r779
Claude Code · claude-sonnet-4-5-20250929 · 15 steps · app.ts +12 / −3 · test/app.retry.test.ts created
Git: branch main

Asked:
> The retry helper in app.ts gives up after the first failure. Fix it so it retries three times with backoff, then add a test.

Steered:
- "Good. Now add the test in a new file rather than editing the existing suite."

Blocker and fix (do not repeat):
- Write app.retry.test.ts failed: EACCES: permission denied, open 'app.retry.test.ts'
- Checked (Task: Check directory permissions): "The project root is read-only for the current user. Tests belong under test, which is writable."
- Fixed by: Write test/app.retry.test.ts

Verification: npm test --silent passed before the first edit (3 suites, 11 tests). Not re-run after the last edit.

Diff (app.ts):
-async function withRetry(fn) {
-  return fn();
-}
+async function withRetry(fn, attempts = 3) {
+  let lastError;
+  for (let i = 0; i < attempts; i++) {
+    try {
+      return await fn();
+    } catch (error) {
+      lastError = error;
+      await sleep(2 ** i * 100);
+    }
+  }
+  throw lastError;
+}

Pull it from a terminal

flatbread pull mfs0r779

Install the command once with npm install -g flatbread-cli. Or let your coding agent search runs and pull capsules itself: claude mcp add flatbread -- flatbread mcp. A private run pulls for its owner after flatbread login, or through its share link.