fix(sanitize): preserve visible Markdown content

go.mod

@@ -19,6 +19,7 @@ require (
 	github.com/spf13/viper v1.21.0
 	github.com/stretchr/testify v1.12.1
 	github.com/yosida95/uritemplate/v3 v3.0.2
+	github.com/yuin/goldmark v1.8.5
 	golang.org/x/net v0.55.0
 	golang.org/x/oauth2 v0.36.0
 )

go.sum

@@ -75,6 +75,8 @@ github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSW
 github.com/yosida95/uritemplate/v3 v3.0.2 h1:Ed3Oyj9yrmi9087+NczuL5BwkIc4wvTb5zIM+UJPGz4=
 github.com/yosida95/uritemplate/v3 v3.0.2/go.mod h1:ILOh0sOhIJR3+L/8afwt/kE++YT040gmv5BQTMR2HP4=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+github.com/yuin/goldmark v1.8.5 h1:r6N5afV5qj/5S4UTch8agZHJ8UxNCMwX7WjkkJam2NA=
+github.com/yuin/goldmark v1.8.5/go.mod h1:ip/1k0VRfGynBgxOz0yCqHrbZXhcjxyuS66Brc7iBKg=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
 go.yaml.in/yaml/v3 v3.0.5 h1:N6y/pJk8buWs9NY5ERU2HSMfm+IuD/OtfdAnq6kESPw=
 go.yaml.in/yaml/v3 v3.0.5/go.mod h1:HVTZu1O7/Vkt2N+BFy8Zza+lnLsABggaTM2ZpNIGuKg=

pkg/github/discussions.go

@@ -362,7 +362,7 @@ func GetDiscussion(t translations.TranslationHelperFunc) inventory.ServerTool {
 			response := map[string]any{
 				"number":     int(d.Number),
 				"title":      sanitize.Sanitize(string(d.Title)),
-				"body":       sanitize.Sanitize(string(d.Body)),
+				"body":       sanitize.Content(string(d.Body)),
 				"url":        string(d.URL),
 				"closed":     bool(d.Closed),
 				"isAnswered": bool(d.IsAnswered),

pkg/github/discussions_test.go

@@ -571,7 +571,7 @@ func Test_GetDiscussion(t *testing.T) {
 			expected: map[string]any{
 				"number":     float64(1),
 				"title":      sanitizedText,
-				"body":       sanitizedText,
+				"body":       sanitizedContentText,
 				"url":        "https://github.com/owner/repo/discussions/1",
 				"closed":     false,
 				"isAnswered": false,

pkg/github/issues.go

@@ -1118,6 +1118,9 @@ func GetSubIssues(ctx context.Context, client *github.Client, deps ToolDependenc
 		subIssues = filteredSubIssues
 	}
 
+	for _, subIssue := range subIssues {
+		sanitizeSubIssueTitleAndBody(subIssue)
+	}
 	r, err := json.Marshal(subIssues)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -1708,6 +1711,7 @@ func AddSubIssue(ctx context.Context, client *github.Client, owner string, repo
 		return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to add sub-issue", resp, body), nil
 	}
 
+	sanitizeSubIssueTitleAndBody(subIssue)
 	r, err := json.Marshal(subIssue)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -1739,6 +1743,7 @@ func RemoveSubIssue(ctx context.Context, client *github.Client, owner string, re
 		return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to remove sub-issue", resp, body), nil
 	}
 
+	sanitizeSubIssueTitleAndBody(subIssue)
 	r, err := json.Marshal(subIssue)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -1788,6 +1793,7 @@ func ReprioritizeSubIssue(ctx context.Context, client *github.Client, owner stri
 		return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to reprioritize sub-issue", resp, body), nil
 	}
 
+	sanitizeSubIssueTitleAndBody(subIssue)
 	r, err := json.Marshal(subIssue)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -1998,7 +2004,19 @@ func sanitizeIssueTitleAndBody(issue *github.Issue) {
 		issue.Title = github.Ptr(sanitize.Sanitize(*issue.Title))
 	}
 	if issue.Body != nil {
-		issue.Body = github.Ptr(sanitize.Sanitize(*issue.Body))
+		issue.Body = github.Ptr(sanitize.Content(*issue.Body))
+	}
+}
+
+func sanitizeSubIssueTitleAndBody(issue *github.SubIssue) {
+	if issue == nil {
+		return
+	}
+	if issue.Title != nil {
+		issue.Title = github.Ptr(sanitize.Sanitize(*issue.Title))
+	}
+	if issue.Body != nil {
+		issue.Body = github.Ptr(sanitize.Content(*issue.Body))
 	}
 }
 

pkg/github/issues_test.go

@@ -6028,6 +6028,26 @@ func Test_GetSubIssues(t *testing.T) {
 			},
 		},
 	}
+	unsafeSubIssues := []*github.Issue{
+		{
+			Number:  github.Ptr(125),
+			Title:   github.Ptr(maliciousText),
+			Body:    github.Ptr(maliciousText),
+			State:   github.Ptr("open"),
+			HTMLURL: github.Ptr("https://github.com/owner/repo/issues/125"),
+			User:    &github.User{Login: github.Ptr("user3")},
+		},
+	}
+	sanitizedSubIssues := []*github.Issue{
+		{
+			Number:  github.Ptr(125),
+			Title:   github.Ptr(sanitizedText),
+			Body:    github.Ptr(sanitizedContentText),
+			State:   github.Ptr("open"),
+			HTMLURL: github.Ptr("https://github.com/owner/repo/issues/125"),
+			User:    &github.User{Login: github.Ptr("user3")},
+		},
+	}
 
 	tests := []struct {
 		name              string
@@ -6072,6 +6092,19 @@ func Test_GetSubIssues(t *testing.T) {
 			expectError:       false,
 			expectedSubIssues: mockSubIssues,
 		},
+		{
+			name: "sanitizes sub-issue titles and bodies",
+			mockedClient: MockHTTPClientWithHandlers(map[string]http.HandlerFunc{
+				GetReposIssuesSubIssuesByOwnerByRepoByIssueNumber: mockResponse(t, http.StatusOK, unsafeSubIssues),
+			}),
+			requestArgs: map[string]any{
+				"method":       "get_sub_issues",
+				"owner":        "owner",
+				"repo":         "repo",
+				"issue_number": float64(42),
+			},
+			expectedSubIssues: sanitizedSubIssues,
+		},
 		{
 			name: "successful sub-issues listing with empty result",
 			mockedClient: MockHTTPClientWithHandlers(map[string]http.HandlerFunc{

pkg/github/minimal_types.go

@@ -204,7 +204,7 @@ type MinimalDiscussionComment struct {
 func newMinimalDiscussionComment(id string, body string, isAnswer bool) MinimalDiscussionComment {
 	return MinimalDiscussionComment{
 		ID:       id,
-		Body:     sanitize.Sanitize(body),
+		Body:     sanitize.Content(body),
 		IsAnswer: isAnswer,
 	}
 }
@@ -797,7 +797,7 @@ func convertToMinimalPullRequestReview(review *github.PullRequestReview) Minimal
 	m := MinimalPullRequestReview{
 		ID:                review.GetID(),
 		State:             review.GetState(),
-		Body:              sanitize.Sanitize(review.GetBody()),
+		Body:              sanitize.Content(review.GetBody()),
 		HTMLURL:           review.GetHTMLURL(),
 		User:              convertToMinimalUser(review.GetUser()),
 		CommitID:          review.GetCommitID(),
@@ -815,7 +815,7 @@ func convertToMinimalIssue(issue *github.Issue) MinimalIssue {
 	m := MinimalIssue{
 		Number:            issue.GetNumber(),
 		Title:             sanitize.Sanitize(issue.GetTitle()),
-		Body:              sanitize.Sanitize(issue.GetBody()),
+		Body:              sanitize.Content(issue.GetBody()),
 		State:             issue.GetState(),
 		StateReason:       issue.GetStateReason(),
 		Draft:             issue.GetDraft(),
@@ -926,7 +926,7 @@ func fragmentWithoutFieldValuesToMinimalIssue(fragment issueFragmentWithoutField
 	m := MinimalIssue{
 		Number:    int(fragment.Number),
 		Title:     sanitize.Sanitize(string(fragment.Title)),
-		Body:      sanitize.Sanitize(string(fragment.Body)),
+		Body:      sanitize.Content(string(fragment.Body)),
 		State:     string(fragment.State),
 		Comments:  int(fragment.Comments.TotalCount),
 		CreatedAt: fragment.CreatedAt.Format(time.RFC3339),
@@ -1015,7 +1015,7 @@ func convertToMinimalIssuesResponseWithoutFieldValues(fragment issueQueryFragmen
 func convertToMinimalIssueComment(comment *github.IssueComment) MinimalIssueComment {
 	m := MinimalIssueComment{
 		ID:                comment.GetID(),
-		Body:              sanitize.Sanitize(comment.GetBody()),
+		Body:              sanitize.Content(comment.GetBody()),
 		HTMLURL:           comment.GetHTMLURL(),
 		User:              convertToMinimalUser(comment.GetUser()),
 		AuthorAssociation: comment.GetAuthorAssociation(),
@@ -1064,7 +1064,7 @@ func convertToMinimalFileContentResponse(resp *github.RepositoryContentResponse)
 
 	m.Commit = &MinimalFileCommit{
 		SHA:     resp.Commit.GetSHA(),
-		Message: sanitize.Sanitize(resp.Commit.GetMessage()),
+		Message: sanitize.Content(resp.Commit.GetMessage()),
 		HTMLURL: resp.Commit.GetHTMLURL(),
 	}
 
@@ -1085,7 +1085,7 @@ func convertToMinimalPullRequest(pr *github.PullRequest) MinimalPullRequest {
 	m := MinimalPullRequest{
 		Number:         pr.GetNumber(),
 		Title:          sanitize.Sanitize(pr.GetTitle()),
-		Body:           sanitize.Sanitize(pr.GetBody()),
+		Body:           sanitize.Content(pr.GetBody()),
 		State:          pr.GetState(),
 		Draft:          pr.GetDraft(),
 		Merged:         pr.GetMerged(),
@@ -1794,7 +1794,7 @@ func newMinimalCommitFromCore(sha, htmlURL string, commit *github.Commit, author
 
 	if commit != nil {
 		minimalCommit.Commit = &MinimalCommitInfo{
-			Message: sanitize.Sanitize(commit.GetMessage()),
+			Message: sanitize.Content(commit.GetMessage()),
 		}
 
 		if commit.Author != nil {
@@ -2000,7 +2000,7 @@ func convertToMinimalPullRequestCommits(commits []*github.RepositoryCommit) []Mi
 		}
 
 		if commit.Commit != nil {
-			minimalCommit.Message = sanitize.Sanitize(commit.Commit.GetMessage())
+			minimalCommit.Message = sanitize.Content(commit.Commit.GetMessage())
 			minimalCommit.Author = convertToMinimalCommitAuthor(commit.Commit.Author)
 		}
 
@@ -2039,7 +2039,7 @@ func convertToMinimalRelease(release *github.RepositoryRelease) MinimalRelease {
 		ID:         release.GetID(),
 		TagName:    release.GetTagName(),
 		Name:       sanitize.Sanitize(release.GetName()),
-		Body:       sanitize.Sanitize(release.GetBody()),
+		Body:       sanitize.Content(release.GetBody()),
 		HTMLURL:    release.GetHTMLURL(),
 		Prerelease: release.GetPrerelease(),
 		Draft:      release.GetDraft(),
@@ -2095,7 +2095,7 @@ func convertToMinimalWorkflowRun(workflowRun *github.WorkflowRun) MinimalWorkflo
 
 	if headCommit := workflowRun.GetHeadCommit(); headCommit != nil && headCommit.GetMessage() != "" {
 		minimalRun.HeadCommit = &MinimalWorkflowRunHeadCommit{
-			Message: sanitize.Sanitize(headCommit.GetMessage()),
+			Message: sanitize.Content(headCommit.GetMessage()),
 		}
 	}
 
@@ -2280,7 +2280,7 @@ func convertToMinimalReviewThread(thread reviewThreadNode) MinimalReviewThread {
 
 func convertToMinimalReviewComment(c reviewCommentNode) MinimalReviewComment {
 	m := MinimalReviewComment{
-		Body:    sanitize.Sanitize(string(c.Body)),
+		Body:    sanitize.Content(string(c.Body)),
 		Path:    string(c.Path),
 		Author:  string(c.Author.Login),
 		HTMLURL: c.URL.String(),

pkg/github/projects.go

@@ -266,7 +266,7 @@ func convertToMinimalStatusUpdate(node statusUpdateNode) MinimalProjectStatusUpd
 
 	return MinimalProjectStatusUpdate{
 		ID:         fmt.Sprintf("%v", node.ID),
-		Body:       sanitize.Sanitize(derefString(node.Body)),
+		Body:       sanitize.Content(derefString(node.Body)),
 		Status:     derefString(node.Status),
 		CreatedAt:  node.CreatedAt.Time.Format(time.RFC3339),
 		StartDate:  derefString(node.StartDate),

pkg/github/repositories.go

@@ -2233,6 +2233,7 @@ func GetLatestRelease(t translations.TranslationHelperFunc) inventory.ServerTool
 				return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to get latest release", resp, body), nil, nil
 			}
 
+			sanitizeReleaseNameAndBody(release)
 			r, err := json.Marshal(release)
 			if err != nil {
 				return nil, nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -2319,6 +2320,7 @@ func GetReleaseByTag(t translations.TranslationHelperFunc) inventory.ServerTool
 				return ghErrors.NewGitHubAPIStatusErrorResponse(ctx, "failed to get release by tag", resp, body), nil, nil
 			}
 
+			sanitizeReleaseNameAndBody(release)
 			r, err := json.Marshal(release)
 			if err != nil {
 				return nil, nil, fmt.Errorf("failed to marshal response: %w", err)
@@ -2338,6 +2340,18 @@ func GetReleaseByTag(t translations.TranslationHelperFunc) inventory.ServerTool
 	)
 }
 
+func sanitizeReleaseNameAndBody(release *github.RepositoryRelease) {
+	if release == nil {
+		return
+	}
+	if release.Name != nil {
+		release.Name = github.Ptr(sanitize.Sanitize(*release.Name))
+	}
+	if release.Body != nil {
+		release.Body = github.Ptr(sanitize.Content(*release.Body))
+	}
+}
+
 // ListStarredRepositories creates a tool to list starred repositories for the authenticated user or a specified user.
 func ListStarredRepositories(t translations.TranslationHelperFunc) inventory.ServerTool {
 	return NewTool(
@@ -2981,7 +2995,7 @@ func GetFileBlame(t translations.TranslationHelperFunc) inventory.ServerTool {
 					SHA: sha,
 					// Sanitized after truncation so the headline is cut at the author's real
 					// first line break rather than one introduced by sanitization.
-					MessageHeadline: sanitize.Sanitize(headline),
+					MessageHeadline: sanitize.Content(headline),
 					CommittedDate:   r.Commit.CommittedDate.Format("2006-01-02T15:04:05Z"),
 					Author: BlameAuthor{
 						Name:  string(r.Commit.Author.Name),

pkg/github/repositories_test.go

@@ -4926,6 +4926,29 @@ func Test_GetLatestRelease(t *testing.T) {
 	}
 }
 
+func Test_GetLatestRelease_SanitizesNameAndBody(t *testing.T) {
+	serverTool := GetLatestRelease(translations.NullTranslationHelper)
+	mockRelease := &github.RepositoryRelease{
+		TagName: "v1.0.0",
+		Name:    github.Ptr(maliciousText),
+		Body:    github.Ptr(maliciousText),
+	}
+	client := mustNewGHClient(t, NewMockedHTTPClient(
+		WithRequestMatch(GetReposReleasesLatestByOwnerByRepo, mockRelease),
+	))
+	deps := BaseDeps{Client: client}
+	handler := serverTool.Handler(deps)
+	request := createMCPRequest(map[string]any{"owner": "owner", "repo": "repo"})
+
+	result, err := handler(ContextWithDeps(context.Background(), deps), &request)
+	require.NoError(t, err)
+
+	var release github.RepositoryRelease
+	require.NoError(t, json.Unmarshal([]byte(getTextResult(t, result).Text), &release))
+	assert.Equal(t, sanitizedText, release.GetName())
+	assert.Equal(t, sanitizedContentText, release.GetBody())
+}
+
 func Test_GetReleaseByTag(t *testing.T) {
 	serverTool := GetReleaseByTag(translations.NullTranslationHelper)
 	tool := serverTool.Tool
@@ -5097,6 +5120,33 @@ func Test_GetReleaseByTag(t *testing.T) {
 	}
 }
 
+func Test_GetReleaseByTag_SanitizesNameAndBody(t *testing.T) {
+	serverTool := GetReleaseByTag(translations.NullTranslationHelper)
+	mockRelease := &github.RepositoryRelease{
+		TagName: "v1.0.0",
+		Name:    github.Ptr(maliciousText),
+		Body:    github.Ptr(maliciousText),
+	}
+	client := mustNewGHClient(t, NewMockedHTTPClient(
+		WithRequestMatch(GetReposReleasesTagsByOwnerByRepoByTag, mockRelease),
+	))
+	deps := BaseDeps{Client: client}
+	handler := serverTool.Handler(deps)
+	request := createMCPRequest(map[string]any{
+		"owner": "owner",
+		"repo":  "repo",
+		"tag":   "v1.0.0",
+	})
+
+	result, err := handler(ContextWithDeps(context.Background(), deps), &request)
+	require.NoError(t, err)
+
+	var release github.RepositoryRelease
+	require.NoError(t, json.Unmarshal([]byte(getTextResult(t, result).Text), &release))
+	assert.Equal(t, sanitizedText, release.GetName())
+	assert.Equal(t, sanitizedContentText, release.GetBody())
+}
+
 // Test_GetReleaseByTag_IFC_FeatureFlag verifies the IFC label on
 // get_release_by_tag. The label is only present when the ifc_labels flag is
 // enabled, and confidentiality is public only for a non-draft release on a
@@ -6200,7 +6250,7 @@ func Test_GetFileBlame(t *testing.T) {
 				var br BlameResult
 				require.NoError(t, json.Unmarshal([]byte(result), &br))
 				require.Contains(t, br.Commits, "badc0ffee0000")
-				assert.Equal(t, sanitizedText, br.Commits["badc0ffee0000"].MessageHeadline)
+				assert.Equal(t, sanitizedContentText, br.Commits["badc0ffee0000"].MessageHeadline)
 				assert.NotContains(t, result, "<script>")
 				assert.NotContains(t, result, "Long body that should not appear")
 			},