# User guide

The user guide explains the choices that sit between the quickstart and a defensible applied
analysis. Read it by task. Use the [Python API](../api/index.md) for signatures and the
[technical reference](../technical-reference/index.md) for derivations and evidence.

The public workflow has four visible stages:

```text
CausalStudy -> identify(typed estimand) -> IdentifiedEffect -> estimate(method) -> CausalResult
```

The study design owns the column roles. The estimand owns the causal question. The method owns
learning, targeting, inference, and runtime settings. That separation is what lets `cleverly`
refuse an unsupported combination before it fits any nuisance model.

The examples here are explanatory. The behavioural guarantees live in the fast tests and
registered validation studies, not in an example.

```{toctree}
:maxdepth: 2

data-design
estimands
methods-learners
results-assessment
longitudinal
capabilities
```