igerber · igerber · Apr 17, 2026 · Apr 16, 2026 · Apr 16, 2026 · Apr 16, 2026
diff --git a/.claude/commands/bump-version.md b/.claude/commands/bump-version.md
@@ -24,7 +24,7 @@ Files that need updating:
 | `pyproject.toml` | `version = "X.Y.Z"` | ~7 |
 | `rust/Cargo.toml` | `version = "X.Y.Z"` | ~3 |
 | `CHANGELOG.md` | Section header + comparison link | Top + bottom |
-| `docs/llms-full.txt` | `- Version: X.Y.Z` | ~5 |
+| `diff_diff/guides/llms-full.txt` | `- Version: X.Y.Z` | ~5 |
 
 ## Instructions
 
@@ -80,7 +80,7 @@ Files that need updating:
      Replace `version = "OLD_VERSION"` (the first version line under [package]) with `version = "NEW_VERSION"`
      Note: Rust version may differ from Python version; always sync to the new version
 
-   - `docs/llms-full.txt`:
+   - `diff_diff/guides/llms-full.txt`:
      Replace `- Version: OLD_VERSION` with `- Version: NEW_VERSION`
 
 6. **Update CHANGELOG comparison links**:
@@ -101,7 +101,7 @@ Files that need updating:
    - diff_diff/__init__.py: __version__ = "NEW_VERSION"
    - pyproject.toml: version = "NEW_VERSION"
    - rust/Cargo.toml: version = "NEW_VERSION"
-   - docs/llms-full.txt: Version: NEW_VERSION
+   - diff_diff/guides/llms-full.txt: Version: NEW_VERSION
    - CHANGELOG.md: Added/verified [NEW_VERSION] entry
 
    Next steps:

diff --git a/CLAUDE.md b/CLAUDE.md
@@ -139,7 +139,7 @@ category (`Methodology/Correctness`, `Performance`, or `Testing/Docs`):
 | `CONTRIBUTING.md` | Documentation requirements, test writing guidelines |
 | `.claude/commands/dev-checklists.md` | Checklists for params, methodology, warnings, reviews, bugs (run `/dev-checklists`) |
 | `.claude/memory.md` | Debugging patterns, tolerances, API conventions (git-tracked) |
-| `docs/llms-practitioner.txt` | Baker et al. (2025) 8-step practitioner workflow for AI agents |
+| `diff_diff/guides/llms-practitioner.txt` | Baker et al. (2025) 8-step practitioner workflow for AI agents (accessible at runtime via `diff_diff.get_llm_guide("practitioner")`) |
 | `docs/performance-plan.md` | Performance optimization details |
 | `docs/benchmarks.rst` | Validation results vs R |
 

diff --git a/README.md b/README.md
@@ -69,11 +69,19 @@ Signif. codes: '***' 0.001, '**' 0.01, '*' 0.05, '.' 0.1
 
 ## For AI Agents
 
-If you are an AI agent or LLM using this library, read [`docs/llms.txt`](docs/llms.txt) for a concise API reference with an 8-step practitioner workflow (based on Baker et al. 2025). The workflow ensures rigorous DiD analysis — not just calling `fit()`, but testing assumptions, running sensitivity analysis, and checking robustness.
+If you are an AI agent or LLM using this library, call `diff_diff.get_llm_guide()` for a concise API reference with an 8-step practitioner workflow (based on Baker et al. 2025). The workflow ensures rigorous DiD analysis — not just calling `fit()`, but testing assumptions, running sensitivity analysis, and checking robustness.
 
-After estimation, call `practitioner_next_steps(results)` for context-aware guidance on remaining diagnostic steps.
+```python
+from diff_diff import get_llm_guide
+
+get_llm_guide()                 # concise API reference
+get_llm_guide("practitioner")   # 8-step workflow (Baker et al. 2025)
+get_llm_guide("full")           # comprehensive documentation
+```
+
+The guides are bundled in the wheel, so they are accessible from a `pip install` with no network access required.
 
-Detailed guide: [`docs/llms-practitioner.txt`](docs/llms-practitioner.txt)
+After estimation, call `practitioner_next_steps(results)` for context-aware guidance on remaining diagnostic steps.
 
 ## For Data Scientists
 

diff --git a/diff_diff/__init__.py b/diff_diff/__init__.py
@@ -4,12 +4,14 @@
 This library provides sklearn-like estimators for causal inference
 using the difference-in-differences methodology.
 
-For rigorous analysis, follow the 8-step practitioner workflow in
-docs/llms-practitioner.txt (based on Baker et al. 2025). After
-estimation, call ``practitioner_next_steps(results)`` for context-aware
-guidance on remaining diagnostic steps.
+For rigorous analysis, follow the 8-step practitioner workflow based
+on Baker et al. (2025). After estimation, call
+``practitioner_next_steps(results)`` for context-aware guidance on
+remaining diagnostic steps.
 
-AI agent reference: docs/llms.txt
+AI agents: call ``diff_diff.get_llm_guide()`` for a complete API reference.
+Use ``get_llm_guide("practitioner")`` for the 8-step workflow or
+``get_llm_guide("full")`` for comprehensive documentation.
 """
 
 # Import backend detection from dedicated module (avoids circular imports)
@@ -200,6 +202,7 @@
     plot_synth_weights,
 )
 from diff_diff.practitioner import practitioner_next_steps
+from diff_diff._guides_api import get_llm_guide
 from diff_diff.datasets import (
     clear_cache,
     list_datasets,
@@ -402,4 +405,6 @@
     "clear_cache",
     # Practitioner guidance
     "practitioner_next_steps",
+    # LLM guide accessor
+    "get_llm_guide",
 ]
diff --git a/diff_diff/_guides_api.py b/diff_diff/_guides_api.py
@@ -0,0 +1,48 @@
+"""Runtime accessor for bundled LLM guide files."""
+from __future__ import annotations
+
+from importlib.resources import files
+
+_VARIANT_TO_FILE = {
+    "concise": "llms.txt",
+    "full": "llms-full.txt",
+    "practitioner": "llms-practitioner.txt",
+}
+
+
+def get_llm_guide(variant: str = "concise") -> str:
+    """Return the contents of a bundled LLM guide.
+
+    Parameters
+    ----------
+    variant : str, default "concise"
+        Which guide to load. Names are case-sensitive. One of:
+
+        - ``"concise"`` -- compact API reference (llms.txt)
+        - ``"full"`` -- complete API documentation (llms-full.txt)
+        - ``"practitioner"`` -- 8-step practitioner workflow (llms-practitioner.txt)
+
+    Returns
+    -------
+    str
+        The full text of the requested guide.
+
+    Raises
+    ------
+    ValueError
+        If ``variant`` is not one of the known guide names.
+
+    Examples
+    --------
+    >>> from diff_diff import get_llm_guide
+    >>> concise = get_llm_guide()
+    >>> workflow = get_llm_guide("practitioner")
+    """
+    try:
+        filename = _VARIANT_TO_FILE[variant]
+    except (KeyError, TypeError):
+        valid = ", ".join(repr(k) for k in _VARIANT_TO_FILE)
+        raise ValueError(
+            f"Unknown guide variant {variant!r}. Valid options: {valid}."
+        ) from None
+    return files("diff_diff.guides").joinpath(filename).read_text(encoding="utf-8")
diff --git a/diff_diff/guides/__init__.py b/diff_diff/guides/__init__.py
@@ -0,0 +1 @@
+"""LLM guide files bundled with diff-diff."""
diff --git a/docs/llms-full.txt → diff_diff/guides/llms-full.txt b/docs/llms-full.txt → diff_diff/guides/llms-full.txt
@@ -33,7 +33,7 @@ print(f"ATT: {results.att:.3f} (SE: {results.se:.3f})")
 
 ## Practitioner Workflow (based on Baker et al. 2025)
 
-For rigorous DiD analysis, follow the 8-step framework in docs/llms-practitioner.txt.
+For rigorous DiD analysis, follow the 8-step framework (call `diff_diff.get_llm_guide("practitioner")`).
 After estimation, call:
 
 ```python
@@ -1029,6 +1029,12 @@ Returned by `SyntheticDiD.fit()`.
 
 **Methods:** `summary()`, `print_summary()`, `to_dict()`, `to_dataframe()`, `get_unit_weights_df()`, `get_time_weights_df()`
 
+**Validation diagnostics** (call after `fit()`):
+- `get_weight_concentration(top_k=5)` - effective N and top-k weight share; flags fragile synthetic controls dominated by a few donor units
+- `get_loo_effects_df()` - per-unit leave-one-out influence from the jackknife pass (DataFrame includes both control and treated rows). Requires `variance_method="jackknife"`; raises `ValueError` if LOO is unavailable (see the method docstring for the full set of conditions, e.g. single treated unit or only one control with nonzero effective weight)
+- `in_time_placebo()` - re-estimate on shifted fake treatment dates in the pre-period; near-zero placebo ATTs indicate a credible design
+- `sensitivity_to_zeta_omega()` - re-estimate across a grid of unit-weight regularization values; checks ATT robustness to the auto-selected zeta_omega
+
 ### TripleDifferenceResults
 
 Returned by `TripleDifference.fit()`.

diff --git a/docs/llms-practitioner.txt → diff_diff/guides/llms-practitioner.txt b/docs/llms-practitioner.txt → diff_diff/guides/llms-practitioner.txt
@@ -3,7 +3,21 @@
 > An 8-step workflow for rigorous Difference-in-Differences analysis, based on
 > Baker et al. (2025) "Difference-in-Differences Designs: A Practitioner's
 > Guide" and adapted for the diff-diff library. Some steps are reorganized or
-> extended relative to the paper (see docs/methodology/REGISTRY.md for details).
+> extended relative to the paper:
+>
+> - **Numbering**: diff-diff uses 1-Define, 2-Assumptions, 3-Test PT,
+>   4-Choose estimator, 5-Estimate, 6-Sensitivity, 7-Heterogeneity,
+>   8-Robustness. The paper uses 1-Define, 2-Assumptions, 3-Estimation method,
+>   4-Uncertainty, 5-Estimate, 6-Sensitivity, 7-Heterogeneity, 8-Keep learning.
+> - **Parallel trends testing** is a separate Step 3 (the paper embeds it in
+>   Step 2), to ensure AI agents execute it as a distinct action.
+> - **Sources of uncertainty** (paper's Step 4) are folded into Step 5
+>   (Estimate) with an explicit cluster-count check directive: >= 50 clusters
+>   for asymptotic SEs, otherwise wild bootstrap. The 50-cluster threshold is
+>   a diff-diff convention.
+> - **Step 8** is "Robustness & Reporting" (compare estimators, report with
+>   and without covariates). The paper's Step 8 is "Keep learning." The
+>   mandatory with/without covariate comparison is a diff-diff convention.
 
 ## Instructions for AI Agents
 
@@ -282,7 +296,8 @@ to your estimator's API. Examples:
 - **StackedDiD**: vary `clean_control` definition
 - **EfficientDiD**: compare `control_group='never_treated'` vs `'last_cohort'`
 - **ImputationDiD/TwoStageDiD**: leave-one-cohort-out, cross-estimator comparison
-- **SyntheticDiD/TROP**: in-time or in-space placebo (fake treatment date, leave-one-unit-out)
+- **SyntheticDiD**: built-in diagnostics on the results object - `results.in_time_placebo()`, `results.get_loo_effects_df()` (requires `variance_method="jackknife"` at fit time), `results.sensitivity_to_zeta_omega()`, and `results.get_weight_concentration()`
+- **TROP**: in-time or in-space placebo (fake treatment date, leave-one-unit-out)
 
 ```python
 from diff_diff import run_all_placebo_tests

diff --git a/docs/llms.txt → diff_diff/guides/llms.txt b/docs/llms.txt → diff_diff/guides/llms.txt
@@ -27,13 +27,13 @@ diagnostic steps produces unreliable results.
 After estimation, call `practitioner_next_steps(results)` for context-aware
 guidance on remaining steps.
 
-Full practitioner guide: docs/llms-practitioner.txt
+Full practitioner guide: call `diff_diff.get_llm_guide("practitioner")`
 
 ## Documentation
 
 ### Getting Started
 
-- [Practitioner Guide](docs/llms-practitioner.txt): 8-step workflow for rigorous DiD analysis (Baker et al. 2025) — **start here**
+- **Practitioner Guide** (call `diff_diff.get_llm_guide("practitioner")`): 8-step workflow for rigorous DiD analysis (Baker et al. 2025) — **start here**
 - [Quickstart](https://diff-diff.readthedocs.io/en/stable/quickstart.html): Installation, basic 2x2 DiD — column-name and formula interfaces, covariates, fixed effects, cluster-robust SEs
 - [Choosing an Estimator](https://diff-diff.readthedocs.io/en/stable/choosing_estimator.html): Decision flowchart for selecting the right estimator for your research design
 - [Troubleshooting](https://diff-diff.readthedocs.io/en/stable/troubleshooting.html): Common issues and solutions

diff --git a/docs/conf.py b/docs/conf.py
@@ -33,7 +33,7 @@
 ]
 
 templates_path = ["_templates"]
-exclude_patterns = ["_build", "Thumbs.db", ".DS_Store", "llms.txt", "llms-full.txt"]
+exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
 
 # -- Options for autodoc -----------------------------------------------------
 autodoc_default_options = {
@@ -71,7 +71,11 @@
     "https://diff-diff.readthedocs.io/en/stable/",
 )
 html_baseurl = _canonical_url
-html_extra_path = ["llms.txt", "llms-full.txt"]
+html_extra_path = [
+    "../diff_diff/guides/llms.txt",
+    "../diff_diff/guides/llms-full.txt",
+    "../diff_diff/guides/llms-practitioner.txt",
+]
 sitemap_url_scheme = "{link}"
 
 html_theme_options = {