168 runs on record · last run 11 Nov 2026
Claude Code tips, run before they ship.
Every recipe here was run in a real Claude Code session first. The cost, the diff and the pass or fail of each check are published next to the advice, and re-tested when Claude Code updates.
| Model | All checks | Avg cost | Avg time |
|---|---|---|---|
| Haiku | 3 of 3 | $0.009 | 28s |
| Sonnet | 3 of 3 | $0.105 | 27s |
| Opus | 3 of 3 | $0.221 | 42s |
Claude Code 2.1.296 · 13 Oct 2026 · full run data
- Write-ups published
- 23
- Runs on record
- 168
- Spent on those runs
- $46.57
- Newest Claude Code tested
- 2.1.321
Latest recipes
All 23 recipes →- Verified
$0.148 → $0.082per 3-task sequence: full CLAUDE.md in fresh sessions vs trimmed CLAUDE.md in one continued session
Does Claude Code cache your startup context? Yes, but fresh sessions pay for CLAUDE.md again
We ran the same 3 small tasks with a 1,501-word or a 9-line CLAUDE.md, in fresh sessions or one continued session, 3 runs each, and logged cache reads and writes on every API request. Every run's first request read the same 13,069 tokens from cache and sent 2 uncached. CLAUDE.md was another story: fresh sessions wrote it to cache again for each task. Trimming cut cost 20 to 22%; staying in one session cut 29 to 31%; both together, 45%.
- Verified
$2.64 vs $3.28average cost per run, Fable 5.2 (Claude Code 2.1.321 rerun) vs Fable 5.1 (both fixed the bug in every scored run)
Fable 5.2 is 20% cheaper per token. On our bug fix it averaged $2.64 a run, under Fable 5.1's $3.28
Launch-day test: Claude Fable 5.2, Fable 5.1 and Opus 5.5 on the same planted bug in undici (902 files), same prompt and tools. Fable 5.2 (rerun on Claude Code 2.1.321) fixed the bug in 3 of 3 and averaged $2.64 a run and 2.37M tokens. Fable 5.1 averaged $3.28 and 2.04M; Opus $0.77 and 1.39M. Small samples: 3, 2 and 3 runs.
- Verified
3 of 3 eachruns kept SAVE10 coverage and caught a 9% mutation; $0.013 a run for Haiku 5.5, $0.117 for Sonnet 5.5
Test cleanup is the job everyone wants to hand off. Can the cheap model do it without quietly deleting coverage?
We gave Sonnet 5.5 and Haiku 5.5 the same messy test suite: duplicates, skips, a dead import, and one precise SAVE10 assertion that looks redundant. Both kept the coverage and caught a SAVE10→9% mutation in 3 of 3 runs. Haiku averaged $0.013 a run; Sonnet $0.117, about 9× more.
- Verified
0 of 15runs that started a subagent, on a 902-file repo (all 15 fixed the bug)
We gave Opus a 902-file repo and a search-heavy bug. It started 0 subagents in 15 runs
A follower said our last task was too small for Opus to delegate. So we used undici, Node's HTTP client (902 files, pinned commit), and a bug that needs tracing through 4+ files. Sonnet alone, Opus with subagents off and Opus with default subagents all fixed it in 5 of 5 runs, and none of them started a single subagent. Sonnet cost $0.248 a run; Opus $0.776 with subagents available and $0.951 without.
- Verified
$0.051 vs $0.073per run, a 9-line decisions-only CLAUDE.md vs an 84-line full description (all 9 runs avoided the trap)
Should your CLAUDE.md describe the code, or just the decisions? We tested 3 versions
Same task, same planted trap, 9 runs: no CLAUDE.md, a 9-line decisions-only file, and an 84-line full description. Sonnet avoided the trap and passed the hidden test in all 9. The decisions file was the cheapest at $0.051 a run; the full description cost $0.073, 43% more.
- Verified
$0.30API cost for Claude Code to build it: 2 prompts, 126 seconds
We had Claude Code build a cost tracker. It took 2 prompts and $0.30.
Claude Code (Sonnet 5.5) built cc-cost, a small CLI that reads its own session logs and prints API spend per day and per session. It took 2 prompts, 126 seconds and $0.30. Its tests passed the first time, but the real logs turned up an undercount the tests missed. After one fix it matched Claude Code's own cost totals on 76 of 86 real sessions.