{
  "vercy": "1.0-draft",
  "publication": {
    "status": "research-draft",
    "adjudicationStatus": "unreviewed",
    "publishableCanonical": false,
    "generatedAt": "2026-09-07T15:13:56Z",
    "providers": [
      "Codex",
      "Grok"
    ],
    "missingProviders": [],
    "pass": 2,
    "cost": {
      "grok": {
        "usd": 0.00514862,
        "turns": 1,
        "seconds": 58.3,
        "error": null
      },
      "codex": {
        "seconds": 79.2,
        "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.3\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a07c6c-04bf-7a01-8f45-395437c9920f\n--------\nuser\nYou are drafting a Vercy meta-model for one registered thing. Answer as JSON only, no prose around it.\n\nThing: tongue-twister\nRegistry id: vr.tr.tongue-twister\nPlane / domain: INF / INF.MED\nRegistry definition: (none recorded)\nNames folded into this entry: (no"
      }
    },
    "enrichment": {
      "pass": 3,
      "engine": "claude",
      "producedAt": "2026-10-06T12:00:00Z",
      "ingestedAt": "2026-10-06T08:39:32+00:00",
      "fields": [
        "agent_conduct",
        "ethics",
        "owners"
      ]
    },
    "gate": {
      "passed": true,
      "version": "1.0",
      "at": "2026-10-07T10:10:28+00:00",
      "evidence": [
        "completeness 1.00",
        "sense: Wikidata description",
        "4 live sources",
        "review by codex: pass"
      ]
    }
  },
  "metaModel": {
    "id": "THING-Q230052",
    "registryId": "vr.tr.tongue-twister",
    "name": "tongue-twister",
    "version": "0.1.0-research.1",
    "entryKind": "thing",
    "family": "Thing Registry",
    "domain": [
      "INF.MED"
    ],
    "status": "research-draft"
  },
  "canonicalUrl": "https://ver.cy/models/thing/q230052/",
  "model": {
    "registry_id": "vr.tr.tongue-twister",
    "name": "tongue-twister",
    "purpose": "Enable an AI agent to recognise a tongue-twister, assess its pronunciation challenge for a stated speaker and context, and decide how it may be presented, practised, adapted or evaluated.",
    "definition": "A short spoken formula whose phoneme sequence is deliberately hard to articulate at speed, typically by packing similar or rapidly alternating sounds so that motor planning and coarticulation collide.",
    "scope_statement": "This model owns the tongue-twister as a reproducible verbal expression organised or used to challenge accurate articulation, including its wording, sound patterns, pronunciation variants, delivery conditions and evidence of difficulty.",
    "in_scope": [
      "Canonical or locally selected wording, sequence boundaries and repeat instructions",
      "Language, dialect and pronunciation variants that affect the challenge",
      "Sound sequences proposed or observed to provoke articulation errors",
      "Speaker-relative difficulty under specified delivery conditions",
      "Tongue-twister-specific practice, adaptation and assessment",
      "Attribution and relationships among wording or pronunciation variants"
    ],
    "out_of_scope": [
      "Clinical diagnosis or treatment plans for speech and language conditions",
      "A speaker's general proficiency, identity or complete learning history",
      "General phonological descriptions of a language or dialect",
      "Audio-file storage, recording equipment and media asset management",
      "Complete models of poems, jokes, songs or games containing a tongue-twister",
      "General copyright administration and publication workflows"
    ],
    "distinguishing_features": [
      "An articulation challenge can be identified or investigated in the expression's sound sequence; repetition or alliteration alone is insufficient.",
      "Successful performance concerns producing the intended sequence accurately under stated conditions, rather than solving a riddle or interpreting a difficult meaning.",
      "The challenge can be specified for a pronunciation variety; difficult spelling alone does not establish that an expression is a tongue-twister.",
      "A difficult isolated word is not automatically a tongue-twister: record evidence that it is constructed, repeated or used as an articulation challenge.",
      "A joke, poem or vocal exercise may also be a tongue-twister when its articulatory challenge can be identified independently of its other function."
    ],
    "characteristics": [
      {
        "name": "Expression boundary",
        "kind": "category",
        "unit_or_values": "word, phrase, sentence, multi-sentence passage, repeated sequence",
        "why_it_matters": "Determines the unit that must be reproduced and whether repetition forms part of the challenge."
      },
      {
        "name": "Pronunciation variety",
        "kind": "relation",
        "unit_or_values": "Links to the language, dialect or explicitly supplied pronunciation used for assessment",
        "why_it_matters": "The same wording may present different sound contrasts and challenges across varieties."
      },
      {
        "name": "Challenge-bearing sound sequence",
        "kind": "category",
        "unit_or_values": "Recorded phonetic sequence with candidate features such as sound alternation, similar syllables, consonant clusters or shifting word boundaries",
        "why_it_matters": "Locates the proposed articulation challenge instead of treating the entire text as uniformly difficult."
      },
      {
        "name": "Sequence length",
        "kind": "measurement",
        "unit_or_values": "Words and syllables per complete rendition, with counting convention",
        "why_it_matters": "Supports comparison of delivery rates and distinguishes a short repeated challenge from a long passage."
      },
      {
        "name": "Delivery rate",
        "kind": "measurement",
        "unit_or_values": "Syllables per second under a specified timing convention",
        "why_it_matters": "Difficulty and apparent improvement cannot be interpreted without delivery speed."
      },
      {
        "name": "Repetition requirement",
        "kind": "measurement",
        "unit_or_values": "Consecutive renditions required, with permitted pauses",
        "why_it_matters": "Errors may arise across repetitions even when one rendition is accurate."
      },
      {
        "name": "Observed error pattern",
        "kind": "category",
        "unit_or_values": "Substitution, omission, insertion, transposition, restart or other explicitly described event",
        "why_it_matters": "Shows where performance departs from the target and guides targeted practice."
      },
      {
        "name": "Accurate completion proportion",
        "kind": "measurement",
        "unit_or_values": "Accurate attempts divided by scored attempts for a stated speaker or group and protocol",
        "why_it_matters": "Provides contextual evidence of difficulty without assigning a universal difficulty score."
      },
      {
        "name": "Challenge evidence state",
        "kind": "state",
        "unit_or_values": "Proposed from wording, reported by a source, observed in attempts, mixed evidence",
        "why_it_matters": "Separates a plausible sound-pattern analysis from demonstrated performance difficulty."
      },
      {
        "name": "Variant relationship",
        "kind": "relation",
        "unit_or_values": "Wording variant, pronunciation variant, extension, shortening, translation or sound-pattern adaptation",
        "why_it_matters": "Prevents unlike challenges from being pooled under one text label."
      }
    ],
    "affordances": [
      "Present the exact wording with pronunciation guidance and explicit repetition conditions.",
      "Locate challenge-bearing sound transitions and generate focused practice segments.",
      "Compare attempts under matched pronunciation, rate and scoring conditions.",
      "Adjust pace, segmentation or repetition count while recording how the challenge changes.",
      "Propose wording or language adaptations and flag the need to reassess their articulation challenge.",
      "Explain whether tongue-twister classification is supported, provisional or dependent on a particular pronunciation."
    ],
    "agent_conduct": {
      "may": [
        "Teach and use tongue-twisters for language practice, speech exercises and play.",
        "Translate or adapt them, noting that sound play rarely survives translation."
      ],
      "must_not": [
        "Mock a person's stutter or speech difficulty with tongue-twisters.",
        "Use them to humiliate learners or people with accents."
      ],
      "requires_human": [
        "Using them in speech therapy for a person with a speech disorder."
      ]
    },
    "ethics": {
      "considerations": [
        "Speech play is fun, but failure can embarrass people who struggle to speak."
      ],
      "affected_parties": [
        "People who stutter",
        "Language learners",
        "Children"
      ]
    },
    "owners": {
      "steward": "Nobody owns traditional tongue-twisters; authors hold rights in new ones.",
      "master_systems": []
    },
    "what_it_is_for": [
      "Tongue-twisters are used in wordplay, language learning and speech or performance warm-ups.",
      "They provide short pronunciation challenges through repeated or alternating sounds that are difficult to articulate fluently.",
      "Their difficulty depends on the speaker's language background, familiarity and speaking rate."
    ],
    "visual_identification": [
      "The written or spoken phrase contains a conspicuous concentration of similar or alternating speech sounds.",
      "Repeated attempts commonly produce sound substitutions or ordering errors, especially as speaking speed increases.",
      "The wording often emphasizes sound patterns over conveying practical information."
    ],
    "failure_modes_and_hazards": [
      "Public pressure to perform accurately can cause embarrassment or exclusion for speakers with speech differences or limited language familiarity.",
      "Treating tongue-twister performance as a diagnostic measure can lead to unsupported judgments about speech ability or cognitive function."
    ],
    "facets_not_applicable": {
      "interfaces": "No specific standard, law or official classification applies to tongue-twisters as a general linguistic form."
    }
  },
  "sources": [
    {
      "id": "know-en-wikipedia-tongue-twister",
      "title": "Tongue-twister",
      "url": "https://en.wikipedia.org/wiki/Tongue-twister",
      "what_it_supports": "Common-language definition, named examples, and cross-linguistic labels (trabalenguas, Zungenbrecher, virelangue, hayakuchi kotoba).",
      "url_status": "live"
    },
    {
      "id": "know-wikidata-q163244",
      "title": "tongue twister (Q163244)",
      "url": "https://www.wikidata.org/wiki/Q163244",
      "what_it_supports": "Stable identifier for the concept as a literary/speech form.",
      "url_status": "live"
    },
    {
      "id": "know-crystal-cambridge-encyclopedia-language",
      "title": "The Cambridge Encyclopedia of Language",
      "url": "",
      "what_it_supports": "Places tongue-twisters among word-play and speech-error phenomena rather than as a literary genre with a governing standard."
    },
    {
      "id": "wikidata",
      "title": "Wikidata item Q230052: tongue-twister",
      "url": "https://www.wikidata.org/wiki/Q230052",
      "url_status": "live",
      "what_it_supports": "identity and sense of the item",
      "checked_by": "wikidata-api"
    },
    {
      "id": "wikipedia-en",
      "title": "Wikipedia: Tongue twister",
      "url": "https://en.wikipedia.org/wiki/Tongue_twister",
      "url_status": "live",
      "what_it_supports": "general description of the item",
      "checked_by": "wikidata-api sitelink"
    }
  ],
  "structure": {
    "bundles": [
      {
        "id": "verbal-form-and-boundaries",
        "name": "Verbal form and boundaries",
        "description": "Establishes exactly what must be spoken and where a rendition begins and ends.",
        "rationale": "Small wording changes and repetition boundaries can change the articulation challenge.",
        "layers": [
          {
            "id": "target-expression",
            "name": "Target expression",
            "description": "Captures the selected verbal sequence without silently combining variants.",
            "findings": [
              {
                "id": "reproducible-wording",
                "name": "Reproducible wording",
                "description": "Record the wording, order and any uncertainty in transcription or oral transmission.",
                "questions": [
                  {
                    "text": "What exact sequence constitutes the selected tongue-twister?",
                    "kind": "definition",
                    "id": "reproducible-wording-q01"
                  },
                  {
                    "text": "Which words or ordering differ across the available versions, and which version is being assessed?",
                    "kind": "boundary",
                    "id": "reproducible-wording-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "rendition-and-repetition",
            "name": "Rendition and repetition",
            "description": "Distinguishes the base expression from the instructions that turn it into a performance task.",
            "findings": [
              {
                "id": "challenge-unit",
                "name": "Challenge unit",
                "description": "Record the rendition boundary, repeat count and treatment of transitions between repeats.",
                "questions": [
                  {
                    "text": "Does the challenge require one rendition or a specified number of consecutive repeats?",
                    "kind": "definition",
                    "id": "challenge-unit-q01"
                  },
                  {
                    "text": "Are pauses allowed between repeats, and is the transition from the final sound back to the first part of the challenge?",
                    "kind": "boundary",
                    "id": "challenge-unit-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "pronunciation-and-articulation",
        "name": "Pronunciation and articulation",
        "description": "Connects the written or remembered expression to the sounds and transitions being challenged.",
        "rationale": "A tongue-twister's challenge must be assessed through pronunciation rather than inferred from spelling alone.",
        "layers": [
          {
            "id": "pronunciation-target",
            "name": "Pronunciation target",
            "description": "Makes the relevant language variety and accepted realisations explicit.",
            "findings": [
              {
                "id": "variety-dependent-target",
                "name": "Variety-dependent target",
                "description": "Record the pronunciation used and distinguish accepted variation from performance errors.",
                "questions": [
                  {
                    "text": "Which language variety and pronunciation establish the target sound sequence?",
                    "kind": "definition",
                    "id": "variety-dependent-target-q01"
                  },
                  {
                    "text": "Which alternate pronunciations are acceptable, and do they retain the proposed challenge?",
                    "kind": "boundary",
                    "id": "variety-dependent-target-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "challenge-bearing-transitions",
            "name": "Challenge-bearing transitions",
            "description": "Identifies candidate points of articulatory competition and the evidence supporting them.",
            "findings": [
              {
                "id": "sound-pattern-hypothesis",
                "name": "Sound-pattern hypothesis",
                "description": "Record specific sound sequences proposed to drive difficulty and distinguish hypotheses from observed errors.",
                "questions": [
                  {
                    "text": "Which exact sound transitions or recurring syllable patterns are proposed to make accurate delivery difficult?",
                    "kind": "definition",
                    "id": "sound-pattern-hypothesis-q01"
                  },
                  {
                    "text": "Do recorded attempts show errors at those locations, or is the explanation currently based only on analysis of the sequence?",
                    "kind": "measurement",
                    "id": "sound-pattern-hypothesis-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "performance-and-difficulty",
        "name": "Performance and difficulty",
        "description": "Records how the expression performs as a challenge under explicit speaking and scoring conditions.",
        "rationale": "Difficulty depends on who speaks, how the task is delivered and what counts as success.",
        "layers": [
          {
            "id": "attempt-conditions",
            "name": "Attempt conditions",
            "description": "Captures conditions needed to interpret or compare a rendition.",
            "findings": [
              {
                "id": "comparable-delivery",
                "name": "Comparable delivery",
                "description": "Record pace, repetition, reading or recall, and relevant familiarity without treating them as properties of every speaker.",
                "questions": [
                  {
                    "text": "At what rate and repeat count was the expression attempted, and was it read, recalled or imitated?",
                    "kind": "measurement",
                    "id": "comparable-delivery-q01"
                  },
                  {
                    "text": "What prior practice and familiarity with the language or expression are known for this attempt?",
                    "kind": "provenance",
                    "id": "comparable-delivery-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "accuracy-and-breakdown",
            "name": "Accuracy and breakdown",
            "description": "Records success criteria and the location and type of deviations from the target.",
            "findings": [
              {
                "id": "scored-articulation",
                "name": "Scored articulation",
                "description": "Assess errors and completion against a declared target while preserving scoring uncertainty.",
                "questions": [
                  {
                    "text": "What counts as a failed attempt, including pauses, self-corrections and restarts?",
                    "kind": "definition",
                    "id": "scored-articulation-q01"
                  },
                  {
                    "text": "Which errors occurred at which sequence positions, and how many attempts met the success criterion?",
                    "kind": "measurement",
                    "id": "scored-articulation-q02"
                  },
                  {
                    "text": "Which sounds or events could not be scored confidently from the available evidence?",
                    "kind": "boundary",
                    "id": "scored-articulation-q03"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "practice-and-adaptation",
        "name": "Practice and adaptation",
        "description": "Governs changes to presentation or wording for a stated tongue-twister activity.",
        "rationale": "An agent must distinguish adjustments to practice conditions from changes that create a different articulation task.",
        "layers": [
          {
            "id": "practice-progression",
            "name": "Practice progression",
            "description": "Supports deliberate manipulation of pace, chunking and repeat count.",
            "findings": [
              {
                "id": "targeted-practice-step",
                "name": "Targeted practice step",
                "description": "Select a practice adjustment tied to an observed or proposed difficulty and a stated objective.",
                "questions": [
                  {
                    "text": "Is the immediate objective accurate sound order, fluent repetition, faster delivery or playful performance?",
                    "kind": "action",
                    "id": "targeted-practice-step-q01"
                  },
                  {
                    "text": "Which segment, pace or repeat count should change next, and what observed result would justify progressing?",
                    "kind": "action",
                    "id": "targeted-practice-step-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "challenge-preserving-editing",
            "name": "Challenge-preserving editing",
            "description": "Evaluates whether adaptations retain the intended sound pattern.",
            "findings": [
              {
                "id": "adaptation-consequences",
                "name": "Adaptation consequences",
                "description": "Record how substitutions, translations or shorter versions alter the target articulation task.",
                "questions": [
                  {
                    "text": "Which sound sequence must an adaptation retain to serve the intended practice or performance objective?",
                    "kind": "boundary",
                    "id": "adaptation-consequences-q01"
                  },
                  {
                    "text": "After editing or translation, what pronunciation analysis and trial attempts are needed before claiming comparable difficulty?",
                    "kind": "action",
                    "id": "adaptation-consequences-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "attestation-and-classification",
        "name": "Attestation and classification",
        "description": "Establishes where the expression and its tongue-twister designation come from.",
        "rationale": "A familiar label, uncertain attribution or shared opening phrase does not establish a unique version or verified challenge.",
        "layers": [
          {
            "id": "wording-and-attribution-evidence",
            "name": "Wording and attribution evidence",
            "description": "Connects the selected version to identifiable written, recorded or reported attestations.",
            "findings": [
              {
                "id": "attested-version",
                "name": "Attested version",
                "description": "Record evidence for wording and attribution separately from claims about original authorship.",
                "questions": [
                  {
                    "text": "Which identifiable source or recorded contribution supplies this exact wording?",
                    "kind": "provenance",
                    "id": "attested-version-q01"
                  },
                  {
                    "text": "Does the available evidence establish authorship, merely document use, or leave attribution unresolved?",
                    "kind": "provenance",
                    "id": "attested-version-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "tongue-twister-status",
            "name": "Tongue-twister status",
            "description": "Tests classification while allowing overlap with other verbal forms.",
            "findings": [
              {
                "id": "articulation-challenge-basis",
                "name": "Articulation challenge basis",
                "description": "Record why the expression qualifies as a tongue-twister and any limits to that assessment.",
                "questions": [
                  {
                    "text": "What evidence supports treating this expression as an articulation challenge rather than relying solely on repetition, alliteration or unfamiliar vocabulary?",
                    "kind": "boundary",
                    "id": "articulation-challenge-basis-q01"
                  },
                  {
                    "text": "Is the designation supported by documented use, observed performance difficulty, explicit construction intent or only an untested proposal?",
                    "kind": "provenance",
                    "id": "articulation-challenge-basis-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "evidence-and-external-alignment",
        "name": "Evidence and external alignment",
        "description": "What the world already says about this thing, gathered so the model can be checked against it.",
        "rationale": "A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.",
        "layers": [
          {
            "id": "reported-evidence",
            "name": "Reported evidence",
            "description": "Findings from the breadth pass, kept separate from the structural claims.",
            "findings": [
              {
                "id": "evidence-kinds",
                "name": "Kinds and varieties",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  "alliterative phrase (same initial consonant repeated)",
                  "alternating-onset pair (rapid switch between similar consonants, e.g. s/sh, p/b)",
                  "sibilant/fricative cluster twister",
                  "liquid/rhotic twister (l/r, r-clusters)",
                  "vowel-contrast twister (near-identical vowels in tight succession)",
                  "proper-name / nursery-rhyme twister (Peter Piper, She sells seashells)",
                  "shibboleth used as a twister (diagnostic of accent or L2 phonology)",
                  "performance/acting warm-up (stage diction drills)"
                ],
                "questions": [
                  {
                    "id": "evidence-kinds-q01",
                    "text": "Which of these kinds and varieties hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-identifiers",
                "name": "Identifiers and schemes",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  {
                    "scheme": "Wikidata",
                    "value_or_pattern": "Q163244",
                    "note": "item 'tongue twister'"
                  },
                  {
                    "scheme": "Library of Congress Subject Headings",
                    "value_or_pattern": "Tongue twisters",
                    "note": "LCSH topical heading used in catalogue records"
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-identifiers-q01",
                    "text": "Which of these identifiers and schemes hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-real-world-use",
                "name": "Real-world use",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  "Children's oral games and party recitation, often as a speed contest.",
                  "Speech-language pathology and accent/diction training: drills that stress a target contrast (s/ʃ, r/l, consonant clusters).",
                  "Actor and broadcaster warm-ups for articulatory agility.",
                  "Psycholinguistic experiments on slips of the tongue and speech-motor planning.",
                  "Second-language classrooms as pronunciation practice and ice-breakers.",
                  "Advertising slogans and radio jingles that trade on memorable phonetic difficulty."
                ],
                "questions": [
                  {
                    "id": "evidence-real-world-use-q01",
                    "text": "Which of these real-world use hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-measurements",
                "name": "Typical measurements",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  {
                    "quantity": "speaking rate at which errors appear",
                    "typical_range": "often elicited above conversational rate; experimental tasks commonly 3-6 syllables/s",
                    "unit": "syllables per second"
                  },
                  {
                    "quantity": "error rate (substitutions, transpositions, omissions)",
                    "typical_range": "near zero at slow rate; rises sharply under speed or dual-task load",
                    "unit": "errors per attempt or per 100 syllables"
                  },
                  {
                    "quantity": "length of the formula",
                    "typical_range": "typically 3-20 words; canonical English examples are one sentence",
                    "unit": "words"
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-measurements-q01",
                    "text": "Which of these typical measurements hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-failure-modes-and-hazards",
                "name": "Failure modes and hazards",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  "Articulatory breakdown: sound substitutions, metathesis, and blends (the intended comic or diagnostic effect).",
                  "Fossilizing an incorrect target if used as a therapy drill without a correct model.",
                  "Choking or aspiration risk is not characteristic; the hazard is communicative (unintelligibility, embarrassment) rather than physical.",
                  "In experimental or clinical use, fatigue and frustration if rate is pushed without rest."
                ],
                "questions": [
                  {
                    "id": "evidence-failure-modes-and-hazards-q01",
                    "text": "Which of these failure modes and hazards hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-regional-variation",
                "name": "Regional variation",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  "English 'tongue-twister'; German Zungenbrecher; French virelangue; Spanish/Portuguese trabalenguas; Italian scioglilingua; Japanese hayakuchi kotoba; Chinese 绕口令 (ràokǒulìng).",
                  "Canonical examples are language-specific because they exploit that language's phoneme inventory (English s/ʃ seashells; Japanese ra/la is not a native contrast; Mandarin tone-plus-segment sequences).",
                  "Some cultures treat them primarily as children's folklore; others (e.g. stage schools in the UK) as professional diction exercises."
                ],
                "questions": [
                  {
                    "id": "evidence-regional-variation-q01",
                    "text": "Which of these regional variation hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-neighbours",
                "name": "Neighbouring kinds and how to tell them apart",
                "description": "Reported by the breadth pass; each item needs checking against its source before it becomes normative.",
                "evidence": [
                  {
                    "name": "alliteration / alliterative verse",
                    "difference": "Alliteration is a sound-patterning device that need not be hard to say; a tongue-twister uses crowding of similar sounds specifically to impede fluent articulation."
                  },
                  {
                    "name": "spoonerism",
                    "difference": "A spoonerism is an already-occurred transposition of onsets; a tongue-twister is a stimulus designed to provoke such errors."
                  },
                  {
                    "name": "shibboleth",
                    "difference": "A shibboleth distinguishes in-group pronunciation or identity; it becomes a tongue-twister only when the difficulty is articulatory speed rather than social marking."
                  },
                  {
                    "name": "lipogram / constrained writing",
                    "difference": "Those are orthographic or lexical constraints on writing; a tongue-twister is defined by spoken motor difficulty."
                  },
                  {
                    "name": "minimal pair drill",
                    "difference": "A minimal-pair drill isolates one contrast for perception/production; a tongue-twister typically stacks many similar gestures in sequence."
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-neighbours-q01",
                    "text": "Which of these neighbouring kinds and how to tell them apart hold for the sense of tongue-twister this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "openQuestions": [
    "What minimum evidence should establish tongue-twister status for a newly generated expression with no documented use?",
    "When should wording or pronunciation variants count as versions of one tongue-twister rather than distinct challenges?",
    "Which timing and error-scoring conventions yield useful comparisons across languages and pronunciation varieties?",
    "How reliably can difficulty caused by articulation be separated from difficulty caused by unfamiliar vocabulary, reading or memory demands?",
    "What evidence would justify claims that practice with a particular tongue-twister improves speech beyond performance on that expression?"
  ],
  "statistics": {
    "bundles": 6,
    "layers": 11,
    "findings": 17,
    "questions": 28
  }
}
