feat: add changelog command

README.md

@@ -216,7 +216,7 @@ Releases are automated via GoReleaser. Pushing a version tag triggers GitHub Act
 
 ```bash
 # Draft a changelog entry from the latest tag through HEAD
-td release-notes --version v0.2.0
+td changelog --version v0.2.0
 
 # Create and push an annotated tag (triggers automated release)
 make release VERSION=v0.2.0
@@ -422,7 +422,7 @@ Analytics are stored locally and help identify workflow patterns. Disable with `
 | Reject                           | `td reject <id> --reason "..."`                  |
 | Link files                       | `td link <id> <files...>`                        |
 | Check file changes               | `td files <id>`                                  |
-| Draft release notes              | `td release-notes --version v0.2.0`              |
+| Draft changelog entry            | `td changelog --version v0.2.0`                  |
 | Undo last action                 | `td undo`                                        |
 | New named session                | `td session --new "feature-work"`                |
 | Live dashboard                   | `td monitor`                                     |

cmd/changelog.go

@@ -0,0 +1,88 @@
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strings"
+	"time"
+
+	changelogpkg "github.com/marcus/td/internal/changelog"
+	gitutil "github.com/marcus/td/internal/git"
+	"github.com/spf13/cobra"
+)
+
+var (
+	changelogNow          = time.Now
+	releaseVersionPattern = regexp.MustCompile(`^v\d+\.\d+\.\d+(?:-[0-9A-Za-z.-]+)?(?:\+[0-9A-Za-z.-]+)?$`)
+)
+
+var changelogCmd = &cobra.Command{
+	Use:     "changelog",
+	Short:   "Draft a CHANGELOG.md entry from committed git history",
+	GroupID: "system",
+	Args:    cobra.NoArgs,
+	Long: `Draft a paste-ready CHANGELOG.md entry from committed git history.
+
+By default, td uses the latest reachable semver tag through HEAD as the
+baseline, filters out documentation/test/CI/chore commits, and prints a
+markdown block you can review before updating CHANGELOG.md manually.`,
+	Example: `  td changelog --version v0.44.0
+  td changelog --version v0.44.0 --date 2026-04-15
+  td changelog --version v0.44.0 --from v0.43.0 --to HEAD
+  td changelog --version v0.44.0 --to v0.44.0 --include-meta`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		fromRef, _ := cmd.Flags().GetString("from")
+		toRef, _ := cmd.Flags().GetString("to")
+		versionLabel, _ := cmd.Flags().GetString("version")
+		dateValue, _ := cmd.Flags().GetString("date")
+		includeMeta, _ := cmd.Flags().GetBool("include-meta")
+
+		versionLabel = strings.TrimSpace(versionLabel)
+		if versionLabel == "" {
+			return errors.New("--version is required")
+		}
+		if !releaseVersionPattern.MatchString(versionLabel) {
+			return fmt.Errorf("invalid --version %q: expected semver like v1.2.3", versionLabel)
+		}
+
+		releaseDate := changelogNow()
+		if strings.TrimSpace(dateValue) != "" {
+			parsedDate, err := time.Parse("2006-01-02", dateValue)
+			if err != nil {
+				return fmt.Errorf("invalid --date %q: expected YYYY-MM-DD", dateValue)
+			}
+			releaseDate = parsedDate
+		}
+
+		draft, err := changelogpkg.Generate(gitHistoryRepoDir(), changelogpkg.Options{
+			FromRef:     fromRef,
+			ToRef:       toRef,
+			Version:     versionLabel,
+			Date:        releaseDate,
+			IncludeMeta: includeMeta,
+		})
+		if err != nil {
+			switch {
+			case errors.Is(err, gitutil.ErrNotRepository):
+				return fmt.Errorf("changelog requires a git repository")
+			case errors.Is(err, gitutil.ErrNoSemverTag):
+				return fmt.Errorf("no reachable semver tag found; use --from to set the starting ref")
+			default:
+				return err
+			}
+		}
+
+		_, err = fmt.Fprint(cmd.OutOrStdout(), draft.Markdown())
+		return err
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(changelogCmd)
+	changelogCmd.Flags().String("from", "", "Start the range at this git ref or tag")
+	changelogCmd.Flags().String("to", "HEAD", "End the range at this git ref")
+	changelogCmd.Flags().String("version", "", "Version label for the markdown header (required)")
+	changelogCmd.Flags().String("date", "", "Release date for the markdown header (YYYY-MM-DD, default: today)")
+	changelogCmd.Flags().Bool("include-meta", false, "Include documentation, test, CI, and chore commits")
+}