Reason Codes¶

Every SandboxResult includes a reason field from the Reason enum explaining why the result was accepted or refused.

Accepted¶

Code	Value	Meaning
`ACCEPTED`	`"accepted"`	All quality gates passed. Dimension estimate is available.

Code	Value	Meaning
`EMPTY_GRAPH`	`"empty_graph"`	Input graph has no nodes.
`TRIVIAL_GRAPH`	`"trivial_graph"`	Graph has diameter ≤ 1 (complete graph, single edge, etc.).
`GIANT_COMPONENT_TOO_SMALL`	`"giant_component_too_small"`	Giant component is trivially small (0 or 1 nodes after extraction). Check `reason_detail` for `giant=N, total=M`.
`NO_VALID_RADII`	`"no_valid_radii"`	Too few distinct radii with non-trivial mass growth.
`NO_WINDOW_PASSES_R2`	`"no_window_passes_r2"`	No contiguous radius window achieves the minimum \( R^2 \) threshold. The graph likely has no power-law scaling regime.
`AICC_PREFERS_EXPONENTIAL`	`"aicc_prefers_exponential"`	Best window's AICc prefers exponential over power-law by the required margin. Suggests small-world rather than fractal structure.
`CURVATURE_GUARD`	`"curvature_guard"`	Best window has significant curvature in log-log space (quadratic fits better than linear).
`SLOPE_STABILITY_GUARD`	`"slope_stability_guard"`	Local slope varies too much across sub-windows. Scaling is not stable.
`NEGATIVE_SLOPE`	`"negative_slope"`	Best-fit slope is negative (mass decreases with radius). Only applies when `require_positive_slope=True`.

The post-hoc sandbox_quality_gate() function returns a QualityGateReason:

Code	Value	Meaning
`PASSED`	`"passed"`	Result meets all quality thresholds.
`NOT_ACCEPTED`	`"not_accepted"`	The underlying result was refused (dimension is None).
`R2_TOO_LOW`	`"r2_too_low"`	\( R^2 \) below gate threshold.
`STDERR_TOO_HIGH`	`"stderr_too_high"`	Slope standard error too high.
`LOG_SPAN_TOO_SMALL`	`"log_span_too_small"`	Scaling window too narrow in log space.
`RADIUS_RATIO_TOO_SMALL`	`"radius_ratio_too_small"`	r_max/r_min ratio too small.
`AICC_MARGIN_TOO_SMALL`	`"aicc_margin_too_small"`	AICc margin below gate threshold.