Claude Code vs DeepSeek Harness — DeepSeek Harness vs Claude Code: 2 side-by-side tests
2 posts from X ran Claude Code and DeepSeek Harness on the same task, between Oct 19, 2026 and Oct 19, 2026. Models: Claude Fable 5.1, GPT-6 Astra, DeepSeek V4.1 Flash 1017, Claude Opus 5.5, GPT-6.1 Sol, DeepSeek V4 Pro 0813. All harness comparisons.
- 2 posts state a time for both, split evenly (Claude Code 1, DeepSeek Harness 1).
- 1 post states a cost for both: DeepSeek Harness was cheaper in it, by ~15×.
- None keeps the model fixed: each side ran its own model, so harness and model effects are mixed — not a controlled comparison.
From 2 posts; costs and times as stated by each author, not a controlled benchmark.
Posts
2
Claude Code vs DeepSeek Harness, test by test
| Test | Claude Code: model | DeepSeek Harness: model | Time (Claude Code / DeepSeek Harness) | Cost (Claude Code / DeepSeek Harness) | Author’s pick |
|---|---|---|---|---|---|
| Three.js night scene in three labs’ agents@agentsky_dev | Claude Fable 5.1 | DeepSeek V4.1 Flash 1017 | 4.9 min / 22.7 min | $2.05 / $0.14 | — |
| Tetris in three agents: Claude Code, Codex, DeepSeek@agentsky_dev | Claude Opus 5.5 | DeepSeek V4 Pro 0813 | 4 min / 3.4 min | — | — |
Numbers are as each post states them; “—” means the post gives none. Tests and models differ from row to row.
Claude Code vs DeepSeek Harness pricing: plans
From each vendor’s official pricing page (checked 2026-10-19); prices exclude tax and can change. Usage limits differ by plan and model.
API list prices of the models in these tests
| Model | Used with | Input $/1M tokens | Output $/1M tokens |
|---|---|---|---|
| Claude Fable 5.1 | Claude Code | ||
| Claude Opus 5.5 | Claude Code | $4 | $20 |
| DeepSeek V4.1 Flash 1017 | DeepSeek Harness | $0.30peak hours; off-peak is half price | $1.20peak hours; off-peak is half price |
| DeepSeek V4 Pro 0813 | DeepSeek Harness |
Official API list prices where verified; a blank cell has no verified official price in the archive (older or retired models).
What each test showed
In every test below each side ran its own model, so these are not controlled comparisons of the harnesses alone.
Three.js night scene in three labs’ agents — Claude Fable 5.1 in Claude Code vs DeepSeek V4.1 Flash 1017 in DeepSeek Harness
Same three.js night scene, one run each: Claude Code with Claude Fable 5.1 (4:54, $2.05), Codex with GPT-6 Astra (1:52, $0.55) and DeepSeek Harness with DeepSeek V4.1 Flash 1017 (22:42, $0.14). The post also includes OpenAI Codex.
- Claude Code with Claude Fable 5.1: time 4.9 min, cost $2.05.
- OpenAI Codex with GPT-6 Astra: time 112 s, cost $0.55.
- DeepSeek Harness with DeepSeek V4.1 Flash 1017: time 22.7 min, cost $0.14 — Cheapest, slowest by far.
As stated: Claude Code 4:54, $2.05; Codex 1:52, $0.55; DeepSeek Harness 22:42, $0.14.
Posted Oct 19, 2026 by AgentSky (@agentsky_dev). Original post on X · Video and details
Tetris in three agents: Claude Code, Codex, DeepSeek — Claude Opus 5.5 in Claude Code vs DeepSeek V4 Pro 0813 in DeepSeek Harness
Same Tetris prompt in three agents: Claude Code with Claude Opus 5.5 (3:58, $0.60), Codex with GPT-6.1 Sol (3:25, $0.16) and DeepSeek Harness with DeepSeek V4 Pro (3:24, $0.26). All three games are playable. The post also includes OpenAI Codex.
- Claude Code with Claude Opus 5.5: time 4 min — Playable; its AI clears lines.
- OpenAI Codex with GPT-6.1 Sol: time 3.4 min — Playable; cheapest of the three.
- DeepSeek Harness with DeepSeek V4 Pro 0813: time 3.4 min — Playable, but its turn ended mid self-test.
As stated: Claude Code 3:58, $0.60; Codex 3:25, $0.16; DeepSeek Harness 3:24, $0.26.
Posted Oct 19, 2026 by AgentSky (@agentsky_dev). Original post on X · Video and details
Claude Code vs DeepSeek Harness (DeepSeek Harness vs Claude Code): FAQ
Is Claude Code better than DeepSeek Harness?
None of the 2 posts names a winner between the two.
Which is faster, Claude Code or DeepSeek Harness?
Neither, going by the posts' own numbers: the 2 posts that give a time for each side come out even (Claude Code 1, DeepSeek Harness 1). Times are as each author states them; models and settings differ.
Which is cheaper, Claude Code or DeepSeek Harness?
DeepSeek Harness, going by the posts' own numbers: it was cheaper in the one post that gives a cost for each side (by ~15×). Those are the run costs the posts state. Claude Code plans (official pricing page, checked 2026-10-19): Free Not included, Pro $20/month, Max From $100/month, API (Console) Pay as you go.
Which models were used with Claude Code and DeepSeek Harness?
With Claude Code: Claude Fable 5.1, Claude Opus 5.5. With DeepSeek Harness: DeepSeek V4.1 Flash 1017, DeepSeek V4 Pro 0813.