diff --git a/.agent-plan.md b/.agent-plan.md
index 235747f..9930697 100644
--- a/.agent-plan.md
+++ b/.agent-plan.md
@@ -148,6 +148,12 @@ Documentation + CI:
 - [x] `leadforge/render/snapshots.py` — added comment documenting the feature-label temporal mismatch when `label_window_days < horizon_days` (features aggregate over full horizon; label uses shorter window)
 - [x] 7 new tests: default-90 unchanged, shorter window fewer conversions, 1-day window zero conversions, late conversions excluded (with day-offset verification), conversion_timestamp still set outside window, event counts unchanged by window, bundle round-trip integration; total 788 passing
 
+### M15: README + CHANGELOG polish (PR #46)
+
+- [x] `README.md` — removed all "coming in vX.Y.Z" placeholders; added working CLI quickstart, Python API example, exposure modes table, difficulty profiles table, output bundle layout, key design principles
+- [x] `CHANGELOG.md` — created; covers v0.1.0 through post-v0.5.0 improvements; user-facing descriptions grouped by version
+- [x] `.agent-plan.md` — updated deferred items table
+
 ### Fix: direct conversion bypass for pre-SQL leads (PR #45, closes #44)
 
 - [x] `leadforge/simulation/engine.py` — added `_DIRECT_CONVERSION_STAGES` and `_DIRECT_CONVERSION_DISCOUNT` (0.01) constants; pre-SQL leads (`mql`, `sal`) now have a small daily probability of converting directly, bypassing the full funnel
@@ -207,7 +213,7 @@ Documentation + CI:
 | M14: Notebook 2 (lead scoring baseline) | Deferred | v4 validation script covers this |
 | M14: Notebook 3 (public vs instructor) | Discarded | No current audience |
 | M14: Notebook 4 (recipe customization) | Discarded | Premature |
-| M15: Docs polish + v1.0 RC | Deferred | Do after v4 ships |
+| M15: Docs polish + v1.0 RC | **In progress** | README + CHANGELOG done; architecture diagram and notebooks remain |
 
 ### From post-v1 list
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..ac9ae7c
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,54 @@
+# Changelog
+
+All notable changes to leadforge are documented here.
+Format inspired by [Keep a Changelog](https://keepachangelog.com/).
+
+---
+
+## Unreleased
+
+- **Direct conversion bypass** (PR #45): pre-SQL leads can now convert via a rare direct path, fixing the deterministic `is_sql → converts` invariant.
+- **Configurable label window** (PR #43): `label_window_days` controls conversion label derivation in the simulation.
+- **Generalized task support** (PR #40, #42): `primary_task` threaded through bundle, validation, and pipelines; dataset card prose adapts to non-conversion tasks.
+- **Pipeline extraction** (PR #29, #34): build pipeline functions extracted into `leadforge.pipelines` with proper RNG conventions.
+- **Latent-aware touch intensity** (PR #31): `LatentDecayIntensity` mechanism creates causal link between latent traits and touch patterns.
+- **Canonical validation module** (PR #26): reusable lead scoring validation with sklearn pipeline.
+- **v4–v6 dataset pipelines**: progressive dataset versions with leakage traps, student/instructor splits, value-aware scoring, and GBM improvement validation.
+
+---
+
+## Milestone 0.5.0 — Validation Harness & CLI Complete (2026-04-29)
+
+- Full validation harness: determinism checks, exposure monotonicity, realism bounds, difficulty validation, cross-seed drift detection.
+- `leadforge validate` command with artifact checks, FK integrity, leakage detection, and task split validation.
+- Parquet metadata used for row counts (no full table reads during validation).
+
+## Milestone 0.4.0 — Simulation Engine & End-to-End Generation (2026-04-28)
+
+- 90-day daily-step simulation engine with churn, stage advancement, conversion hazards, and touch emission.
+- Population generation: accounts (3 latent traits), contacts (4 traits), leads (1 trait) with motif-family biases.
+- Full render pipeline: 9-table relational output, leakage-free lead snapshots, deterministic train/valid/test splits.
+- Exposure filtering: `student_public` and `research_instructor` modes with truth redaction.
+- CLI commands: `generate`, `inspect`, `validate`, `list-recipes` — all fully wired.
+- Bundle manifest with provenance, row counts, and SHA-256 file hashes.
+
+## Milestone 0.3.0 — World Structure & Mechanisms (2026-04-25)
+
+- Hidden world graph (DAG) with 5 motif families: fit-dominant, intent-dominant, sales-execution-sensitive, demo/trial-mediated, buying-committee-friction.
+- Stochastic graph rewiring: optional-node dropping, edge-weight jitter, latent-confounder injection.
+- Mechanism layer: latent scores, conversion hazards, stage transitions, Poisson intensities, categorical influences, noisy proxies.
+- Motif-aware mechanism assignment policies.
+
+## Milestone 0.2.0 — Config, Recipes & Narrative (2026-04-20)
+
+- Typed `GenerationConfig`, `Recipe`, `WorldSpec` models with full precedence resolution (kwargs > override > recipe > defaults).
+- Seeded RNG with SHA-256-derived named substreams for reproducibility.
+- Narrative layer: company, product, market, GTM motion, personas, funnel stages — loaded from recipe YAML.
+- Schema layer: 9 entity dataclasses, 10 FK constraints, 29 snapshot features, feature dictionary writer.
+- Dataset card renderer from narrative + world spec.
+
+## Milestone 0.1.0 — Project Foundation (2026-04-18)
+
+- Package skeleton, CLI entry point (`leadforge list-recipes`), CI pipeline.
+- Recipe registry with `b2b_saas_procurement_v1` recipe.
+- GitHub Actions: lint, typecheck, test matrix (Python 3.11 + 3.12).
diff --git a/README.md b/README.md
index 8582db3..5d7a2e9 100644
--- a/README.md
+++ b/README.md
@@ -2,16 +2,20 @@
 
 **Opinionated framework for generating synthetic CRM and GTM datasets from simulated commercial worlds.**
 
-`leadforge` generates narrative-grounded synthetic revenue datasets starting with lead scoring, designed to support teaching, portfolio projects, and research. Rather than sampling rows from a distribution, it simulates a commercial world — a specific company, selling a specific product, to a specific kind of buyer — and renders realistic CRM-style outputs from that world.
+`leadforge` generates narrative-grounded synthetic revenue datasets — starting with lead scoring — designed for teaching, portfolio projects, and research. Rather than sampling rows from a distribution, it simulates a commercial world: a specific company, selling a specific product, to a specific kind of buyer, and renders realistic CRM-style outputs from that world.
 
 ---
 
 ## Installation
 
+Requires **Python 3.11+**.
+
 ```bash
-pip install leadforge
+pip install git+https://github.com/leadforge-dev/leadforge.git
 ```
 
+> PyPI package coming with the v1.0 release.
+
 For development:
 
 ```bash
@@ -25,27 +29,29 @@ pre-commit install
 
 ## Quickstart
 
+### CLI
+
 ```bash
 # List available recipes
 leadforge list-recipes
 
-# Coming in v0.2.0: generate a dataset bundle
-# leadforge generate \
-#   --recipe b2b_saas_procurement_v1 \
-#   --seed 42 \
-#   --mode student_public \
-#   --difficulty intermediate \
-#   --n-leads 5000 \
-#   --out ./out/demo_bundle
+# Generate a dataset bundle
+leadforge generate \
+  --recipe b2b_saas_procurement_v1 \
+  --seed 42 \
+  --mode student_public \
+  --difficulty intermediate \
+  --n-leads 5000 \
+  --out ./out/demo_bundle
 
-# Coming in v0.4.0: inspect a generated bundle
-# leadforge inspect ./out/demo_bundle
+# Inspect bundle metadata
+leadforge inspect ./out/demo_bundle
 
-# Coming in v0.5.0: validate a generated bundle
-# leadforge validate ./out/demo_bundle
+# Validate bundle integrity
+leadforge validate ./out/demo_bundle
 ```
 
-**Python API** (coming in v0.2.0):
+### Python API
 
 ```python
 from leadforge.api import Generator
@@ -61,11 +67,82 @@ bundle.save("./out/demo_bundle")
 
 ---
 
+## Exposure Modes
+
+Control what truth is visible in the output bundle:
+
+| Mode | Purpose | Includes |
+|------|---------|----------|
+| `student_public` | Teaching / portfolio use | Tables, features, task splits, dataset card |
+| `research_instructor` | Full truth for instructors / researchers | All of the above + hidden graph, world spec, latent registry, mechanism summary |
+
+Set via `--mode` on the CLI or `exposure_mode=` in the Python API.
+
+---
+
+## Difficulty Profiles
+
+Each recipe ships with difficulty profiles that control signal-to-noise ratio:
+
+| Profile | Description |
+|---------|-------------|
+| `intro` | Strong signal, low noise — good for first-time learners |
+| `intermediate` | Moderate signal, realistic noise |
+| `advanced` | Weak signal, high noise — challenges experienced practitioners |
+
+Set via `--difficulty` on the CLI or `difficulty=` in `generate()`.
+
+---
+
+## Output Bundle
+
+```
+bundle_root/
+  manifest.json            # provenance, row counts, file hashes
+  dataset_card.md          # human-readable dataset documentation
+  feature_dictionary.csv   # feature names, types, descriptions
+  tables/                  # 9 relational Parquet tables
+  tasks/
+    converted_within_90_days/
+      train.parquet
+      valid.parquet
+      test.parquet
+      task_manifest.json
+  metadata/                # (research_instructor only) hidden graph, world spec, latents
+```
+
+---
+
+## Key Design Principles
+
+- **Deterministic**: same (recipe, seed, version) → identical output.
+- **Relational-first**: 9 normalized tables; flat ML exports are derived.
+- **No external APIs**: core generation never requires network access.
+- **Simulation-driven labels**: `converted_within_90_days` emerges from simulated events, not sampled directly.
+- **Leakage-safe**: no feature uses events after the snapshot anchor.
+
+---
+
 ## Documentation
 
 - [Design document](docs/leadforge_design_doc.md)
 - [Architecture spec](docs/leadforge_architecture_spec.md)
 - [Implementation plan](docs/leadforge_implementation_plan.md)
+- [v4 dataset design](docs/v4/design.md)
+- [Changelog](CHANGELOG.md)
+
+---
+
+## Development
+
+```bash
+pip install -e ".[dev]"
+pytest                        # run all tests (~800)
+ruff check .                  # lint
+ruff format .                 # format
+mypy leadforge/               # type check
+pre-commit run --all-files    # full pre-commit suite
+```
 
 ---