From e18ed7ef1199905c52acdfda92c741d33eee8c28 Mon Sep 17 00:00:00 2001
From: hidetzu <hidetzu@gmail.com>
Date: Sat, 11 Apr 2026 15:09:40 +0900
Subject: [PATCH] Add CHANGELOG.md (Keep a Changelog format)

Document the history of v0.1.0 through v0.3.0, with explicit Breaking
section for v0.3.0 covering the CLI JSON schema changes and migration
guidance link to docs/json-schema.md.

Link CHANGELOG.md from the README Releases section.
---
 CHANGELOG.md | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 README.md    |  2 ++
 2 files changed, 69 insertions(+)
 create mode 100644 CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..200dc4d
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,67 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [v0.3.0] - 2026-04-11
+
+### Added
+- Public library API at `pkg/prism` (`Analyze`, `Prompt`, sentinel errors)
+- `pkg/prism` happy-path integration tests with mock GitHub server
+- Test seam: `provider.NewRegistryWithGitHubBaseURL` for redirecting the GitHub provider to a local httptest server
+- Foundation for `prism-api` (HTTP service, separate repository)
+- ADR-0002: Public API Boundary
+
+### Changed
+- CLI `analyze` command now uses `pkg/prism.Analyze()` internally
+- CLI JSON output is now byte-identical to `pkg/prism.Result` (verified by golden test)
+- `internal/formatter` rewritten to take `prism.Result` as input
+- CLI exit-code mapping recognizes `pkg/prism` sentinel errors (`ErrInvalidInput`, `ErrUnsupportedProvider`, `ErrAuthRequired`, `ErrUpstreamFailure`)
+- README, `docs/architecture.md`, `docs/json-schema.md` updated to reflect the unified pipeline
+
+### Removed
+- `internal/usecase/analyze.go` (replaced by `pkg/prism.Analyze` + `internal/formatter`)
+- `internal/formatter/types.go` (formatter now uses `prism.Result` directly)
+
+### Breaking
+CLI JSON output structure changed to align with `pkg/prism.Result`:
+
+- `provider` moved from top-level to `pull_request.provider`
+- `pull_request.description` removed (use `prism fetch` for raw description)
+- `pull_request.url` added (canonical PR URL)
+- `changed_files[].patch` no longer included by default (library has `IncludePatches` opt-in)
+- Empty/zero fields are now omitted (`omitempty` semantics)
+
+These changes were made early in the project lifecycle. Impact is expected to be minimal. See [docs/json-schema.md](docs/json-schema.md#breaking-changes-in-v030) for the field-by-field migration guide.
+
+`prism prompt` and `prism fetch` commands are unchanged in this release; they still go through `internal/usecase` pending future extension of `pkg/prism.Prompt`.
+
+## [v0.2.0] - 2026-04-11
+
+### Added
+- Provider plugin architecture: external `prism-provider-<name>` binaries discovered on PATH
+- `--provider` flag for explicit provider selection (auto-detected from URL if omitted)
+- Provider plugin protocol v1 (versioned JSON contract for plugin authors)
+- AWS CodeCommit support via [prism-provider-codecommit](https://github.com/hidetzu/prism-provider-codecommit) plugin
+- ADR-0001: Provider Plugin Architecture
+- HTTP request timeout (30s) and pagination upper bound on the GitHub provider
+
+## [v0.1.0] - 2026-04-11
+
+### Added
+- Initial release: GitHub provider, `analyze`/`prompt`/`fetch` commands
+- Output formats: JSON, Markdown, text
+- Prompt modes: light, detailed, cross
+- Language support: English, Japanese
+- Custom template support (`--template`)
+- Configuration file (`~/.config/prism/config.yaml`)
+- Exit codes 0–4 for CI/CD integration
+
+[Unreleased]: https://github.com/hidetzu/prism/compare/v0.3.0...HEAD
+[v0.3.0]: https://github.com/hidetzu/prism/releases/tag/v0.3.0
+[v0.2.0]: https://github.com/hidetzu/prism/releases/tag/v0.2.0
+[v0.1.0]: https://github.com/hidetzu/prism/releases/tag/v0.1.0
diff --git a/README.md b/README.md
index f0a0723..50c086b 100644
--- a/README.md
+++ b/README.md
@@ -442,6 +442,8 @@ make clean    # Remove bin/
 - [v0.2.0](https://github.com/hidetzu/prism/releases/tag/v0.2.0) — Provider plugin architecture + CodeCommit support
 - [v0.1.0](https://github.com/hidetzu/prism/releases/tag/v0.1.0) — Initial release
 
+See [CHANGELOG.md](CHANGELOG.md) for the full history and breaking changes.
+
 ## License
 
 MIT