diff --git a/vcs/types.go b/vcs/types.go
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+// Package vcs defines shared types used across VCS client implementations
+// (gitea, github). Keeping them here prevents the client packages from
+// importing each other or duplicating definitions.
+package vcs
+
+// ReviewEvent is the verdict submitted with a pull request review.
+type ReviewEvent string
+
+const (
+	// ReviewEventApprove approves the pull request.
+	ReviewEventApprove ReviewEvent = "APPROVE"
+
+	// ReviewEventRequestChanges requests changes before the PR can be merged.
+	ReviewEventRequestChanges ReviewEvent = "REQUEST_CHANGES"
+
+	// ReviewEventComment leaves a comment review without explicit approval or rejection.
+	ReviewEventComment ReviewEvent = "COMMENT"
+)
+
+// UserInfo holds the identity of a user.
+type UserInfo struct {
+	Login string
+}
+
+// ReviewComment is a single inline comment attached to a pull request review.
+type ReviewComment struct {
+	// Path is the file path the comment applies to.
+	Path string
+
+	// Position is the line position within the diff (1-indexed).
+	// GitHub and Gitea differ in how they compute position; callers must
+	// supply the correct value for the target VCS.
+	Position int
+
+	// Body is the text content of the comment.
+	Body string
+
+	// CommitID is the SHA of the commit the comment applies to.
+	// For GitHub, all comments within a single review must target the same commit.
+	CommitID string
+}
+
+// ReviewRequest is the payload for submitting a pull request review.
+type ReviewRequest struct {
+	// Body is the top-level review comment body.
+	Body string
+
+	// Event is the review verdict.
+	Event ReviewEvent
+
+	// Comments are optional inline file-level comments.
+	Comments []ReviewComment
+}
+
+// Review represents a submitted pull request review.
+type Review struct {
+	// ID is the provider-assigned review identifier.
+	ID int64
+
+	// Body is the top-level review comment body.
+	Body string
+
+	// User is the author of the review.
+	User UserInfo
+
+	// State is the canonical review state string.
+	// Values: APPROVE, REQUEST_CHANGES, COMMENT, DISMISSED, PENDING.
+	State string
+
+	// CommitID is the commit SHA the review was evaluated against.
+	CommitID string
+}