# Analysis result

The candidate return at window W3 is a note-for-note restatement of the opening theme (W1) in the home tonic D major, arriving after a six-measure dominant preparation in W2. All six cues score high, and the continuation window behaves like a recapitulation (tonic prolongation with a subdominant inflection) rather than continued development. This is a clear tonic double return.

Key observations: W3 measures 0–5 (E016–E021) match W1 measures 0–5 (E002–E007) exactly, including the octave-doubled D-major arpeggio theme, the repeated-A measure with C♯ trill, and even the chromatic D♯ in the sixth measure; the only detected difference is a missing staccato on one note. W2 sustains a dominant pedal — A5 held in the top voice for four full measures (E010–E013) with A recurring in the bass of every measure and a chromatically rising inner voice (B♭→B♮, C→C♯, D→D♯, E→F♯) — followed by a forte descending run that funnels directly onto the returning tonic (E014–E015). The return falls at roughly 39% of the second part (120.5 of 306.5 quarter notes), compatible with a recapitulatory division, if slightly early.

## Run metadata

- Analyst model: claude-fable-5 (Anthropic), running in a Claude agent harness.
- Sampling settings: not observable from within the session (unknown).
- Tools and external data: file, shell, and web tools were available in the harness but none were used; the analysis relied solely on the embedded dossier text.

## Machine-readable result

```json
{
  "schema_version": "2.1.0",
  "analyst_model": "claude-fable-5",
  "case_id": "CASE-D09B",
  "cues": {
    "tonal_stability": {
      "score": 4,
      "evidence_ids": ["E016", "E017", "E018", "E019"],
      "reason": "Observed: candidate opens with root-position D octaves and D-major arpeggio (D-A-D-F#) under 2-sharp signature, bass on D. Inference: home tonic D is structurally restored and prolonged at the candidate."
    },
    "thematic_correspondence": {
      "score": 4,
      "evidence_ids": ["E016", "E017", "E018", "E019", "E020", "E021", "E002", "E003", "E004", "E005", "E006", "E007"],
      "reason": "Observed: W3 measures 0-5 duplicate W1 measures 0-5 pitch-for-pitch and rhythm-for-rhythm, including trills; only a staccato differs (EV0026 vs EV0189). Inference: full, extended opening-theme return, not a fragment."
    },
    "preparation_strength": {
      "score": 4,
      "evidence_ids": ["E010", "E011", "E012", "E013", "E014", "E015"],
      "reason": "Observed: sustained A5 pedal four measures, bass A every measure, chromatic inner ascent, then forte descending run ending on E over A bass. Inference: prolonged dominant of D with intensifying retransition directly into the return."
    },
    "proportional_location": {
      "score": 3,
      "evidence_ids": ["E016"],
      "reason": "Observed: dossier places the candidate at 120.5 of 306.5 quarter notes of the second part (about 39%). Inference: compatible with a recapitulatory division, though somewhat early, leaving ample post-return space."
    },
    "rhetorical_emphasis": {
      "score": 3,
      "evidence_ids": ["E015", "E016", "E001"],
      "reason": "Observed: forte marked at the bass pickup preceding the return (DR0003); return restores two-octave doubling and the opening's low register, matching the opening's forte (DR0001). Inference: marked arrival, though no new dynamic at the downbeat itself."
    },
    "rotational_continuation": {
      "score": 4,
      "evidence_ids": ["E022", "E023", "E024", "E025", "E026", "E027", "E008", "E009"],
      "reason": "Observed: W4 measures 0-1 continue matching W1 measures 6-7, then tonic arpeggiation to D6, D pedal, C-natural inflection toward G. Inference: behaves as recapitulation with subdominant turn, not sequence or continued development."
    }
  },
  "status_distribution": {
    "not_recapitulation": 0.01,
    "off_tonic_recapitulation": 0.01,
    "tonic_double_return": 0.98
  },
  "suspected_recognition": {"level": "style", "confidence": 0.3},
  "case_note": "Exact tonic restatement of the opening theme after a six-measure dominant pedal with chromatic intensification and retransition run; continuation tracks the opening rotation then prolongs tonic with subdominant inflection. Strong tonic double return."
}
```

## Limitations

Missing dossier evidence: no tempo, no full-movement context beyond the four windows, no evidence for what precedes W2 or follows W4, and no explicit half-cadence or fermata marking at the retransition; the anacrusis measure E001 is only partially notated. Analytical uncertainty: the ~39% proportional position is somewhat early for a recapitulation, and the gap between W2 and W3 (if any) is not stated, so preparation continuity is inferred from voice-leading. The galant keyboard idiom feels stylistically familiar, but no work- or composer-level identification was used or attempted; scores rest solely on dossier content.
