Pick Claude Fable 5.1 for terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) or cursorbench 3.2 agentic coding (73.4%). Pick Fugu Max for cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60% or 1m-token context window at $2/$6 per million tokens. On a tight budget at scale, Fugu Max is the value pick.
Claude Fable 5.1 (Anthropic) and Fugu Max (Sakana AI) are two of the models people most often weigh against each other in 2026. Claude Fable 5.1 is anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Fugu Max is sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.
Key differences
Price: Fugu Max is about 5× cheaper on input ($2/$6 per 1M tokens vs $10/$50 per 1M tokens) — a large enough gap that at scale it can be the single biggest line item in the decision.
Context window: both advertise 1M tokens (~1,500 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
Specifications
Spec
Claude Fable 5.1
Fugu Max
Provider
Anthropic (US)
Sakana AI (Global)
Released
September 1, 2026
September 10, 2026
Context window
1M tokens (~1,500 pages)
1M tokens (~1,500 pages)
Price (in/out)
$10/$50 per 1M tokens
$2/$6 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image
text
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%): Claude Fable 5.1 — Fugu Max is comparatively weak here — not a single trained model — Sakana describes Fugu as "a Multi-Agent System, Delivered as One Model" that routes tasks across a pool of other models, so raw benchmark comparisons to monolithic models can be misleading
CursorBench 3.2 agentic coding (73.4%): Claude Fable 5.1 — Claude Fable 5.1 lists cursorBench 3.2 agentic coding (73.4%) among its strengths; Fugu Max does not.
Cache-read pricing cut to a quarter of other Claude models: Claude Fable 5.1 — Claude Fable 5.1 lists cache-read pricing cut to a quarter of other Claude models among its strengths; Fugu Max does not.
Cost-efficient multi-agent orchestration — undercuts Claude Sonnet 5 and Kimi K3 on output cost by a claimed 40-60%: Fugu Max — At $2/$6 per 1M tokens it undercuts Claude Fable 5.1 ($10/$50 per 1M tokens), and that gap compounds at volume.
1M-token context window at $2/$6 per million tokens: Fugu Max — Sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens — and it runs cheaper at $2/$6 per 1M tokens.
OpenAI-compatible API — drop-in replacement for single-model integrations: Fugu Max — Claude Fable 5.1 is comparatively weak here — anthropic has not published an official SWE-bench Verified score for this model
Lowest cost at scale: Fugu Max — At $2/$6 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Which should you pick?
A cost-sensitive startup shipping high volume: Fugu Max — At $2/$6 per 1M tokens it undercuts Claude Fable 5.1, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%): Claude Fable 5.1 — It is specifically built for that.
Anyone whose priority is cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%: Fugu Max — That is its strongest area.
Claude Fable 5.1: where it fits
Anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Released September 1, 2026 by Anthropic, it is built for terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%), cursorBench 3.2 agentic coding (73.4%), cache-read pricing cut to a quarter of other Claude models, and long, multistep, document-heavy professional work with 1M-token context.
Its trade-offs are real: anthropic has not published an official SWE-bench Verified score for this model, restricted Mythos 5.1 variant outscores it on some benchmarks due to lighter safeguards (Terminal-Bench 4.0: 60.9% vs 55.8%), and closed weights, no self-hosting option. At $10 in / $50 out per million tokens, it sits in the premium price band.
Fugu Max: where it fits
Sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens. Released September 10, 2026 by Sakana AI, it is built for cost-efficient multi-agent orchestration — undercuts Claude Sonnet 5 and Kimi K3 on output cost by a claimed 40-60%, 1M-token context window at $2/$6 per million tokens, and openAI-compatible API — drop-in replacement for single-model integrations.
Its trade-offs: not a single trained model — Sakana describes Fugu as "a Multi-Agent System, Delivered as One Model" that routes tasks across a pool of other models, so raw benchmark comparisons to monolithic models can be misleading, the cheaper sibling to Fugu Ultra v2 — lower ceiling on the hardest reasoning tasks, and a young, first-generation product from Sakana AI's orchestration approach, unproven at scale versus established frontier labs. At $2 in / $6 out per million tokens, it sits in the mid price band.
The bottom line for this matchup
Claude Fable 5.1 and Fugu Max overlap enough that the right pick depends on your specific job. Fugu Max costs less per token; and each leads in its own area — Claude Fable 5.1 for terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%), Fugu Max for cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%. Rather than crowning one, run the same hard task through both once and let the results decide.
Frequently asked questions
Is Claude Fable 5.1 or Fugu Max better for coding?
Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Claude Fable 5.1 leans toward terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) while Fugu Max leans toward cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Fable 5.1 or Fugu Max?
Fugu Max is cheaper — $10/$50 per 1M tokens vs $2/$6 per 1M tokens, roughly 5× apart on input.
Which has the bigger context window?
Both advertise 1M tokens (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.
Can I use both Claude Fable 5.1 and Fugu Max together?
Yes — a multi-model platform like LumiChats gives you Claude Fable 5.1, Fugu Max and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.
Which is newer, Claude Fable 5.1 or Fugu Max?
Fugu Max — released September 10, 2026, about 9 days after Claude Fable 5.1.
Claude Fable 5.1 vs Fugu Max
Anthropic · US | Sakana AI · Global · Updated June 2026
Quick verdict
Pick Claude Fable 5.1 for terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) or cursorbench 3.2 agentic coding (73.4%). Pick Fugu Max for cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60% or 1m-token context window at $2/$6 per million tokens. On a tight budget at scale, Fugu Max is the value pick.
Claude Fable 5.1 (Anthropic) and Fugu Max (Sakana AI) are two of the models people most often weigh against each other in 2026. Claude Fable 5.1 is anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Fugu Max is sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.
Key differences at a glance
▸Price: Fugu Max is about 5× cheaper on input ($2/$6 per 1M tokens vs $10/$50 per 1M tokens) — a large enough gap that at scale it can be the single biggest line item in the decision.
▸Context window: both advertise 1M tokens (~1,500 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
Side-by-side specs
Spec
Claude Fable 5.1
Fugu Max
Provider
Anthropic (US)
Sakana AI (Global)
Released
September 1, 2026
September 10, 2026
Context window
1M tokens (~1,500 pages)
1M tokens (~1,500 pages)
Price (in/out)
$10/$50 per 1M tokens
$2/$6 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image
text
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
Not published
Not published
Who wins what
Terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%)
Claude Fable 5.1
Fugu Max is comparatively weak here — not a single trained model — Sakana describes Fugu as "a Multi-Agent System, Delivered as One Model" that routes tasks across a pool of other models, so raw benchmark comparisons to monolithic models can be misleading
CursorBench 3.2 agentic coding (73.4%)
Claude Fable 5.1
Claude Fable 5.1 lists cursorBench 3.2 agentic coding (73.4%) among its strengths; Fugu Max does not.
Cache-read pricing cut to a quarter of other Claude models
Claude Fable 5.1
Claude Fable 5.1 lists cache-read pricing cut to a quarter of other Claude models among its strengths; Fugu Max does not.
Cost-efficient multi-agent orchestration — undercuts Claude Sonnet 5 and Kimi K3 on output cost by a claimed 40-60%
Fugu Max
At $2/$6 per 1M tokens it undercuts Claude Fable 5.1 ($10/$50 per 1M tokens), and that gap compounds at volume.
1M-token context window at $2/$6 per million tokens
Fugu Max
Sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens — and it runs cheaper at $2/$6 per 1M tokens.
OpenAI-compatible API — drop-in replacement for single-model integrations
Fugu Max
Claude Fable 5.1 is comparatively weak here — anthropic has not published an official SWE-bench Verified score for this model
Lowest cost at scale
Fugu Max
At $2/$6 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Which should you pick?
A cost-sensitive startup shipping high volume
→ Fugu Max
At $2/$6 per 1M tokens it undercuts Claude Fable 5.1, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%)
→ Claude Fable 5.1
It is specifically built for that.
Anyone whose priority is cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%
→ Fugu Max
That is its strongest area.
Claude Fable 5.1: where it fits
Anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Released September 1, 2026 by Anthropic, it is built for terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%), cursorBench 3.2 agentic coding (73.4%), cache-read pricing cut to a quarter of other Claude models, and long, multistep, document-heavy professional work with 1M-token context.
Its trade-offs are real: anthropic has not published an official SWE-bench Verified score for this model, restricted Mythos 5.1 variant outscores it on some benchmarks due to lighter safeguards (Terminal-Bench 4.0: 60.9% vs 55.8%), and closed weights, no self-hosting option. At $10 in / $50 out per million tokens, it sits in the premium price band.
Fugu Max: where it fits
Sakana AI's cost-first multi-agent orchestration model — not a single trained model, but a routed pool of models behind one API, priced at $2/$6 per million tokens. Released September 10, 2026 by Sakana AI, it is built for cost-efficient multi-agent orchestration — undercuts Claude Sonnet 5 and Kimi K3 on output cost by a claimed 40-60%, 1M-token context window at $2/$6 per million tokens, and openAI-compatible API — drop-in replacement for single-model integrations.
Its trade-offs: not a single trained model — Sakana describes Fugu as "a Multi-Agent System, Delivered as One Model" that routes tasks across a pool of other models, so raw benchmark comparisons to monolithic models can be misleading, the cheaper sibling to Fugu Ultra v2 — lower ceiling on the hardest reasoning tasks, and a young, first-generation product from Sakana AI's orchestration approach, unproven at scale versus established frontier labs. At $2 in / $6 out per million tokens, it sits in the mid price band.
The bottom line for this matchup
Claude Fable 5.1 and Fugu Max overlap enough that the right pick depends on your specific job. Fugu Max costs less per token; and each leads in its own area — Claude Fable 5.1 for terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%), Fugu Max for cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%. Rather than crowning one, run the same hard task through both once and let the results decide.
Want both Claude Fable 5.1 and Fugu Max without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.
Is Claude Fable 5.1 or Fugu Max better for coding?
Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Claude Fable 5.1 leans toward terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) while Fugu Max leans toward cost-efficient multi-agent orchestration — undercuts claude sonnet 5 and kimi k3 on output cost by a claimed 40-60%, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Fable 5.1 or Fugu Max?
Fugu Max is cheaper — $10/$50 per 1M tokens vs $2/$6 per 1M tokens, roughly 5× apart on input.
Which has the bigger context window?
Both advertise 1M tokens (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.
Can I use both Claude Fable 5.1 and Fugu Max together?
Yes — a multi-model platform like LumiChats gives you Claude Fable 5.1, Fugu Max and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.
Which is newer, Claude Fable 5.1 or Fugu Max?
Fugu Max — released September 10, 2026, about 9 days after Claude Fable 5.1.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.