Claude Fable 5
Anthropic's most powerful, most intelligent model — a tier above Opus. Adaptive thinking; the model that built this site.
- name
- Claude Fable 5
- vendor
- Anthropic
- model_id
- claude-fable-5
- context_window
- 1M
- max_output
- 128K
- input_per_mtok
- $10.00
- output_per_mtok
- $50.00
- strengths
- Anthropic's most powerful, most intelligent model — a tier above Opus. Adaptive thinking; the model that built this site.
- provider
- Anthropic
- family
- Claude Fable
- release_date
- 2026-06-09 source
- last_updated
- 2026-06-15
- open_weights
- false source
- license
- proprietary source
- params_total
- — verify-against-primary-at-build ↗ https://www.anthropic.com/news/claude-fable-5-mythos-5 (Anthropic does not disclose parameter counts)
- params_active
- — verify-against-primary-at-build ↗ https://www.anthropic.com/news/claude-fable-5-mythos-5 (Anthropic does not disclose parameter counts)
- tool_call
- true source
- reasoning
- always source
- structured_output
- — verify-against-primary-at-build ↗ https://platform.claude.com/docs/en/about-claude/models/overview — schema-guaranteed structured-output flag not explicitly published for claude-fable-5 (no models.dev entry exists for this model).
- attachment
- image source
- temperature
- — verify-against-primary-at-build ↗ https://platform.claude.com/docs/en/about-claude/models/overview — temperature-control flag not explicitly stated for claude-fable-5.
- knowledge_cutoff
- — verify-against-primary-at-build ↗ https://platform.claude.com/docs/en/about-claude/models/overview — reliable knowledge / training cutoff not published in the Fable 5 / Mythos 5 launch table.
- context_advertised
- 1M source
- context_effective
- — verify-against-primary-at-build ↗ No published measured long-context recall benchmark for claude-fable-5; do not derive effective context from advertised.
- price_input
- $10.00 source
- price_output
- $50.00 source
- price_cache_read
- — verify-against-primary-at-build ↗ https://platform.claude.com/docs/en/about-claude/pricing — cache-read rate for claude-fable-5 not captured numerically in fetched sources.
- price_cache_write
- — verify-against-primary-at-build ↗ https://platform.claude.com/docs/en/about-claude/pricing — cache-write rate for claude-fable-5 not captured numerically in fetched sources.
- cost_per_full_window
- — verify-against-primary-at-build ↗ Derived at build from price_input × advertised context once both are confirmed.
- cost_per_agent_task
- — verify-against-primary-at-build ↗ Derived at build from the cache-aware agent-task model once cache rates are confirmed.
- modalities
- text-in,image-in,text-out source
- gpqa_diamond
- — verify-against-primary-at-build ↗ https://www.anthropic.com/news/claude-fable-5-mythos-5 — benchmark numbers not captured from a primary leaderboard in this pass.
- swe_bench_verified
- — verify-against-primary-at-build ↗ https://www.anthropic.com/news/claude-fable-5-mythos-5 — SWE-bench Verified score not captured from a primary source in this pass.
- terminal_bench
- — verify-against-primary-at-build ↗ https://www.tbench.ai/ — Terminal-Bench score for claude-fable-5 to confirm at build.
- tau2_bench
- — verify-against-primary-at-build ↗ Primary τ²-Bench leaderboard — score for claude-fable-5 to confirm at build.
- bfcl_tool_use
- — verify-against-primary-at-build ↗ https://gorilla.cs.berkeley.edu/leaderboard.html — BFCL tool-use score for claude-fable-5 to confirm at build.
- aa_index
- — verify-against-primary-at-build ↗ https://artificialanalysis.ai/ — Intelligence Index for claude-fable-5 to confirm at build.
- lmarena_elo
- — verify-against-primary-at-build ↗ https://lmarena.ai/leaderboard — human-preference Elo for claude-fable-5 to confirm at build.
- tokens_per_sec
- — verify-against-primary-at-build ↗ https://artificialanalysis.ai/ — measured throughput for claude-fable-5 to confirm at build.
- ttft
- — verify-against-primary-at-build ↗ https://artificialanalysis.ai/ — measured time-to-first-token for claude-fable-5 to confirm at build.
- hallucination_rate
- — verify-against-primary-at-build ↗ No primary hallucination benchmark captured for claude-fable-5 in this pass.
- agent_readiness_score
- — verify-against-primary-at-build ↗ Score withheld: R_tool (BFCL/τ²-Bench), R_ctx (effective context), R_cost (cache rates) and R_latency inputs are not yet sourced. Compute per /models/agent-readiness-score once inputs confirmed.
- score_confidence
- partial
- source_url
- https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5
- source_type
- provider_card
- last_verified
- 2026-06-15