feat: P0 LLM-readiness — Chrome aislado (9333), tab_select determinista, page_get_text, page_perceive

tools_read.go

@@ -2,6 +2,10 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"os/exec"
+	"path/filepath"
+	"strings"
 
 	"github.com/mark3labs/mcp-go/mcp"
 	"github.com/mark3labs/mcp-go/server"
@@ -11,9 +15,12 @@ import (
 
 const htmlMax = 200_000
 
-// registerReadTools wires page_get_html, page_eval_js (MUTA), page_screenshot.
+// registerReadTools wires page_get_html, page_get_text, page_perceive,
+// page_eval_js (MUTA), page_screenshot.
 func registerReadTools(s *server.MCPServer, d *deps) {
 	s.AddTool(pageGetHTMLTool(), mcp.NewTypedToolHandler(d.handlePageGetHTML))
+	s.AddTool(pageGetTextTool(), mcp.NewTypedToolHandler(d.handlePageGetText))
+	s.AddTool(pagePerceiveTool(), mcp.NewTypedToolHandler(d.handlePagePerceive))
 	s.AddTool(pageScreenshotTool(), mcp.NewTypedToolHandler(d.handlePageScreenshot))
 
 	if !d.readOnly {
@@ -21,6 +28,105 @@ func registerReadTools(s *server.MCPServer, d *deps) {
 	}
 }
 
+// ---- page_get_text ----
+
+type pageGetTextArgs struct {
+	Port     int    `json:"port"`
+	Selector string `json:"selector"`
+	MaxBytes int    `json:"max_bytes"`
+}
+
+func pageGetTextTool() mcp.Tool {
+	return mcp.NewTool("page_get_text",
+		mcp.WithDescription("Devuelve el texto visible (innerText) de la página o de un elemento (selector CSS), truncado a max_bytes. Preferir sobre page_get_html cuando solo necesitas leer contenido — no revienta el contexto."),
+		mcp.WithNumber("port", mcp.Description("CDP port. Default 9333 (Chrome isolated del MCP); usa 9222 explícito solo para adjuntarte al navegador diario.")),
+		mcp.WithString("selector", mcp.Description("Selector CSS opcional. Vacío = body (toda la página).")),
+		mcp.WithNumber("max_bytes", mcp.Description("Máximo de bytes a devolver. Default 20000. 0 = sin límite.")),
+	)
+}
+
+func (d *deps) handlePageGetText(_ context.Context, _ mcp.CallToolRequest, a pageGetTextArgs) (*mcp.CallToolResult, error) {
+	maxBytes := a.MaxBytes
+	if maxBytes == 0 {
+		maxBytes = 20000
+	}
+	var text string
+	err := d.withConn(portOr(a.Port), func(c *browser.CDPConn) error {
+		var e error
+		text, e = browser.CdpGetText(c, a.Selector, maxBytes)
+		return e
+	})
+	if err != nil {
+		return mcp.NewToolResultError(err.Error()), nil
+	}
+	return mcp.NewToolResultText(text), nil
+}
+
+// ---- page_perceive ----
+
+type pagePerceiveArgs struct {
+	Port     int    `json:"port"`
+	TabID    string `json:"tab_id"`
+	MaxChars int    `json:"max_chars"`
+}
+
+func pagePerceiveTool() mcp.Tool {
+	return mcp.NewTool("page_perceive",
+		mcp.WithDescription("Devuelve un outline indentado y accionable del árbol de accesibilidad (roles, nombres, #ref) — la forma compacta de que el agente 'perciba' la página sin reventar el contexto. Si tab_id se omite, usa la primera pestaña page. Gotcha: requiere el binario `fn` y el venv de Python del registry disponibles en runtime."),
+		mcp.WithNumber("port", mcp.Description("CDP port. Default 9333 (Chrome isolated del MCP); usa 9222 explícito solo para adjuntarte al navegador diario.")),
+		mcp.WithString("tab_id", mcp.Description("Target id de la pestaña. Vacío = primera pestaña page.")),
+		mcp.WithNumber("max_chars", mcp.Description("Máximo de chars del outline. Default 20000.")),
+	)
+}
+
+func (d *deps) handlePagePerceive(_ context.Context, _ mcp.CallToolRequest, a pagePerceiveArgs) (*mcp.CallToolResult, error) {
+	port := portOr(a.Port)
+	maxChars := a.MaxChars
+	if maxChars == 0 {
+		maxChars = 20000
+	}
+
+	root, err := resolveRoot()
+	if err != nil {
+		return mcp.NewToolResultError("resolve registry root: " + err.Error()), nil
+	}
+
+	tabID := a.TabID
+	if tabID == "" {
+		tabs, err := browser.CdpListTabs("localhost", port)
+		if err != nil {
+			return mcp.NewToolResultError("list tabs: " + err.Error()), nil
+		}
+		for _, t := range tabs {
+			if t.Type == "page" {
+				tabID = t.ID
+				break
+			}
+		}
+		if tabID == "" {
+			return mcp.NewToolResultError("no 'page' tab found on port " + fmt.Sprint(port)), nil
+		}
+	}
+
+	cmd := exec.Command(filepath.Join(root, "fn"), "run", "cdp_perceive_outline",
+		"--debug-port", fmt.Sprint(port),
+		"--tab-id", tabID,
+		"--max-chars", fmt.Sprint(maxChars),
+	)
+	cmd.Dir = root
+	var stdout, stderr strings.Builder
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
+	if err := cmd.Run(); err != nil {
+		msg := strings.TrimSpace(stderr.String())
+		if msg == "" {
+			msg = err.Error()
+		}
+		return mcp.NewToolResultError("cdp_perceive_outline failed: " + msg), nil
+	}
+	return mcp.NewToolResultText(truncate(stdout.String(), htmlMax)), nil
+}
+
 // ---- page_get_html ----
 
 type pageGetHTMLArgs struct {