diff --git a/docs/dev/adrs/suggestions/documentation-ci-build.md b/docs/dev/adrs/accepted/documentation-ci-build.md
similarity index 67%
rename from docs/dev/adrs/suggestions/documentation-ci-build.md
rename to docs/dev/adrs/accepted/documentation-ci-build.md
index f3a858832..e7e0e8885 100644
--- a/docs/dev/adrs/suggestions/documentation-ci-build.md
+++ b/docs/dev/adrs/accepted/documentation-ci-build.md
@@ -1,6 +1,6 @@
 # ADR: Documentation CI and Build Verification
 
-**Status:** Proposed  
+**Status:** Accepted  
 **Date:** 2026-05-31
 
 ## Group
@@ -77,6 +77,20 @@ Use `codespell` first for low-noise spelling checks. Consider `Vale`
 after the project has a small EasyDiffraction style vocabulary and an
 allowlist for crystallographic terms, package names, and CIF tags.
 
+## Implementation Status
+
+Most of this ADR is already in place; it is accepted to record the
+chosen direction and to track the remaining gaps.
+
+| #   | Decision                     | Status                                                                                                                                                                                       |
+| --- | ---------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| 1   | MkDocs `--strict` build      | **Done** — `docs-build` pixi task runs `mkdocs build --strict`; wired into the `lint-format.yml` "docs strict build" gate and the `docs.yml` deploy workflow.                                |
+| 2   | `mkdocstrings` for API pages | **Done** — `mkdocstrings` + `mkdocstrings-python` configured in `docs/mkdocs.yml` (handler `paths: ['src']`); the `api-reference/*.md` pages use `:::` directives.                           |
+| 3   | Snippet smoke tests          | **Not done** — no task imports or executes the user-facing snippets in `quick-reference/`, `user-guide/first-steps.md`, or `user-guide/analysis-workflow/*.md`. Highest-value remaining gap. |
+| 4   | Tutorial freshness check     | **Partial** — `notebook-prepare` plus `notebook-tests`/`notebook-exec-ci` exist, but no no-write task asserts that `notebook-prepare` leaves the committed `.ipynb` unchanged.               |
+| 5   | `lychee` link checking       | **Done for local/relative links** — `link-check` pixi task (config in `lychee.toml`) is wired into `lint-format.yml`. External-URL checking is deferred (see issue 114).                     |
+| 6   | `codespell`, then `Vale`     | **codespell done** — `spell-check` pixi task wired into `lint-format.yml`. `Vale` deferred.                                                                                                  |
+
 ## Options Considered
 
 ### MkDocs strict build
@@ -179,11 +193,14 @@ Cons:
 
 ## Deferred Work
 
-- Decide whether link checking runs on every pull request, nightly, or
-  both.
-- Decide whether snippet smoke tests extract fenced code blocks
+- Add snippet smoke tests for user-facing examples (decision 3). Tracked
+  by the `documentation-snippet-tests` implementation plan. Open
+  question carried into that plan: extract fenced code blocks
   automatically or rely on explicitly named snippets.
-- Decide whether docs CI should build only source Markdown or also build
-  rendered notebooks.
-- Add the chosen checks to `pixi.toml`, CI configuration, and developer
-  documentation after this ADR is accepted.
+- Add a no-write `notebook-prepare-check` task that fails CI when the
+  committed notebooks are out of date with their `.py` sources (decision
+  4).
+- Enable external-URL link checking in the docs gate (decision 5),
+  scheduled or cached to avoid flakiness. Tracked by issue 114.
+- Adopt `Vale` prose linting once an EasyDiffraction style vocabulary
+  and crystallographic-term allowlist exist (decision 6).
diff --git a/docs/dev/adrs/accepted/plotting-docs-performance.md b/docs/dev/adrs/accepted/plotting-docs-performance.md
index 3d68101a4..d6a9109fd 100644
--- a/docs/dev/adrs/accepted/plotting-docs-performance.md
+++ b/docs/dev/adrs/accepted/plotting-docs-performance.md
@@ -450,7 +450,7 @@ Settled in discussion on 2026-06-02:
   payload + faster draw) — a separate, data-side optimization.
 - A docs CI budget check (page weight / figure count) to catch
   regressions, aligning with
-  [`documentation-ci-build.md`](../suggestions/documentation-ci-build.md).
+  [`documentation-ci-build.md`](documentation-ci-build.md).
 - Hoist a single importmap into the **report** template `<head>` for
   standalone reports that render multiple Three.js scenes (the same
   per-scene-importmap bug as docs, but governed by
diff --git a/docs/dev/adrs/accepted/test-suite-and-validation.md b/docs/dev/adrs/accepted/test-suite-and-validation.md
index b35aea302..6d0744057 100644
--- a/docs/dev/adrs/accepted/test-suite-and-validation.md
+++ b/docs/dev/adrs/accepted/test-suite-and-validation.md
@@ -66,7 +66,7 @@ accumulated:
   slow and therefore runs on pull requests only. There is no fast,
   every-push check that the site builds strictly, links resolve, and
   prose is clean. This overlaps the unimplemented
-  [Documentation CI and Build Verification](../suggestions/documentation-ci-build.md)
+  [Documentation CI and Build Verification](documentation-ci-build.md)
   suggestion.
 
 This ADR amends [Test Strategy](../accepted/test-strategy.md): the
@@ -338,7 +338,7 @@ prompt drift feedback. It is deliberately **separate from `docs.yml`**,
 which executes all tutorials and then builds and deploys — slow, and
 therefore pull-request-only. The detailed catalogue of documentation
 checks is owned by
-[Documentation CI and Build Verification](../suggestions/documentation-ci-build.md),
+[Documentation CI and Build Verification](documentation-ci-build.md),
 which this ADR coordinates with: that ADR defines _what_ the checks are;
 this ADR's decision is that the cheap, deterministic subset runs as part
 of the every-push test workflow. Promoting that ADR is part of this
@@ -443,15 +443,15 @@ drafting conversation, per the dependency-approval rule):
 - `pytest-benchmark` — performance-regression benchmarks (§7).
 
 Coordinated with
-[Documentation CI and Build Verification](../suggestions/documentation-ci-build.md),
+[Documentation CI and Build Verification](documentation-ci-build.md),
 which carries the documentation-check tools (`codespell`, a link checker
 such as `lychee`, and later `Vale`) used by §9.
 
 ## Related ADRs
 
 - [Test Strategy](../accepted/test-strategy.md) — amended by this ADR.
-- [Documentation CI and Build Verification](../suggestions/documentation-ci-build.md)
-  — coordinated with §9.
+- [Documentation CI and Build Verification](documentation-ci-build.md) —
+  coordinated with §9.
 - [Lint Complexity Thresholds](../accepted/lint-complexity-thresholds.md)
   — sibling Quality guardrail.
 - [Notebook Generation Source of Truth](../accepted/notebook-generation.md)
diff --git a/docs/dev/adrs/index.md b/docs/dev/adrs/index.md
index 17e2d85a1..b4e98e0d9 100644
--- a/docs/dev/adrs/index.md
+++ b/docs/dev/adrs/index.md
@@ -33,7 +33,7 @@ folders.
 | Documentation        | Accepted   | Help Method Discoverability                         | Requires primary public objects and facades to expose consistent `help()` output.                                          | [`help-discoverability.md`](accepted/help-discoverability.md)                               |
 | Documentation        | Accepted   | Notebook Generation Source of Truth                 | Treats tutorial `.py` files as editable sources and notebooks as generated artifacts.                                      | [`notebook-generation.md`](accepted/notebook-generation.md)                                 |
 | Documentation        | Accepted   | Plotting & Docs Performance for Interactive Figures | Self-hosts a lazy, shared figure runtime so docs pages load fast and progressively while staying interactive.              | [`plotting-docs-performance.md`](accepted/plotting-docs-performance.md)                     |
-| Documentation        | Suggestion | Documentation CI and Build Verification             | Proposes strict MkDocs builds, API-derived docs, snippet smoke tests, link checks, and prose/spelling checks.              | [`documentation-ci-build.md`](suggestions/documentation-ci-build.md)                        |
+| Documentation        | Accepted   | Documentation CI and Build Verification             | Strict MkDocs builds, API-derived docs, snippet smoke tests, link checks, and prose/spelling checks.                       | [`documentation-ci-build.md`](accepted/documentation-ci-build.md)                           |
 | Experiment model     | Accepted   | Immutable Experiment Type                           | Makes experiment type axes creation-time state rather than mutable runtime state.                                          | [`immutable-experiment-type.md`](accepted/immutable-experiment-type.md)                     |
 | Experiment model     | Accepted   | Automatic Line-Segment Background Estimation        | Detects line-segment background control points from the measured pattern, peak-insensitive and editable.                   | [`background-auto-estimate.md`](accepted/background-auto-estimate.md)                       |
 | Experiment model     | Accepted   | Calculation Without Measured Data                   | Adds a writable `data_range` category so a structure-only experiment is calculable and plottable without loaded data.      | [`calculation-without-measured-data.md`](accepted/calculation-without-measured-data.md)     |
diff --git a/docs/dev/adrs/suggestions/model-sample-absorption.md b/docs/dev/adrs/suggestions/model-sample-absorption.md
new file mode 100644
index 000000000..838e71986
--- /dev/null
+++ b/docs/dev/adrs/suggestions/model-sample-absorption.md
@@ -0,0 +1,377 @@
+# ADR: Model Sample Absorption (Debye–Scherrer, μR)
+
+## Status
+
+Proposed.
+
+## Date
+
+2026-06-12
+
+## Group
+
+Experiment model.
+
+## Context
+
+This ADR follows the conventions in
+[`AGENTS.md`](../../../../AGENTS.md).
+
+The calculators (`cryspy`, `crysfml`) currently apply **no**
+sample-absorption correction. For a cylindrical sample in Debye–Scherrer
+geometry the transmission through the sample is an angle-dependent
+factor that attenuates low-angle peaks more than high-angle peaks;
+omitting it leaves an angle-dependent intensity residual that scales
+with the sample's μR (linear absorption coefficient × radius).
+
+This is not hypothetical. The verification reference
+`pd-neut-cwl_tch-fcj_lab6` was refined in FullProf with **μR = 0.7**;
+the unmodelled correction is the _entire_ intensity residual on the
+companion `pd-neut-cwl_tch-fcj_abs_lab6` page (≈5 % profile difference),
+while the μR = 0 page passes to corr 0.9999. See
+[issue #119](../../issues/open.md).
+
+### What the three reference sources provide
+
+**FullProf** splits absorption into a refineable **magnitude** and a
+**correction type**, on two different axes:
+
+- **CW (and symmetric θ–2θ flat plate):** `muR` on the `.pcr` Lambda
+  line — a single value (μ·R). In the LaB₆ reference it is **fixed**
+  (the Lambda line carries no refinement codeword), confirming that
+  absorption is typically entered as a known constant, not refined. A
+  `2nd-muR` field on the same line models a second coaxial cylinder (the
+  sample container / capillary wall); `Cthm` and `Rpolarz` on that line
+  are **polarization**, not absorption, and are out of scope here.
+- **TOF:** `Iabscor` selects the correction _form_ — `1` flat plate ⟂
+  incident beam, `2` cylindrical, `3` exponential `A = exp(−ABS·λᶜ)`.
+  TOF absorption is wavelength-dependent, not a pure function of 2θ.
+
+**CrysFML08** (`Src/CFML_Powder/Pow_Lorentz_Absorption.f90`) already
+implements the CW formulas in Fortran:
+
+- `Lorentz_abs_CW(sinth, costh, postt, tmv, …, ilor, cabs, …)` with
+  `tmv = μR`, `ilor` = geometry (`DBS`, `BB`, `TBG`, `TFX`, `FILMS`…)
+  and `cabs ∈ {HEWAT, LOBANOV}`.
+- `Powder_Lorentz_IntegInt_CW(…, muR, …)` — the bare Hewat form.
+
+**However**, these routines are **not wrapped** in CrysFML's
+`PythonAPI/`, and the high-level entry our backend actually calls
+(`cw_powder_pattern_from_dict`) computes a plain Lorentz factor
+`0.5/(sin²θ·cosθ)` with no absorption term. So the issue's claim that
+absorption is "reachable via `Lorentz_abs_CW` through pycrysfml" is
+**not true today** — it would require upstream wrapping or an upstream
+call-site change we do not control.
+
+**cryspy** has **no absorption code at all** (only Debye–Waller and
+sphere _extinction_, which are different physics). CW intensity is
+assembled in `procedure_rhochi/rhochi_pd.py` as
+`0.5 · scale · Lorentz(θ) · |F|² · mult`, with no slot for an A(θ)
+factor.
+
+### Consequence of the source survey
+
+Neither backend can apply the correction internally without changes we
+do not own. The only way to get **identical** results across both
+calculators is to compute A(θ) **ourselves in EasyDiffraction** and
+apply it to the calculated pattern. This makes absorption a
+**calculator-independent** correction — unlike `extinction`, which is
+threaded into cryspy's own dict and is therefore `cryspy`-only.
+
+### CIF dictionary support (`tmp/iucr-dicts`)
+
+There is **no** standard data name for μR or for the Hewat coefficient.
+The standard items cover the _physical provenance_ only:
+
+| Quantity                  | Standard CIF item                                             | Units |
+| ------------------------- | ------------------------------------------------------------- | ----- |
+| Linear absorption μ       | `_exptl_absorpt.coefficient_mu`, `_pd_char.atten_coef_mu_*`   | mm⁻¹  |
+| Sample radius / thickness | `_pd_spec.size_axial/_equat/_thick`                           | mm    |
+| Sample shape              | `_pd_spec.shape` ∈ {`cylinder`, `flat_sheet`, `irregular`}    | code  |
+| Correction type           | `_exptl_absorpt.correction_type` (incl. `cylinder`, `sphere`) | code  |
+| Beam path                 | `_pd_spec.mount_mode` ∈ {`reflection`, `transmission`}        | code  |
+
+So the refineable μR itself needs a **project-namespaced**
+(`_easydiffraction_absorption.*`) tag, with the standard items available
+later as optional provenance (see Deferred Work).
+
+### Evidence from the FullProf example suite
+
+A survey of all 68 `.pcr` files shipped with FullProf (`Examples/`)
+shows that **every** absorption example — CW and TOF — is **cylindrical
+(Debye–Scherrer)**; not one uses flat-plate or exponential absorption,
+and the container term is never used:
+
+- **CW (cylindrical `muR`):** `dy*`, `DyMnGe*`, `cuf1k`, `hocu`,
+  `si3n4r`, `sin_3t2` — μR ∈ {0.068, 0.15, 0.40, 1.28}, all **fixed**
+  (no refinement codeword on the Lambda line). Note μR reaches **1.28**,
+  slightly past Hewat's nominal ≈1.0 validity — the practical motivation
+  for the Lobanov form later.
+- **TOF (`Iabscor`):** `Ceo2_PEARL`, `nac-osiris(n)`, `hrpd`, `arg_si`,
+  `cecual`, `cecoal`, `lamn_pol` — **all `Iabscor = 2` (cylindrical)**,
+  with `ABSCOR1` non-zero and **refined** (non-zero codewords).
+- **Never observed:** `Iabscor = 1` (flat plate), `Iabscor = 3`
+  (exponential), or a non-zero `2nd-muR` (container) in any file.
+
+Two design consequences:
+
+1. **Ship a single cylindrical type now.** The cylinder is the only
+   geometry the reference toolchain actually exercises, so Phase 1
+   builds `none` + `cylinder-hewat` only; everything else becomes a
+   documented future extension (§Deferred Work) that plugs into the same
+   switchable category without rework.
+2. **Refineable, default-fixed.** CW practice fixes `muR`; TOF practice
+   refines it. So `mu_r` is a normal refineable `Parameter` but ships
+   `free = False` (matching the CW reference and the Biso degeneracy),
+   not a constant.
+
+## Decision
+
+### 1. Add a switchable `absorption` category on the experiment
+
+Introduce `experiment.absorption`, mirroring `experiment.extinction`: a
+`SwitchableCategoryBase` whose concrete classes are registered with an
+`AbsorptionFactory`, gated by `Compatibility` and `CalculatorSupport`.
+It follows
+[`switchable-category-owned-selectors.md`](../accepted/switchable-category-owned-selectors.md):
+
+```python
+experiment.absorption.type             # writable selector (str)
+experiment.absorption.show_supported() # supported types, active starred
+```
+
+The owner exposes only `experiment.absorption` and a private
+`_swap_absorption` hook (Family A: the hook **replaces the category
+instance** when `type` changes), exactly as `extinction` does today.
+
+### 2. Application point — a pointwise envelope on the calculated pattern
+
+Because A(θ) is a **slowly-varying smooth envelope** of sin²θ (its
+fractional change across one peak FWHM is ≪ 1 for any realistic μR),
+applying it per-reflection vs. pointwise to the summed pattern differs
+only at second order in (FWHM · dA/dθ) — negligible. We therefore apply
+it once, after pattern assembly, in **both** backends:
+
+```
+y_corrected(2θ_i) = A(θ_i) · y_calc(2θ_i)
+```
+
+This is a single shared helper
+(`analysis/calculators/absorption.py::factor(two_theta, params)`) called
+from the post-calculation step of both `cryspy.py` and `crysfml.py`. The
+two backends thus stay bit-for-bit consistent on the absorption term,
+and the helper is unit-testable in isolation against FullProf output
+(validated to 4 decimals in the issue).
+
+### 3. Supported types — the taxonomy
+
+The `type` selector lists factory tags gated by `Compatibility` (sample
+form, beam mode, scattering type, radiation) and `CalculatorSupport`.
+**Phase 1 builds only the first two rows;** the rest are the planned
+extension surface, designed here so they later plug into the same
+category by registering a class (see Deferred Work).
+
+| Tag                | Beam mode | Sample form | Radiation     | Calculators     | Parameters      | Status      |
+| ------------------ | --------- | ----------- | ------------- | --------------- | --------------- | ----------- |
+| `none`             | any       | any         | neutron, xray | cryspy, crysfml | —               | **Phase 1** |
+| `cylinder-hewat`   | CWL       | powder      | neutron, xray | cryspy, crysfml | `mu_r`          | **Phase 1** |
+| `cylinder-lobanov` | CWL       | powder      | neutron, xray | cryspy, crysfml | `mu_r`          | future      |
+| `tof-cylinder`     | TOF       | powder      | neutron       | cryspy, crysfml | `mu_r` (λ-dep.) | future      |
+| `flat-plate`       | CWL       | powder      | neutron, xray | cryspy, crysfml | `mu_t`          | future      |
+| `tof-exponential`  | TOF       | powder      | neutron       | cryspy, crysfml | `coeff`, `exp`  | future      |
+
+Notes:
+
+- `none` is the **default** (A ≡ 1). The category always exists for
+  powder so the user can discover and switch it on via
+  `show_supported()`; opting out is `type = 'none'`, not deleting the
+  category. (`scattering_type = 'total'` / pdffit is out of scope.)
+- **Why a single built type is correct now:** the FullProf example suite
+  uses only cylindrical absorption (§"Evidence from the FullProf example
+  suite"), and our sole verification reference is CW cylindrical (LaB₆,
+  μR = 0.7). Building `cylinder-hewat` alone closes the known gap with a
+  tested oracle; the others would ship untested physics. This also
+  respects [`AGENTS.md`](../../../../AGENTS.md) §Architecture ("don't
+  introduce abstractions before a concrete second use case") — but the
+  switchable-category contract is still required even for a single
+  implementation (as `extinction` is today with only `becker-coppens`),
+  which is what keeps the extension surface free.
+- Radiation is **not** a discriminator for the cylindrical geometric
+  envelope — the Hewat/Lobanov constants depend on geometry, not on
+  neutron vs X-ray. X-ray simply tends to larger μ; the same formula
+  applies. Both are supported.
+- The future rows are designed (tags, parameters, CIF) but **not
+  built**. TOF in particular is λ-dependent and the slow-envelope
+  argument does not carry over unchanged (each detector bin mixes
+  wavelengths), so it needs its own application path; it is listed so
+  the taxonomy and CIF tags are settled once.
+
+### 4. The μR parameter
+
+The single refineable/settable quantity is **`mu_r`** (μ·R), matching
+FullProf's `muR` and CrysFML's `tmv`. It is a `Parameter`
+(`RangeValidator(ge=0.0)`, default `0.0`), **free=False by default**
+(absorption is normally fixed, per the LaB₆ reference). Storing μ and R
+separately is rejected (see Alternatives); they can be added later as
+read-only provenance (Deferred Work).
+
+`flat-plate` uses `mu_t` (μ·thickness); the TOF exponential form uses
+`coeff` and `exp` (`A = exp(−coeff·λ^exp)`).
+
+### 5. Equations
+
+**Hewat** (cylinder, validated to 4 decimals vs FullProf; fit range μR ≲
+1.5):
+
+```
+A(θ) = exp( −(1.7133 − 0.0368·sin²θ)·μR + (0.0927 + 0.375·sin²θ)·μR² )
+```
+
+**Lobanov–Alte da Veiga** (cylinder, extends to μR ≈ 10 via a branch at
+μR = 3; `s ≡ sinθ`):
+
+```
+μR ≤ 3:
+  k1 = (25.99978 − 0.01911·s^0.25)·exp(−0.024514·s) + 0.109561·√s − 26.0456
+  k2 = −0.02489 − 0.39499·s + 1.219077·s^1.5 − 1.31268·s² + 0.871081·s^2.5 − 0.2327·s³
+  k3 =  0.003045 + 0.018167·s − 0.03305·s²
+  A  = exp( −((k3·μR + k2)·μR + k1)·μR )      (normalised; k0 = 1.697653)
+
+μR > 3:
+  A  = k7 + (k4 − k7) / (1 + k5·(μR − 3))^k6   (k4…k7 polynomials in s)
+```
+
+(Lobanov constants transcribed from CrysFML08
+`Pow_Lorentz_Absorption.f90`; the implementation will copy them verbatim
+and unit-test against that source.)
+
+**Flat plate, symmetric θ–2θ** (μt = μ·thickness):
+
+```
+A(θ) = exp( −2·μt / sinθ )            # transmission, symmetric reflection
+```
+
+**TOF exponential** (deferred; per FullProf `Iabscor = 3`):
+
+```
+A(λ) = exp( −coeff · λ^exp )
+```
+
+### 6. User-facing API
+
+```python
+# Discover what is available for this experiment (Phase 1)
+experiment.absorption.show_supported()
+# -> none (*), cylinder-hewat
+
+# Turn on the cylindrical Debye–Scherrer correction
+experiment.absorption.type = 'cylinder-hewat'
+experiment.absorption.mu_r = 0.7          # fixed value from the beamline
+
+# (Optional) refine it — off by default because it is near-degenerate
+# with Biso and scale
+experiment.absorption.mu_r.free = True
+```
+
+`experiment.absorption.type = 'none'` restores A ≡ 1.
+
+### 7. CIF mapping
+
+Project-namespaced block, one identity tag plus the magnitude:
+
+```
+_absorption.type   cylinder-hewat
+_absorption.mu_r   0.7
+```
+
+IUCr-aligned export (per
+[`iucr-cif-tag-alignment.md`](../accepted/iucr-cif-tag-alignment.md))
+uses `_easydiffraction_absorption.type` / `.mu_r`, and may additionally
+emit the standard provenance `_exptl_absorpt.correction_type cylinder`.
+`flat-plate` writes `_absorption.mu_t`; TOF forms write their own
+fields. The `_absorption.type` tag is the single source of truth for the
+active type (no owner-level selector tag), per
+[`switchable-category-owned-selectors.md`](../accepted/switchable-category-owned-selectors.md).
+
+### 8. Cost
+
+A(θ) is one vectorised `exp` over the 2θ grid per pattern evaluation —
+microseconds, utterly dominated by the diffraction calculation itself.
+Refining `mu_r` adds one parameter; each fit iteration recomputes the
+envelope at negligible cost. There is no per-reflection loop and no
+backend round-trip.
+
+## Consequences
+
+- **Closes the LaB₆ absorption residual.** The
+  `pd-neut-cwl_tch-fcj_abs_lab6` verification page becomes the
+  acceptance test: with `cylinder-hewat`, `mu_r = 0.7` it should reach
+  the same corr as the μR = 0 page.
+- **Calculator-consistent by construction.** Both backends call the same
+  helper, so the absorption term can never drift between `cryspy` and
+  `crysfml`. New backends inherit it for free.
+- **No upstream dependency.** We do not wait on cryspy or CrysFML Python
+  wrappers; nothing in `pyproject.toml` changes.
+- **New switchable category to wire.** Owner attribute, `_swap_*` hook,
+  factory, `__init__.py` registration, enums, CIF round-trip, and the
+  `none` default — the full
+  [`switchable-category-owned-selectors.md`](../accepted/switchable-category-owned-selectors.md)
+  surface. Mitigated by mirroring `extinction` closely.
+- **Degeneracy is documented, not hidden.** `mu_r.free = False` by
+  default; help text warns that refining μR together with Biso/scale
+  correlates strongly. Explicit modelling is preferred precisely so Biso
+  is not biased by soaking up absorption.
+- **Pointwise envelope is an approximation** (second order in
+  FWHM·dA/dθ). Validated to 4 decimals against FullProf; acceptable and
+  documented.
+
+## Alternatives Considered
+
+1. **Per-reflection multiply inside each backend.** More "correct" in
+   principle, but cryspy has no slot (would need to patch its intensity
+   loop) and crysfml's routine is in unwrapped Fortran. Two divergent
+   code paths, an upstream dependency, and no measurable accuracy gain
+   over the envelope. Rejected.
+2. **Flat instrument parameter `instrument.mu_r`** (as the issue
+   sketches). Simpler, but it cannot carry a correction-type selector
+   (Hewat vs Lobanov vs flat-plate vs TOF), breaks the
+   switchable-category uniformity the project standardised on, and has
+   no natural home for TOF forms. Rejected in favour of the switchable
+   category.
+3. **Store μ and R separately, compute μR.** Matches the CIF items, but
+   the two inputs are perfectly correlated for the correction and only
+   their product matters; FullProf and CrysFML both parametrise by the
+   product. Storing them separately invites a confusing two-knob UI for
+   one degree of freedom. Deferred to optional provenance.
+4. **Let Biso absorb it.** The status quo. Biases the thermal parameters
+   and fails the `_abs_` verification page. Rejected — this ADR exists
+   to avoid exactly that.
+
+## Deferred Work
+
+All of these are designed into the taxonomy and CIF tags above but **not
+built in Phase 1** — each is a new class registered on the same
+`AbsorptionFactory`, gated by `Compatibility`/`CalculatorSupport`, with
+no change to the category, the swap hook, or the application helper.
+None appears in the FullProf example suite (only the cylinder does), so
+none is urgent; each should land **with a verification dataset**, not on
+spec alone.
+
+- **`cylinder-lobanov`** — extends valid μR to ≈10 (branch at μR = 3).
+  Real CW neutron examples reach μR = 1.28, past Hewat's ≈1.0 validity,
+  so this is a genuine eventual want, not hypothetical. Add when a
+  high-μR reference exists; Hewat alone meets the current LaB₆ case.
+- **TOF absorption** (`tof-cylinder`, `tof-exponential`): the
+  λ-dependent forms (FullProf `Iabscor = 2 / 3`). The pointwise-2θ
+  envelope does not transfer directly — needs its own application path.
+  FullProf TOF examples all use `Iabscor = 2` (cylindrical) and refine
+  it, so `tof-cylinder` is the natural next target.
+- **`flat-plate`** (CW symmetric θ–2θ, `mu_t`) and other geometries
+  (`Iabscor = 1`): present in the file formats but used by **zero**
+  FullProf examples — lowest priority.
+- **Optional (μ, R) provenance** mapped to
+  `_exptl_absorpt.coefficient_mu` and `_pd_spec.size_*`, read-only, with
+  `mu_r` remaining the single refineable knob.
+- **Container / `2nd-muR`** (sample-in-holder coaxial cylinder): never
+  used in any FullProf example; revisit only if a case needs it.
+- **Single-crystal absorption** (different formalism entirely).
diff --git a/docs/dev/issues/open.md b/docs/dev/issues/open.md
index 8477f9203..76634fe41 100644
--- a/docs/dev/issues/open.md
+++ b/docs/dev/issues/open.md
@@ -31,19 +31,30 @@ A(θ) = exp( -(1.7133 − 0.0368·sin²θ)·μR + (0.0927 + 0.375·sin²θ)·μR
 
 A Lobanov–Alte-da-Veiga form covers `μR > 3`.
 
-**Implementation sketch:**
-
-- Add a `μR` instrument parameter for CWL powder (Debye–Scherrer).
-- `crysfml`: CrysFML08 already implements this — reachable via
-  `Lorentz_abs_CW(..., ilor='DBS', cabs='HEWAT', tmv=μR)` through
-  pycrysfml.
-- `cryspy`: multiply each reflection's intensity by `A(θ_hkl)`,
-  analogous to the existing Lorentz factor (one extra term).
+**Design:** captured in
+[`adrs/suggestions/model-sample-absorption.md`](../adrs/suggestions/model-sample-absorption.md)
+— a switchable `experiment.absorption` category (mirroring `extinction`)
+with a calculator-independent A(θ) envelope.
+
+**What the backends actually provide (corrected):**
+
+- `cryspy`: **no** absorption code at all (only Debye–Waller and sphere
+  _extinction_); its CW intensity loop has no slot to multiply A(θ).
+- `crysfml`: CrysFML08 implements `Lorentz_abs_CW` in Fortran, but it is
+  **not** wrapped in `PythonAPI/`, and the high-level
+  `cw_powder_pattern_from_dict` path we call applies a plain Lorentz
+  factor with no absorption. So it is **not** reachable through
+  pycrysfml today without upstream changes.
+
+**Implication:** neither backend can apply the correction internally
+without changes we do not own. The chosen approach computes A(θ) in
+EasyDiffraction and applies it as a pointwise envelope on the calculated
+pattern, identically for both calculators (see the ADR).
 
 **Note:** absorption is nearly degenerate with Biso + scale (its angle
 term is linear in `sin²θ`, like the Debye–Waller), so refining Biso can
 partly absorb it — but that biases Biso, so an explicit correction is
-preferable.
+preferable. In FullProf `μR` is normally **fixed**, not refined.
 
 **References:**
 
@@ -52,10 +63,16 @@ preferable.
 - CrysFML08:
   [`Src/CFML_Powder/Pow_Lorentz_Absorption.f90`](https://code.ill.fr/scientific-software/CrysFML2008/-/blob/master/Src/CFML_Powder/Pow_Lorentz_Absorption.f90),
   `Lorentz_abs_CW`.
-- FullProf `μR`: `.pcr` Lambda line field 7; `iabscor = 2` selects
-  HEWAT.
+- FullProf splits absorption into a refineable **magnitude** and a
+  **type**: CW uses `μR` on the `.pcr` Lambda line (fixed there — no
+  refinement codeword), with the cylindrical Hewat form implied; TOF
+  uses `Iabscor` (`1` flat plate, `2` cylinder, `3` exponential
+  `exp(−ABS·λᶜ)`). `Cthm`/`Rpolarz`/`2nd-muR` on the Lambda line are
+  polarization and container terms, not the primary absorption knob.
 
-**Depends on:** adding a `μR` instrument parameter.
+**Depends on:** the switchable `experiment.absorption` category in the
+ADR above (supersedes the earlier "add a `μR` instrument parameter"
+sketch).
 
 ---
 
@@ -2041,7 +2058,7 @@ The fast docs gate (`docs-build` + `link-check` + `spell-check`) catches
 broken nav/internal links and typos on every push, but does not yet
 check external URLs. Add a `lychee` link checker (with an allowlist for
 rate-limited/unstable domains), coordinated with the
-[Documentation CI and Build Verification](../adrs/suggestions/documentation-ci-build.md)
+[Documentation CI and Build Verification](../adrs/accepted/documentation-ci-build.md)
 ADR. Run it nightly or on pull requests to avoid flakiness from external
 sites. Also covers link-checking of URLs that appear only inside
 executed notebook output cells (a feature that does not exist yet).
diff --git a/docs/dev/issues/recommended-priorities.md b/docs/dev/issues/recommended-priorities.md
index a70b716de..9c8457024 100644
--- a/docs/dev/issues/recommended-priorities.md
+++ b/docs/dev/issues/recommended-priorities.md
@@ -83,7 +83,7 @@ session:
 - **[`cif-numeric-precision.md`](../adrs/suggestions/cif-numeric-precision.md)**
   — s.u.-aware CIF serialization (file size + meaningful precision).
 - **[`fit-output-files-and-data-exports.md`](../adrs/suggestions/fit-output-files-and-data-exports.md)**.
-- **[`documentation-ci-build.md`](../adrs/suggestions/documentation-ci-build.md)**.
+- **[`documentation-ci-build.md`](../adrs/accepted/documentation-ci-build.md)**.
 - **[`in-house-calculation-engine.md`](../adrs/suggestions/in-house-calculation-engine.md)**
   — drafted 2026-06-10 (in review): own the core (neutron powder
   Rietveld) in-repo, keep cryspy/crysfml/pdffit for the frontier.
diff --git a/docs/dev/plans/documentation-snippet-tests.md b/docs/dev/plans/documentation-snippet-tests.md
new file mode 100644
index 000000000..63d80ec77
--- /dev/null
+++ b/docs/dev/plans/documentation-snippet-tests.md
@@ -0,0 +1,210 @@
+# Plan: Documentation snippet smoke tests
+
+This plan follows [`AGENTS.md`](../../../AGENTS.md). No deliberate
+exceptions to those instructions are required.
+
+## ADR
+
+Implements decision 3 ("Add snippet smoke tests for user-facing
+examples") of the accepted ADR
+[`documentation-ci-build.md`](../adrs/accepted/documentation-ci-build.md).
+No new ADR is required. The ADR's "Implementation Status" table marks
+this decision as the highest-value remaining gap, and its "Deferred
+Work" section points at this plan.
+
+## Motivation
+
+User-facing code snippets drift from the public API. A recent pass found
+`from easydiffraction import Structure / Experiment` (neither exported)
+and `download_from_repository(...)` (does not exist) live in
+`user-guide/first-steps.md`. The strict MkDocs build and link checker do
+not execute Python, so this class of breakage reaches readers. A small,
+fast, backend-free smoke test that exercises the documented public API
+shape would catch it before merge.
+
+## Branch and PR
+
+- Branch: `documentation-snippet-tests` (flat slug, off `develop`).
+  Created and checked out by `/draft-impl-1`.
+- PR targets `develop`, not `master`. Do not push unless asked.
+
+## Decisions
+
+- **Explicit markers, not blanket extraction.** Only fenced
+  ` ```python ` blocks explicitly opted in are executed. Many documented
+  snippets are intentionally non-self-contained (they reference a
+  `project` built in an earlier block, download data, or run `fit()`
+  against a real backend); auto-running every block would force heavy
+  fixtures and network/backends, which the ADR rules out. The opt-in
+  marker is an HTML comment on the line immediately before the fence:
+  `<!-- api-shape-test -->`. This keeps the test set curated and the
+  intent visible in the source Markdown.
+- **API shape only, no computation.** Marked snippets construct small
+  in-memory objects and assert public names exist (`Project()`,
+  `project.structures.create(...)`, `experiment.peak.type = ...`,
+  `project.analysis.minimizer.show_supported()`,
+  `project.display.parameters.all()`). They must not download data, run
+  `fit()`, or select a real calculator/sampler backend.
+- **No network, no real backends, no notebooks.** The runner sets a
+  guard (monkeypatched `download_data`/`download_tutorial` that raise,
+  and a check that no marked snippet imports a calculator backend).
+  Snippets run in a unique temp working directory.
+- **Test tier: `tests/functional/`.** These are fast, in-process,
+  backend-free checks of the public API as documented — the same tier as
+  the existing functional suite (`pixi run functional-tests`, no
+  `-n auto`, no backends). They are not unit tests (they do not mirror a
+  single `src/` module) and not integration tests (no network/backends),
+  so `tests/unit/` structure mirroring (`test-structure-check`) is
+  unaffected.
+- **One always-on shape check, independent of markers.** In addition to
+  marked-snippet execution, a parametrised test scans the doc set for
+  `from easydiffraction import <name>` and `ed.<name>` references and
+  asserts each resolves against the installed package. This alone would
+  have caught the `first-steps.md` regression and needs no per-snippet
+  curation.
+- **Scope of pages (initial).** Per the ADR:
+  `docs/docs/quick-reference/index.md`,
+  `docs/docs/user-guide/first-steps.md`,
+  `docs/docs/user-guide/analysis-workflow/*.md`. Expandable later.
+
+## Open questions
+
+- Marker syntax: `<!-- api-shape-test -->` HTML comment (recommended,
+  invisible in rendered docs) vs. a fenced info string like
+  ` ```python title="api-shape-test" `. Recommendation: HTML comment.
+  Confirm during `/draft-impl-1`.
+- Whether to wire the new pixi task into the `lint-format.yml` gate now
+  or fold it into `functional-tests` (already in `pixi run all` and the
+  test workflow). Recommendation: fold into `functional-tests` so no CI
+  wiring change is needed; add a thin `docs-snippet-tests` alias for
+  local runs.
+
+## Concrete files likely to change
+
+- New: `tests/functional/test_docs_snippets.py` — the runner: snippet
+  extraction (reuse the Markdown-walking style of
+  `tools/test_scripts.py` and the skip-list pattern of
+  `docs/docs/conftest.py`), the marked-snippet execution test, and the
+  always-on import-shape test.
+- New (optional): a tiny helper module if extraction logic is shared,
+  e.g. `tests/functional/_docs_snippets.py`.
+- `pixi.toml` — add a `docs-snippet-tests` convenience task (and, per
+  the open question, optionally have `functional-tests` already cover
+  it).
+- `docs/docs/quick-reference/index.md`,
+  `docs/docs/user-guide/first-steps.md`,
+  `docs/docs/user-guide/analysis-workflow/*.md` — add
+  `<!-- api-shape-test -->` markers above the curated safe snippets;
+  make minimal edits only where a snippet must be self-contained to run.
+- `docs/dev/adrs/accepted/documentation-ci-build.md` — flip decision 3
+  in the Implementation Status table from "Not done" to "Done" and drop
+  the matching Deferred Work bullet (final Phase 1 step before the
+  gate).
+
+## Implementation steps (Phase 1)
+
+Each `- [ ]` step is one atomic commit. An AI agent following this plan
+must edit the checkbox to `- [x]`, stage the listed files with explicit
+paths, and commit locally with the step's `Commit:` line **before**
+moving to the next step (per AGENTS.md → Commits). Do not create or run
+the test suite as a debugging tool during Phase 1; Phase 2 owns
+verification.
+
+- [ ] **P1.1 — Add the import-shape test (always-on).** Create
+      `tests/functional/test_docs_snippets.py` with the doc-page list
+      and a parametrised test that extracts every
+      `from easydiffraction import <name>` and `ed.<name>` reference
+      from the listed pages and asserts each name resolves on the
+      installed `easydiffraction` package. Files:
+      `tests/functional/test_docs_snippets.py`. Commit:
+      `Add import-shape smoke test for doc snippets`
+
+- [ ] **P1.2 — Add the marked-snippet extractor and runner.** Extend the
+      test module to collect ` ```python ` blocks preceded by
+      `<!-- api-shape-test -->`, and exec each page's marked blocks in a
+      shared namespace inside a unique temp cwd, with `download_data` /
+      `download_tutorial` monkeypatched to raise and a guard rejecting
+      any real-backend selection. No snippets are marked yet, so the
+      test is a no-op collection at this point. Files:
+      `tests/functional/test_docs_snippets.py` (+ optional
+      `tests/functional/_docs_snippets.py`). Commit:
+      `Add marked-snippet runner for doc smoke tests`
+
+- [ ] **P1.3 — Mark and (minimally) adapt Quick Reference snippets.**
+      Add `<!-- api-shape-test -->` to the backend-free, self-contained
+      snippets in `quick-reference/index.md` (session start,
+      build-a-project in code, show/select-type blocks). Make the
+      smallest edits needed for them to run standalone; do not change
+      documented behaviour. Files: `docs/docs/quick-reference/index.md`,
+      `tests/functional/test_docs_snippets.py` (if fixtures needed).
+      Commit: `Mark Quick Reference snippets for smoke testing`
+
+- [ ] **P1.4 — Mark and adapt First Steps and Analysis Workflow
+      snippets.** Same treatment for `user-guide/first-steps.md` and
+      `user-guide/analysis-workflow/*.md`. Files:
+      `docs/docs/user-guide/first-steps.md`,
+      `docs/docs/user-guide/analysis-workflow/*.md`. Commit:
+      `Mark user-guide snippets for smoke testing`
+
+- [ ] **P1.5 — Add the `docs-snippet-tests` pixi task.** Add a
+      convenience task running the new file (e.g.
+      `docs-snippet-tests = 'python -m pytest tests/functional/test_docs_snippets.py --color=yes -v'`).
+      Confirm the open question on `functional-tests` coverage; if
+      folding in, no workflow change is required. Files: `pixi.toml`.
+      Commit: `Add docs-snippet-tests pixi task`
+
+- [ ] **P1.6 — Update the ADR Implementation Status.** In
+      `documentation-ci-build.md`, flip decision 3 to "Done" with a
+      pointer to the new task, and remove the snippet-tests bullet from
+      Deferred Work. Files:
+      `docs/dev/adrs/accepted/documentation-ci-build.md`. Commit:
+      `Mark snippet smoke tests done in documentation-ci-build ADR`
+
+- [ ] **P1.7 — Phase 1 review gate (no code).** Mark this item `[x]` and
+      commit the checklist update alone. Commit:
+      `Reach Phase 1 review gate`
+
+## Verification (Phase 2)
+
+Run after Phase 1 review. Capture logs with the zsh-safe pattern where
+output is needed for analysis.
+
+```bash
+pixi run fix
+pixi run check > /tmp/easydiffraction-check.log 2>&1; check_exit_code=$?; tail -n 200 /tmp/easydiffraction-check.log; exit $check_exit_code
+pixi run unit-tests
+pixi run functional-tests > /tmp/easydiffraction-functional.log 2>&1; functional_tests_exit_code=$?; tail -n 200 /tmp/easydiffraction-functional.log; exit $functional_tests_exit_code
+pixi run integration-tests
+pixi run script-tests
+```
+
+Expectations:
+
+- `pixi run functional-tests` (covering the new
+  `tests/functional/test_docs_snippets.py`) passes, and the import-shape
+  test fails loudly if a documented symbol is later removed or renamed.
+- `pixi run check` stays clean, including `spell-check`, `link-check`,
+  and the strict docs build.
+
+## Status checklist
+
+- [ ] P1.1 Import-shape test
+- [ ] P1.2 Marked-snippet runner
+- [ ] P1.3 Quick Reference snippets marked
+- [ ] P1.4 User-guide snippets marked
+- [ ] P1.5 `docs-snippet-tests` pixi task
+- [ ] P1.6 ADR Implementation Status updated
+- [ ] P1.7 Phase 1 review gate
+- [ ] Phase 2 verification complete
+
+## Suggested Pull Request
+
+**Title:** Catch broken code examples in the documentation automatically
+
+**Description:** EasyDiffraction now checks its own documentation: a
+fast test confirms that the Python commands shown in the Quick
+Reference, First Steps, and Analysis Workflow pages still match the
+current software. If a future change renames or removes something used
+in an example, the check fails before the documentation goes out, so the
+commands you copy from the guides keep working. The check runs entirely
+offline and does not perform any real calculations, so it stays quick.
diff --git a/docs/docs/index.md b/docs/docs/index.md
index f3f434005..f0b4404f6 100644
--- a/docs/docs/index.md
+++ b/docs/docs/index.md
@@ -16,6 +16,9 @@ Here is a brief overview of the main documentation sections:
 - [:material-school: Tutorials](tutorials/index.md) – Offers practical,
   step-by-step examples demonstrating common workflows and data analysis
   tasks.
+- [:material-check-decagram: Verification](verification/index.md) –
+  Cross-checks EasyDiffraction calculations against reference results
+  from external software (FullProf) across supported experiment types.
 - [:material-console: Command-Line Interface](cli/index.md) – Describes
   how to use EasyDiffraction from the terminal for batch fitting and
   other tasks.
diff --git a/docs/docs/tutorials/index.md b/docs/docs/tutorials/index.md
index cfb3da1dd..64511d5a0 100644
--- a/docs/docs/tutorials/index.md
+++ b/docs/docs/tutorials/index.md
@@ -83,10 +83,10 @@ containing Bayesian fit state.
 
 ## Single Crystal Diffraction
 
-- [Tb2TiO7 `sg-neut-cwl`](ed-14.ipynb) – Demonstrates structure
+- [Tb2TiO7 `sc-neut-cwl`](ed-14.ipynb) – Demonstrates structure
   refinement of Tb2TiO7 using constant wavelength neutron single crystal
   diffraction data from HEiDi at FRM II.
-- [Taurine `sg-neut-tof`](ed-15.ipynb) – Demonstrates structure
+- [Taurine `sc-neut-tof`](ed-15.ipynb) – Demonstrates structure
   refinement of Taurine using time-of-flight neutron single crystal
   diffraction data from SENJU at J-PARC.
 
diff --git a/docs/docs/user-guide/analysis-workflow/analysis.md b/docs/docs/user-guide/analysis-workflow/analysis.md
index 3819765b7..c3a71d747 100644
--- a/docs/docs/user-guide/analysis-workflow/analysis.md
+++ b/docs/docs/user-guide/analysis-workflow/analysis.md
@@ -392,8 +392,8 @@ for Ba will be equal to that of La during the refinement process.
 
 ### Viewing Constraints
 
-To view the defined constraints, you can use the `show_constraints`
-method:
+To view the defined constraints, you can use the `show` method on
+`project.analysis.constraints`:
 
 ```python
 project.analysis.constraints.show()
diff --git a/docs/docs/user-guide/data-format.md b/docs/docs/user-guide/data-format.md
index d81346f1c..9b8b505e1 100644
--- a/docs/docs/user-guide/data-format.md
+++ b/docs/docs/user-guide/data-format.md
@@ -62,7 +62,7 @@ isotropic displacement parameters (_Biso_)
 | Label | Type | x   | y   | z   | occ | Biso   |
 | ----- | ---- | --- | --- | --- | --- | ------ |
 | La    | La   | 0   | 0   | 0   | 0.5 | 0.4958 |
-| Ba    | Ba   | 0   | 0   | 0   | 0.5 | 0.4958 |
+| Ba    | Ba   | 0   | 0   | 0   | 0.5 | 0.4943 |
 | Co    | Co   | 0.5 | 0.5 | 0.5 | 1.0 | 0.2567 |
 | O     | O    | 0   | 0.5 | 0.5 | 1.0 | 1.4041 |
 
@@ -97,7 +97,7 @@ loop_
 <span class="green"><b>_atom_site</b>.ADP_type</span>
 <span class="green"><b>_atom_site</b>.B_iso_or_equiv</span>
 La La   0   0   0     a   0.5  Biso 0.4958
-Ba Ba   0   0   0     a   0.5  Biso 0.4958
+Ba Ba   0   0   0     a   0.5  Biso 0.4943
 Co Co   0.5 0.5 0.5   b   1    Biso 0.2567
 O  O    0   0.5 0.5   c   1    Biso 1.4041
 </pre>
diff --git a/docs/docs/user-guide/first-steps.md b/docs/docs/user-guide/first-steps.md
index 81e901c70..e8f235e46 100644
--- a/docs/docs/user-guide/first-steps.md
+++ b/docs/docs/user-guide/first-steps.md
@@ -37,14 +37,14 @@ A complete tutorial using the `import` syntax can be found
 ### Importing specific parts
 
 Alternatively, you can import specific classes or methods from the
-package. For example, you can import the `Project`, `Structure`,
-`Experiment` classes and `download_from_repository` method like this:
+package. For example, you can import the `Project`, `StructureFactory`,
+`ExperimentFactory` classes and `download_data` method like this:
 
 ```python
 from easydiffraction import Project
-from easydiffraction import Structure
-from easydiffraction import Experiment
-from easydiffraction import download_from_repository
+from easydiffraction import StructureFactory
+from easydiffraction import ExperimentFactory
+from easydiffraction import download_data
 ```
 
 This enables you to use these classes and methods directly without the
@@ -62,28 +62,26 @@ A complete tutorial using the `from` syntax can be found
 ## Utility functions
 
 EasyDiffraction also provides several utility functions that can
-simplify your workflow. One of them is the `download_from_repository`
-function, which allows you to download data files from our remote
-repository, making it easy to access and use them while experimenting
-with EasyDiffraction.
+simplify your workflow. One of them is the `download_data` function,
+which allows you to download example datasets by their numeric ID from
+our remote repository, making it easy to access and use them while
+experimenting with EasyDiffraction.
 
-For example, you can download a data file like this:
+You can list the available datasets and their IDs with `list_data()`,
+then download one like this:
 
 ```python
 import easydiffraction as ed
 
-ed.download_from_repository(
-    'hrpt_lbco.xye',
-    branch='docs',
-    destination='data',
-)
+ed.list_data()
+
+data_path = ed.download_data(id=3, destination='data')
 ```
 
-This command will download the `hrpt_lbco.xye` file from the `docs`
-branch of the EasyDiffraction repository and save it in the `data`
-directory of your current working directory. This is particularly useful
-for quickly accessing example datasets without having to manually
-download them.
+This command downloads the dataset with ID `3` and saves it in the
+`data` directory of your current working directory, returning the full
+path to the downloaded file. This is particularly useful for quickly
+accessing example datasets without having to manually download them.
 
 ## Help methods
 
diff --git a/docs/docs/user-guide/glossary.md b/docs/docs/user-guide/glossary.md
index 75f0300c0..16bf0e4f2 100644
--- a/docs/docs/user-guide/glossary.md
+++ b/docs/docs/user-guide/glossary.md
@@ -36,7 +36,7 @@ experiment types:
 
 ### X-ray Diffraction
 
-- [pd-xray][0]{:.label-experiment} Powder X-ray diffraction.
+- [pd-xray][0]{:.label-experiment} – Powder X-ray diffraction.
 
 <!-- prettier-ignore-start -->
 [0]: #
diff --git a/docs/docs/verification/ci_skip.txt b/docs/docs/verification/ci_skip.txt
index e64d34537..0c1e04bdc 100644
--- a/docs/docs/verification/ci_skip.txt
+++ b/docs/docs/verification/ci_skip.txt
@@ -19,4 +19,4 @@ pd-neut-cwl_tch-fcj-noabs_lab6  # FCJ asymmetry (S_L/D_L) not implemented in cry
 pd-neut-cwl_tch-fcj_lab6  # unmodelled sample absorption (muR=0.7, HEWAT) + FCJ asymmetry; see issues/open.md
 pd-neut-tof_j_si  # ed-crysfml TOF Jorgensen profile ~8.5% off after fitting scale (area ratio 1.09, corr 0.997); cryspy matches FullProf
 pd-neut-tof_jvd_si  # cryspy TOF Lorentzian discrepancy; see issues/open.md
-sg-neut-cwl_ext-iso_tbti  # Different asymmetry types in cryspy vs FullProf
\ No newline at end of file
+sc-neut-cwl_ext-iso_tbti  # Different asymmetry types in cryspy vs FullProf
\ No newline at end of file
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.int b/docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.int
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.int
rename to docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.int
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.out b/docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.out
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.out
rename to docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.out
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.pcr b/docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.pcr
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.pcr
rename to docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.pcr
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.prf b/docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.prf
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.prf
rename to docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.prf
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.sum b/docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.sum
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_ext-iso_tbti/tbti.sum
rename to docs/docs/verification/fullprof/sc-neut-cwl_ext-iso_tbti/tbti.sum
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.int b/docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.int
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.int
rename to docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.int
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.out b/docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.out
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.out
rename to docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.out
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.pcr b/docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.pcr
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.pcr
rename to docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.pcr
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.prf b/docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.prf
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.prf
rename to docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.prf
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.sum b/docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.sum
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_noext_tbti/tbti.sum
rename to docs/docs/verification/fullprof/sc-neut-cwl_noext_tbti/tbti.sum
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.cif b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.cif
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.cif
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.cif
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.int b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.int
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.int
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.int
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.out b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.out
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.out
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.out
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.pcr b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.pcr
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.pcr
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.pcr
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.prf b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.prf
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.prf
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.prf
diff --git a/docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.sum b/docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.sum
similarity index 100%
rename from docs/docs/verification/fullprof/sg-neut-cwl_pr2nio4/prnio.sum
rename to docs/docs/verification/fullprof/sc-neut-cwl_pr2nio4/prnio.sum
diff --git a/docs/docs/verification/index.md b/docs/docs/verification/index.md
index f26badd1d..b1c61f093 100644
--- a/docs/docs/verification/index.md
+++ b/docs/docs/verification/index.md
@@ -29,7 +29,7 @@ effect; each such page states the reason below.
 
 Pages are grouped by **experiment type** (sample form, radiation probe,
 and beam mode). Coverage grows to span every supported combination —
-`pd-neut-cwl`, `pd-neut-tof`, `pd-xray`, `sg-neut-cwl`, `sg-neut-tof`,
+`pd-neut-cwl`, `pd-neut-tof`, `pd-xray`, `sc-neut-cwl`, `sc-neut-tof`,
 and so on. The list below notes only what is specific to each page.
 
 ## Powder, neutron, constant wavelength
@@ -72,15 +72,15 @@ and so on. The list below notes only what is specific to each page.
 
 ## Single crystal, neutron, constant wavelength
 
-- [Pr₂NiO₄ `sg-neut-cwl` (no extinction)](sg-neut-cwl_pr2nio4.ipynb) –
+- [Pr₂NiO₄ `sc-neut-cwl` (no extinction)](sc-neut-cwl_pr2nio4.ipynb) –
   Strontium-doped praseodymium nickelate (Pr₂NiO₄:Sr, K₂NiF₄-type,
   _Fmmm_); per-reflection F² against FullProf reference with anisotropic
   ADPs.
-- [Tb₂Ti₂O₇ `sg-neut-cwl` (no extinction)](sg-neut-cwl_noext_tbti.ipynb)
+- [Tb₂Ti₂O₇ `sc-neut-cwl` (no extinction)](sc-neut-cwl_noext_tbti.ipynb)
   – Terbium titanate (Tb₂Ti₂O₇, _F d -3 m_); per-reflection F² against a
   FullProf-no-extinction reference with anisotropic ADPs. Scale is
   initialized from the FullProf and refined.
-- [Tb₂Ti₂O₇ `sg-neut-cwl` (isotropic extinction)](sg-neut-cwl_ext-iso_tbti.ipynb)
+- [Tb₂Ti₂O₇ `sc-neut-cwl` (isotropic extinction)](sc-neut-cwl_ext-iso_tbti.ipynb)
   – Terbium titanate (Tb₂Ti₂O₇, _F d -3 m_); per-reflection F² against
   FullProf reference with anisotropic ADPs and empirical extinction.
   Cryspy extinction (`becker-coppens`, `gauss`) uses two parameters,
diff --git a/docs/docs/verification/sg-neut-cwl_ext-iso_tbti.ipynb b/docs/docs/verification/sc-neut-cwl_ext-iso_tbti.ipynb
similarity index 99%
rename from docs/docs/verification/sg-neut-cwl_ext-iso_tbti.ipynb
rename to docs/docs/verification/sc-neut-cwl_ext-iso_tbti.ipynb
index 413811c6a..3d486427a 100644
--- a/docs/docs/verification/sg-neut-cwl_ext-iso_tbti.ipynb
+++ b/docs/docs/verification/sc-neut-cwl_ext-iso_tbti.ipynb
@@ -161,7 +161,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "FULLPROF_PROJECT_DIR = 'sg-neut-cwl_ext-iso_tbti'\n",
+    "FULLPROF_PROJECT_DIR = 'sc-neut-cwl_ext-iso_tbti'\n",
     "FULLPROF_OUT_FILE = 'tbti.out'\n",
     "FULLPROF_SCALE = 0.37517014  # FullProf Scale\n",
     "FULLPROF_WAVELENGTH = 0.7930  # FullProf Lambda\n",
diff --git a/docs/docs/verification/sg-neut-cwl_ext-iso_tbti.py b/docs/docs/verification/sc-neut-cwl_ext-iso_tbti.py
similarity index 98%
rename from docs/docs/verification/sg-neut-cwl_ext-iso_tbti.py
rename to docs/docs/verification/sc-neut-cwl_ext-iso_tbti.py
index 6628b683c..68d359b5b 100644
--- a/docs/docs/verification/sg-neut-cwl_ext-iso_tbti.py
+++ b/docs/docs/verification/sc-neut-cwl_ext-iso_tbti.py
@@ -86,7 +86,7 @@
 # ## Load the FullProf reference
 
 # %%
-FULLPROF_PROJECT_DIR = 'sg-neut-cwl_ext-iso_tbti'
+FULLPROF_PROJECT_DIR = 'sc-neut-cwl_ext-iso_tbti'
 FULLPROF_OUT_FILE = 'tbti.out'
 FULLPROF_SCALE = 0.37517014  # FullProf Scale
 FULLPROF_WAVELENGTH = 0.7930  # FullProf Lambda
diff --git a/docs/docs/verification/sg-neut-cwl_noext_tbti.ipynb b/docs/docs/verification/sc-neut-cwl_noext_tbti.ipynb
similarity index 99%
rename from docs/docs/verification/sg-neut-cwl_noext_tbti.ipynb
rename to docs/docs/verification/sc-neut-cwl_noext_tbti.ipynb
index e44d2c79a..6dcd17ac6 100644
--- a/docs/docs/verification/sg-neut-cwl_noext_tbti.ipynb
+++ b/docs/docs/verification/sc-neut-cwl_noext_tbti.ipynb
@@ -161,7 +161,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "FULLPROF_PROJECT_DIR = 'sg-neut-cwl_noext_tbti'\n",
+    "FULLPROF_PROJECT_DIR = 'sc-neut-cwl_noext_tbti'\n",
     "FULLPROF_OUT_FILE = 'tbti.out'\n",
     "FULLPROF_SCALE = 0.28749475  # FullProf Scale\n",
     "FULLPROF_WAVELENGTH = 0.7930  # FullProf Lambda\n",
diff --git a/docs/docs/verification/sg-neut-cwl_noext_tbti.py b/docs/docs/verification/sc-neut-cwl_noext_tbti.py
similarity index 98%
rename from docs/docs/verification/sg-neut-cwl_noext_tbti.py
rename to docs/docs/verification/sc-neut-cwl_noext_tbti.py
index 803fbeb2f..da2aecd97 100644
--- a/docs/docs/verification/sg-neut-cwl_noext_tbti.py
+++ b/docs/docs/verification/sc-neut-cwl_noext_tbti.py
@@ -86,7 +86,7 @@
 # ## Load the FullProf reference
 
 # %%
-FULLPROF_PROJECT_DIR = 'sg-neut-cwl_noext_tbti'
+FULLPROF_PROJECT_DIR = 'sc-neut-cwl_noext_tbti'
 FULLPROF_OUT_FILE = 'tbti.out'
 FULLPROF_SCALE = 0.28749475  # FullProf Scale
 FULLPROF_WAVELENGTH = 0.7930  # FullProf Lambda
diff --git a/docs/docs/verification/sg-neut-cwl_pr2nio4.ipynb b/docs/docs/verification/sc-neut-cwl_pr2nio4.ipynb
similarity index 99%
rename from docs/docs/verification/sg-neut-cwl_pr2nio4.ipynb
rename to docs/docs/verification/sc-neut-cwl_pr2nio4.ipynb
index bfb620839..d92c5cd23 100644
--- a/docs/docs/verification/sg-neut-cwl_pr2nio4.ipynb
+++ b/docs/docs/verification/sc-neut-cwl_pr2nio4.ipynb
@@ -196,7 +196,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "FULLPROF_PROJECT_DIR = 'sg-neut-cwl_pr2nio4'\n",
+    "FULLPROF_PROJECT_DIR = 'sc-neut-cwl_pr2nio4'\n",
     "FULLPROF_OUT_FILE = 'prnio.out'\n",
     "FULLPROF_SCALE = 0.06298  # FullProf Scale\n",
     "FULLPROF_WAVELENGTH = 0.8302  # FullProf Lambda\n",
diff --git a/docs/docs/verification/sg-neut-cwl_pr2nio4.py b/docs/docs/verification/sc-neut-cwl_pr2nio4.py
similarity index 99%
rename from docs/docs/verification/sg-neut-cwl_pr2nio4.py
rename to docs/docs/verification/sc-neut-cwl_pr2nio4.py
index 5f6984856..faa916e40 100644
--- a/docs/docs/verification/sg-neut-cwl_pr2nio4.py
+++ b/docs/docs/verification/sc-neut-cwl_pr2nio4.py
@@ -121,7 +121,7 @@
 # ## Load the FullProf reference
 
 # %%
-FULLPROF_PROJECT_DIR = 'sg-neut-cwl_pr2nio4'
+FULLPROF_PROJECT_DIR = 'sc-neut-cwl_pr2nio4'
 FULLPROF_OUT_FILE = 'prnio.out'
 FULLPROF_SCALE = 0.06298  # FullProf Scale
 FULLPROF_WAVELENGTH = 0.8302  # FullProf Lambda
diff --git a/docs/mkdocs.yml b/docs/mkdocs.yml
index 29192b99d..b525f40c6 100644
--- a/docs/mkdocs.yml
+++ b/docs/mkdocs.yml
@@ -232,8 +232,8 @@ nav:
           - Si pd-neut-tof: tutorials/ed-28.ipynb
           - NaCl pd-xray: tutorials/ed-29.ipynb
       - Single Crystal Diffraction:
-          - Tb2TiO7 sg-neut-cwl: tutorials/ed-14.ipynb
-          - Taurine sg-neut-tof: tutorials/ed-15.ipynb
+          - Tb2TiO7 sc-neut-cwl: tutorials/ed-14.ipynb
+          - Taurine sc-neut-tof: tutorials/ed-15.ipynb
       - Pair Distribution Function:
           - Ni pd-neut-cwl: tutorials/ed-10.ipynb
           - Si pd-neut-tof: tutorials/ed-11.ipynb
@@ -267,9 +267,9 @@ nav:
           - Si (Jorgensen–Von Dreele): verification/pd-neut-tof_jvd_si.ipynb
           - NaCaAlF: verification/pd-neut-tof_jvd_ncaf.ipynb
       - Single crystal, neutron, constant wavelength:
-          - Pr2NiO4 (no extinction): verification/sg-neut-cwl_pr2nio4.ipynb
-          - Tb2Ti2O7 (no extinction): verification/sg-neut-cwl_noext_tbti.ipynb
-          - Tb2Ti2O7: verification/sg-neut-cwl_ext-iso_tbti.ipynb
+          - Pr2NiO4 (no extinction): verification/sc-neut-cwl_pr2nio4.ipynb
+          - Tb2Ti2O7 (no extinction): verification/sc-neut-cwl_noext_tbti.ipynb
+          - Tb2Ti2O7: verification/sc-neut-cwl_ext-iso_tbti.ipynb
   - Command-Line:
       - Command-Line: cli/index.md
   - API Reference:
diff --git a/src/easydiffraction/analysis/analysis.py b/src/easydiffraction/analysis/analysis.py
index 364d053b7..7b3dfc4ff 100644
--- a/src/easydiffraction/analysis/analysis.py
+++ b/src/easydiffraction/analysis/analysis.py
@@ -194,6 +194,16 @@ def _summary_parameters(
             if param._identity.category_code not in _SUMMARY_HIDDEN_PARAMETER_CATEGORIES
         ]
 
+    def _summary_parameters_by_datablock(
+        self,
+    ) -> dict[str, list[GenericDescriptorBase]]:
+        """Return summary parameters grouped by datablock kind."""
+        project = self._analysis.project
+        return {
+            'structures': self._summary_parameters(project.structures.parameters),
+            'experiments': self._summary_parameters(project.experiments.parameters),
+        }
+
     def all_params(self) -> None:
         """Print all parameters for structures and experiments."""
         project = self._analysis.project
@@ -307,14 +317,9 @@ def how_to_access_parameters(self) -> None:
         code.
         """
         project = self._analysis.project
-        structures_params = self._summary_parameters(project.structures.parameters)
-        experiments_params = self._summary_parameters(project.experiments.parameters)
-        all_params = {
-            'structures': structures_params,
-            'experiments': experiments_params,
-        }
+        all_params = self._summary_parameters_by_datablock()
 
-        if not structures_params and not experiments_params:
+        if not all_params['structures'] and not all_params['experiments']:
             log.warning('No parameters found.')
             return
 
@@ -370,15 +375,9 @@ def parameter_cif_uids(self) -> None:
         The output explains which unique identifiers are used when
         creating CIF-based constraints.
         """
-        project = self._analysis.project
-        structures_params = self._summary_parameters(project.structures.parameters)
-        experiments_params = self._summary_parameters(project.experiments.parameters)
-        all_params = {
-            'structures': structures_params,
-            'experiments': experiments_params,
-        }
+        all_params = self._summary_parameters_by_datablock()
 
-        if not structures_params and not experiments_params:
+        if not all_params['structures'] and not all_params['experiments']:
             log.warning('No parameters found.')
             return
 
diff --git a/src/easydiffraction/analysis/fit_helpers/bayesian.py b/src/easydiffraction/analysis/fit_helpers/bayesian.py
index 773d3dacc..1ee864946 100644
--- a/src/easydiffraction/analysis/fit_helpers/bayesian.py
+++ b/src/easydiffraction/analysis/fit_helpers/bayesian.py
@@ -28,7 +28,6 @@
 ESS_BULK_CONVERGENCE_THRESHOLD = 400.0
 POSTERIOR_SAMPLE_NDIM = 3
 DEFAULT_CI_LEVELS = (0.68, 0.95)
-DEFAULT_CREDIBLE_INTERVAL_LEVELS = DEFAULT_CI_LEVELS
 IntervalLevels = tuple[float, ...]
 SettingsMap = dict[str, object] | None
 DiagnosticsMap = dict[str, object] | None
diff --git a/src/easydiffraction/analysis/minimizers/base.py b/src/easydiffraction/analysis/minimizers/base.py
index fd2af7bad..c8a50b716 100644
--- a/src/easydiffraction/analysis/minimizers/base.py
+++ b/src/easydiffraction/analysis/minimizers/base.py
@@ -51,7 +51,6 @@ def __init__(
         self._max_iterations: int | None = max_iterations
         self.result: FitResults | None = None
         self._previous_chi2: float | None = None
-        self._iteration: int | None = None
         self._best_chi2: float | None = None
         self._best_iteration: int | None = None
         self._fitting_time: float | None = None
diff --git a/src/easydiffraction/analysis/minimizers/lmfit.py b/src/easydiffraction/analysis/minimizers/lmfit.py
index b564d3512..e3b7c5ed9 100644
--- a/src/easydiffraction/analysis/minimizers/lmfit.py
+++ b/src/easydiffraction/analysis/minimizers/lmfit.py
@@ -130,31 +130,3 @@ def _check_success(self, raw_result: object) -> bool:  # noqa: PLR6301
             True if the optimization was successful, False otherwise.
         """
         return getattr(raw_result, 'success', False)
-
-    def _iteration_callback(
-        self,
-        params: lmfit.Parameters,
-        iter: int,
-        resid: object,
-        *args: object,
-        **kwargs: object,
-    ) -> None:
-        """
-        Handle each iteration callback of the minimizer.
-
-        Parameters
-        ----------
-        params : lmfit.Parameters
-            The current parameters.
-        iter : int
-            The current iteration number.
-        resid : object
-            The residuals.
-        *args : object
-            Additional positional arguments.
-        **kwargs : object
-            Additional keyword arguments.
-        """
-        # Intentionally unused, required by callback signature
-        del params, resid, args, kwargs
-        self._iteration = iter
diff --git a/src/easydiffraction/core/guard.py b/src/easydiffraction/core/guard.py
index 51715bdc7..8226960a2 100644
--- a/src/easydiffraction/core/guard.py
+++ b/src/easydiffraction/core/guard.py
@@ -145,16 +145,6 @@ def _public_writable_attrs(cls) -> set[str]:
         """Public properties with a setter."""
         return {key for key, prop in cls._iter_properties() if prop.fset is not None}
 
-    def _allowed_attrs(
-        self,
-        *,
-        writable_only: bool = False,
-    ) -> set[str]:
-        cls = type(self)
-        if writable_only:
-            return cls._public_writable_attrs()
-        return cls._public_attrs()
-
     @property
     def _log_name(self) -> str:
         return self.unique_name or type(self).__name__
diff --git a/src/easydiffraction/display/plotting.py b/src/easydiffraction/display/plotting.py
index 0f99dfb93..1334dbd98 100644
--- a/src/easydiffraction/display/plotting.py
+++ b/src/easydiffraction/display/plotting.py
@@ -153,7 +153,6 @@ class PosteriorPairPlotStyleEnum(StrEnum):
 POSTERIOR_PAIR_AUTO_MAX_CONTOUR_PARAMETERS = 6
 PAIR_PLOT_CELL_SIZE_PIXELS = 190
 PAIR_PLOT_MIN_CELL_SIZE_PIXELS = 90
-PAIR_PLOT_MIN_SIZE_PIXELS = 680
 PAIR_PLOT_MARGIN_PIXELS = 120
 PAIR_PLOT_ESTIMATED_CONTAINER_WIDTH_PIXELS = 980
 PAIR_PLOT_SUBPLOT_SPACING = 0.01
@@ -164,7 +163,6 @@ class PosteriorPairPlotStyleEnum(StrEnum):
 POSTERIOR_PAIR_X_TITLE_YSHIFT_PIXELS = 10
 SQUARE_MATRIX_TITLE_YSHIFT_PIXELS = 12
 POSTERIOR_PAIR_GUIDE_LINE_COLOR = 'rgba(125, 140, 173, 0.18)'
-SQUARE_MATRIX_FIXED_ASPECT_RATIO = '1 / 1'
 SQUARE_MATRIX_FIXED_ASPECT_META_KEY = 'fixed_aspect_wrapper'
 SQUARE_MATRIX_LEFT_MARGIN_PIXELS = 40
 SQUARE_MATRIX_RIGHT_MARGIN_PIXELS = 24
@@ -2631,20 +2629,6 @@ def _posterior_pair_cell_size_pixels(
             )
         )
 
-    @classmethod
-    def _posterior_pair_figure_height_pixels(cls, n_parameters: int) -> int:
-        """
-        Return the initial figure height for a responsive pair plot.
-        """
-        cell_size = cls._posterior_pair_cell_size_pixels(
-            n_parameters,
-            available_width_pixels=PAIR_PLOT_ESTIMATED_CONTAINER_WIDTH_PIXELS,
-        )
-        return max(
-            PAIR_PLOT_MIN_SIZE_PIXELS,
-            cell_size * n_parameters + PAIR_PLOT_MARGIN_PIXELS,
-        )
-
     @staticmethod
     def _posterior_pair_contour_panel_count(n_parameters: int) -> int:
         """Return the number of lower-triangle contour panels."""
diff --git a/src/easydiffraction/project/categories/info/default.py b/src/easydiffraction/project/categories/info/default.py
index 61a85fdad..20aab0a88 100644
--- a/src/easydiffraction/project/categories/info/default.py
+++ b/src/easydiffraction/project/categories/info/default.py
@@ -153,13 +153,6 @@ def created(self) -> datetime.datetime:
         """Return the creation timestamp."""
         return self._parse_timestamp(self._created_descriptor.value)
 
-    def _set_created(self, value: datetime.datetime | str) -> None:
-        """Set the creation timestamp from runtime or CIF input."""
-        if isinstance(value, datetime.datetime):
-            self._created_descriptor.value = self._format_timestamp(value)
-            return
-        self._created_descriptor.value = value
-
     @property
     def last_modified(self) -> datetime.datetime:
         """Return the last modified timestamp."""