You are the Guesser being evaluated in a Twenty Questions benchmark. One subject is hidden. The initial BEGIN message provides its broad category as trusted game metadata. Identify the subject using as few counted questions as possible. ASK is only for learning a property that helps distinguish possible candidates. Never use ASK to confirm a named candidate or ask whether the subject is a specific identity. When you are ready to name a candidate, use GUESS immediately. A correct GUESS costs zero counted questions; an incorrect GUESS costs exactly one, the same as ASK. A GUESS must provide both a name and a short identifying description. The engine replies only YES, NO, or UNKNOWN; UNKNOWN is a valid answer meaning the factual adjudication system could not determine the proposition under its evidence policy. Questions requiring proof of absence, exclusivity, completeness, exact counts, or subjective classification are more likely to return UNKNOWN. Prefer direct, positively verifiable properties when possible. The initial BEGIN event includes an opaque variation_token that contains no information about the hidden subject. Do not interpret, repeat, mention, or derive meaning from it. After BEGIN, each user reply is either one adjudicated YES, NO, or UNKNOWN token or a fixed FORMAT_ERROR event. FORMAT_ERROR means your immediately preceding response did not match the required structured-action contract, was not semantically adjudicated, and consumed one counted turn. Use the formats in that event and try again. Never infer that the attempted question or guess was right or wrong. At most 50 questions or rejected guesses are counted. After that limit you receive one final guess-only opportunity. Format errors also consume counted turns. The provider wire response is an object with exactly one `result` action. On the final opportunity ASK is forbidden. Return only the required structured response. Do not include analysis, hidden reasoning, or additional fields.
- Questions
- 9
- Outcome
- Solved
- Format errors
- Errors found View one example
- Duration
- 1m 44s
- Round cost
- $0.0867 All 10 turns
Format warning
The model sent replies in the wrong format.
The Guesser sent 1 invalid reply. Each one before the question limit used up a counted turn. The model was only reminded of the required format; it was never told whether its question or guess was correct.
- Valid format
- 90.0%
- Format errors
- 1
- Turns used by format errors
- 1
Transcript
Questions and answers.
Turns are shown in the order they happened. Each shows the Guesser's question or guess, then the final checked answer.
Exact Guesser setupSystem message and BEGIN event
The Guesser received these messages at the start of the round. The BEGIN message holds the broad category and a code made from the base seed and round number, which reveals nothing about the subject.
{"category":"mythological_figure","event":"BEGIN","variation_token":"BYOMPCJW"}Valid replies are shown in the required format. Rejected replies are shown separately, without provider or call IDs.
Reply in the wrong format.
Invalid action · fixed format reminder sent
Why this reply was rejectedInvalid action · turn 1
The reply was JSON, but it matched neither the ASK nor the GUESS format.
- Recorded type
invalid_action- Turn
- 1
- Counted
- Yes · question 1
- Feedback
- FORMAT_ERROR
{"action":"ASK","value":"Is this figure from Greek mythology?"}{"result":{"action":"ASK","description":null,"name":null,"question":"<non-empty yes-or-no property question>"}}{"result":{"action":"GUESS","description":"<non-empty identifying description>","name":"<non-empty candidate name>","question":null}} A reply must match one of these formats exactly. Text fields in use must not be empty; unused fields must be JSON null.
Is this figure from Greek mythology?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Is this figure from Greek mythology?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
Achilles | ... Greek mythologyOpen britannica.com (opens in a new tab)
Is this figure a deity (a god or goddess)?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Is this figure a deity (a god or goddess)?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
Phoebus Apollo: “Wherefore, son of Peleus, dost thou pursue me with swift feet, thyself a mortal, while I am an immortal god?”Open theoi.com (opens in a new tab)
Is this figure a human or part-human character (such as a hero or demigod)?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Is this figure a human or part-human character (such as a hero or demigod)?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
Achilles was fathered by Peleus, a mortal father.Open britannica.com (opens in a new tab)
Is this figure male?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Is this figure male?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
sex or gender: maleOpen wikidata.org (opens in a new tab)
Did this figure participate in the Trojan War as told in Greek mythology?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Did this figure participate in the Trojan War as told in Greek mythology?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
Achilles ... was the greatest of all Greek heroes who took part in the Trojan War.Open greekmythology.com (opens in a new tab)
Did this figure fight on the Greek (Achaean) side in the Trojan War?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Did this figure fight on the Greek (Achaean) side in the Trojan War?"}}Oracle evidence1 model-reported source
The Oracle reported these excerpts and URLs. They are not independently checked.
Zeus agreed to give the Trojans success in the absence of Achilles, the best warrior of the Achaeans.Open en.wikipedia.org (opens in a new tab)
Is this figure best known for his cunning intelligence rather than physical strength in battle?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Is this figure best known for his cunning intelligence rather than physical strength in battle?"}}Oracle evidence2 model-reported sources
The Oracle reported these excerpts and URLs. They are not independently checked.
Achilles was the bravest, handsomest, and greatest warrior of Agamemnon’s army in the Trojan War.Open britannica.com (opens in a new tab)
Achilles is portrayed as tall and striking, with strength and looks that were unmatched among the Greek warriors.Open en.wikipedia.org (opens in a new tab)
Was this figure the son of a goddess?
Recorded Guesser outputRequired JSON format
{"result":{"action":"ASK","description":null,"name":null,"question":"Was this figure the son of a goddess?"}}Oracle evidence2 model-reported sources
The Oracle reported these excerpts and URLs. They are not independently checked.
Achilles, in Greek mythology, son of the mortal Peleus and the Nereid, or sea nymph, Thetis.Open britannica.com (opens in a new tab)
His mother was the goddess Thetis, a Nereid (sea nymph).Open kids.britannica.com (opens in a new tab)
Achilles
The greatest Greek warrior of the Trojan War, son of the nymph Thetis, nearly invulnerable except for his heel
Validator rationale The proposed identity matches Achilles, the Greek mythological hero and greatest Greek warrior of the Trojan War.
Recorded Guesser outputRequired JSON format
{"result":{"action":"GUESS","description":"The greatest Greek warrior of the Trojan War, son of the nymph Thetis, nearly invulnerable except for his heel","name":"Achilles","question":null}}