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
Latest recipes
All recipes →- Verified
3 of 3runs passed every hidden test either way; only 'think hard' runs added and ran tests (3 of 3 vs 0 of 3)
Does 'think hard' actually help? Same pass rate, but it tested its own work
We asked Claude Code to implement a billing-date function full of edge cases six times. Three runs got the plain request, three also got "Think hard about this before you write any code." All six passed every hidden test. Only the think-hard runs added tests and ran them, for about 60% more per run.
- Verified
2 of 3runs fully fixed the bug with the stack trace pasted (0 of 3 with a description)
Paste the error, or describe it? Both found the bug; only pasted errors caught the second crash
We gave Claude Code the same crashing notes API six times. Three runs got a one-line description of the symptom, three also got the stack trace. All six found the root cause. Only the pasted-error runs also fixed a second crash in tag counts, in 2 of 3 runs, for about half a cent more per run.
- Verified
4,271 → 522tokens the setup added to every session, before and after the audit
We had Claude Code audit a bloated setup. It cut 88% of what the setup loaded.
A 1,500-word CLAUDE.md and 8 skills added about 4,300 tokens to every session. After an audit, the setup added about 500 tokens and every rule still held. That was a cut of around 16% of startup context, not most of it.
- Local-model test
15 vs 18 of 18runs passed, local Qwen 27B (thinking on) vs Sonnet 5.5 (adaptive)
A 27B model on two home AMD cards passed 15 of 18. Sonnet passed 18.
We ran Qwen3.8-27B on two Radeon AI PRO R9700s against Claude Sonnet 5.5 and Haiku 5.5 on six auto-graded tasks. Sonnet with thinking passed all 18 runs for $0.30. Qwen with thinking passed 15 for $0 in API, and most of its git patches didn't apply.
- Verified
73% morecost per run with plan mode first (6 of 6 passed either way)
Plan mode first, or just start? Both passed; planning cost 73% more
We asked Claude Code to add note archiving to a 24-file API six times. Three runs planned first in plan mode, three just started. All six passed our hidden tests. Planning first cost about 73% more per run, $0.28 against $0.16.
- Verified
3 of 3runs passed the hidden edge-case test with tests first (2 of 3 without)
Ask for tests first: 3 runs with, 3 without
We asked Claude Code for a bill-splitting function six times. Asked plainly, it shipped a rounding bug in 1 of 3 runs. Told to write failing tests first, 3 of 3 passed our hidden edge-case test, for about 2 cents more per run.