Official run
Claude Fable 5.1High
In this Twenty Questions AI benchmark, Claude Fable 5.1 (high) ranks 2 of 18 with a question score of 12.11: the average number of questions per round, where lower is better. It failed 1 of 35 rounds. The run has 35 scored rounds: 7 subjects, 5 rounds each. Choose a subject to see its rounds.
Rank 2 of 18anthropicHigh
Round scores are averaged for each subject, then across subjects. A failed round gets the fixed failure score.
The 95% confidence interval shows how certain the average is, based on repeated rounds on these subjects. A wider interval means less consistent results. It does not predict scores on other subjects.
- Solved
- 97%
- Valid format
- 99.8%
- Guesser cost
- $17.55
- Guesser time
- 1h 55m
Drill down
Subjects.
Complete benchmark
Run totals.
Includes the Guesser and all answer-checking models.
- Total tokens
- 5,592,470
- Total runtime
- 3h 24m
- Guesser calls
- 458
- Completed
Reply format
Format errors found.
1 invalid reply in 1 round used up 1 counted turn.
Run details
- Execution
BX-20260902-official-M0020-001- Model ID
M-0020- Benchmark
B-0001- Base seed
0- Git commit
47e9bc269762
Recorded cost
By role.
- Guesser74.3%$17.55
- Oracle20%$4.71
- Reviewer2%$0.48
- Judge3.7%$0.86
- Validator0%$0.01
Roles in this cost:
- Guesser
- The tested model. Asks questions and makes guesses.
- Oracle
- Searches for evidence and proposes an answer.
- Reviewer
- Checks each Oracle answer except Unknown, without seeing it.
- Judge
- Decides when the Oracle and Reviewer disagree.
- Validator
- Checks whether a guess names the hidden subject.
Run configuration
Models.
Models, prompt versions, providers, calls, and cost for the whole run.
anthropic/claude-fable-5.1
The tested model. Asks questions and makes guesses.
- Calls
- 458
- Cost
- $17.5485
- Reasoning
- High
- Routing
- Fixed provider · anthropic
- Resolved model
- anthropic/claude-fable-5.1
- Resolved provider
- Anthropic
- Prompt version
stateful-category-guesser-v10-unknown-evidence-guidance- Configuration
M-0020
Provider details
- Fallback calls
- 0
- Provider not reported
- 0
Answer checks
Answering and checking models.
These models answer and check the Guesser's questions and guesses. They are the same for every round and are not being tested.
openai/gpt-5.6-luna
Searches for evidence and proposes an answer.
- Calls
- 392
- Cost
- $4.7148
- Reasoning
- Medium
- Routing
- Fixed provider · openai
- Resolved model
- openai/gpt-5.6-luna
- Resolved provider
- OpenAI
- Prompt version
live-web-oracle-v8-classified-research
Provider details
- Fallback calls
- 0
- Provider not reported
- 0
google/gemini-3.5-flash-lite
Checks each Oracle answer except Unknown, without seeing it.
- Calls
- 386
- Cost
- $0.4783
- Reasoning
- Medium
- Routing
- Fixed provider · google-ai-studio
- Resolved provider
- Google AI Studio
Provider details
- Fallback calls
- 0
- Provider not reported
- 0
anthropic/claude-opus-5
Decides when the Oracle and Reviewer disagree.
- Calls
- 70
- Cost
- $0.8632
- Reasoning
- Medium
- Routing
- Chosen automatically by OpenRouter
- Resolved provider
- Claude Platform on AWS
Provider details
- Fallback calls
- 0
- Provider not reported
- 0
openai/gpt-5.6-luna
Checks whether a guess names the hidden subject.
- Calls
- 65
- Cost
- $0.0088
- Reasoning
- Medium
- Routing
- Fixed provider · openai
- Resolved model
- openai/gpt-5.6-luna
- Resolved provider
- OpenAI
- Prompt version
strict-guess-validator-v1- Configuration
gpt-5.6-luna-validator
Provider details
- Fallback calls
- 0
- Provider not reported
- 0