diff --git a/cmd/gitea-mcp/main.go b/cmd/gitea-mcp/main.go
index 9313bd8..dde8a6f 100644
--- a/cmd/gitea-mcp/main.go
+++ b/cmd/gitea-mcp/main.go
@@ -39,6 +39,7 @@ func main() {
 	reg.Register(tools.NewCodeSearch(giteaClient, ownerAllow))
 	reg.Register(tools.NewIssueCreate(giteaClient, ownerAllow))
 	reg.Register(tools.NewIssueComment(giteaClient, ownerAllow))
+	reg.Register(tools.NewPRComment(giteaClient, ownerAllow))
 
 	mcpSrv := mcp.NewServer(mcp.ServerOptions{
 		Registry: reg,
diff --git a/internal/tools/pr_comment.go b/internal/tools/pr_comment.go
new file mode 100644
index 0000000..32c1c52
--- /dev/null
+++ b/internal/tools/pr_comment.go
@@ -0,0 +1,73 @@
+package tools
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/auth"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/gitea"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/identity"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/registry"
+)
+
+type PRComment struct {
+	c *gitea.Client
+	a *allowlist.Allowlist
+}
+
+func NewPRComment(c *gitea.Client, a *allowlist.Allowlist) *PRComment {
+	return &PRComment{c: c, a: a}
+}
+
+func (t *PRComment) Descriptor() registry.ToolDescriptor {
+	return registry.ToolDescriptor{
+		Name:        "pr_comment",
+		Description: "Comment on a pull request (conversation, not inline review). Applies identity footer.",
+		InputSchema: json.RawMessage(`{
+			"type":"object",
+			"properties":{
+				"owner":{"type":"string"},
+				"name":{"type":"string"},
+				"number":{"type":"integer","minimum":1},
+				"body":{"type":"string"}
+			},
+			"required":["owner","name","number","body"]
+		}`),
+	}
+}
+
+type prCommentArgs struct {
+	Owner  string `json:"owner"`
+	Name   string `json:"name"`
+	Number int    `json:"number"`
+	Body   string `json:"body"`
+}
+
+func (t *PRComment) Call(ctx context.Context, raw json.RawMessage) (json.RawMessage, error) {
+	var args prCommentArgs
+	if err := parseArgs(raw, &args); err != nil {
+		return nil, err
+	}
+	if err := t.a.Check(args.Owner); err != nil {
+		return nil, err
+	}
+	if args.Number < 1 {
+		return nil, fmt.Errorf("number must be >= 1: %w", gitea.ErrValidation)
+	}
+	if args.Body == "" {
+		return nil, fmt.Errorf("body is required: %w", gitea.ErrValidation)
+	}
+	body := identity.ApplyFooter(args.Body, auth.Caller(ctx))
+
+	c, err := t.c.CreateIssueComment(ctx, args.Owner, args.Name, args.Number, body)
+	if err != nil {
+		return nil, err
+	}
+
+	return textOK(map[string]any{
+		"id":       c.ID,
+		"html_url": c.HTMLURL,
+	})
+}
diff --git a/internal/tools/pr_comment_test.go b/internal/tools/pr_comment_test.go
new file mode 100644
index 0000000..c14ac41
--- /dev/null
+++ b/internal/tools/pr_comment_test.go
@@ -0,0 +1,53 @@
+package tools_test
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/gitea"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/tools"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPRCommentAppliesFooter(t *testing.T) {
+	var captured []byte
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// PRs share index space with issues — same endpoint
+		assert.Equal(t, "/api/v1/repos/o/r/issues/3/comments", r.URL.Path)
+		var err error
+		captured, err = io.ReadAll(r.Body)
+		require.NoError(t, err)
+		w.WriteHeader(http.StatusCreated)
+		_, _ = w.Write([]byte(commentFixture))
+	}))
+	defer srv.Close()
+
+	tool := tools.NewPRComment(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"o"}))
+	ctx := callerContext("mathiasbq")
+	_, err := tool.Call(ctx, json.RawMessage(`{"owner":"o","name":"r","number":3,"body":"looks good"}`))
+	require.NoError(t, err)
+
+	var payload map[string]any
+	require.NoError(t, json.Unmarshal(captured, &payload))
+	body, _ := payload["body"].(string)
+	assert.Contains(t, body, "_Created via git-mcp on behalf of @mathiasbq_")
+}
+
+func TestPRCommentAllowlistRejects(t *testing.T) {
+	tool := tools.NewPRComment(gitea.NewClient("http://unused", ""), allowlist.New([]string{"allowed"}))
+	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"evil","name":"r","number":1,"body":"hi"}`))
+	require.Error(t, err)
+}
+
+func TestPRCommentRequiresBody(t *testing.T) {
+	tool := tools.NewPRComment(gitea.NewClient("http://unused", ""), allowlist.New([]string{"o"}))
+	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"o","name":"r","number":1,"body":""}`))
+	require.Error(t, err)
+	assert.ErrorIs(t, err, gitea.ErrValidation)
+}