Files
mcp-captcharesolver/internal/mcp/tools.go
T

186 lines
7.2 KiB
Go

// Package mcpserver wires captcha + stealth functions to MCP tools.
package mcpserver
import (
"context"
"errors"
"fmt"
"github.com/modelcontextprotocol/go-sdk/mcp"
"github.com/lukaszraczylo/captcha-solver-mcp/internal/captcha"
"github.com/lukaszraczylo/captcha-solver-mcp/internal/imageutil"
"github.com/lukaszraczylo/captcha-solver-mcp/internal/llm"
"github.com/lukaszraczylo/captcha-solver-mcp/internal/stealth"
)
// Handlers holds dependencies shared by all tool handlers.
type Handlers struct {
llm llm.Client
provider string
model string
}
// New constructs Handlers.
func New(c llm.Client, provider, model string) *Handlers {
return &Handlers{llm: c, provider: provider, model: model}
}
// ---- detect_captcha ----
type DetectIn struct {
HTML string `json:"html,omitempty" jsonschema:"page HTML to scan for captcha markers"`
URL string `json:"url,omitempty" jsonschema:"page URL (informational)"`
Screenshot string `json:"screenshot,omitempty" jsonschema:"base64/path/url screenshot, used only if HTML is inconclusive"`
}
type DetectOut struct {
Detected []captcha.Detection `json:"detected"`
Summary string `json:"summary"`
}
func (h *Handlers) detect(_ context.Context, _ *mcp.CallToolRequest, in DetectIn) (*mcp.CallToolResult, DetectOut, error) {
det := captcha.DetectHTML(in.HTML)
summary := fmt.Sprintf("%d captcha(s) detected", len(det))
return nil, DetectOut{Detected: det, Summary: summary}, nil
}
// ---- solve_text_captcha ----
type SolveTextIn struct {
Image string `json:"image" jsonschema:"base64/path/url/data-uri of the text captcha image"`
Hint string `json:"hint,omitempty"`
Charset string `json:"charset,omitempty"`
Length int `json:"length,omitempty"`
CaseSensitive bool `json:"case_sensitive,omitempty"`
}
func (h *Handlers) solveText(ctx context.Context, _ *mcp.CallToolRequest, in SolveTextIn) (*mcp.CallToolResult, captcha.TextResult, error) {
data, mt, err := imageutil.Decode(in.Image)
if err != nil {
return nil, captcha.TextResult{}, err
}
res, err := captcha.SolveText(ctx, h.llm, data, mt, captcha.TextOptions{
Hint: in.Hint, Charset: in.Charset, Length: in.Length, CaseSensitive: in.CaseSensitive,
})
return nil, res, err
}
// ---- solve_audio_captcha ----
type SolveAudioIn struct {
Audio string `json:"audio" jsonschema:"base64/path/url of the audio captcha"`
Language string `json:"language,omitempty"`
}
func (h *Handlers) solveAudio(ctx context.Context, _ *mcp.CallToolRequest, in SolveAudioIn) (*mcp.CallToolResult, captcha.AudioResult, error) {
data, _, err := imageutil.Decode(in.Audio)
if err != nil {
return nil, captcha.AudioResult{}, err
}
res, err := captcha.SolveAudio(ctx, h.llm, data, "audio.wav", in.Language)
var unsupported llm.ErrUnsupported
if errors.As(err, &unsupported) {
return nil, captcha.AudioResult{}, fmt.Errorf("audio captcha unsupported: configured provider %q has no transcription; set CAPTCHA_LLM_PROVIDER=openai|gemini and CAPTCHA_LLM_AUDIO_MODEL", h.provider)
}
return nil, res, err
}
// ---- solve_grid_captcha ----
type SolveGridIn struct {
Screenshot string `json:"screenshot" jsonschema:"base64/path/url of the challenge grid image"`
Instruction string `json:"instruction" jsonschema:"the challenge text, e.g. 'select all buses'"`
CaptchaType string `json:"captcha_type,omitempty" jsonschema:"recaptcha | hcaptcha"`
Rows int `json:"rows" jsonschema:"grid rows (e.g. 3)"`
Cols int `json:"cols" jsonschema:"grid cols (e.g. 3)"`
ImageWidth int `json:"image_width,omitempty" jsonschema:"screenshot width in px, enables centroid output"`
ImageHeight int `json:"image_height,omitempty" jsonschema:"screenshot height in px, enables centroid output"`
}
func (h *Handlers) solveGrid(ctx context.Context, _ *mcp.CallToolRequest, in SolveGridIn) (*mcp.CallToolResult, captcha.GridResult, error) {
data, mt, err := imageutil.Decode(in.Screenshot)
if err != nil {
return nil, captcha.GridResult{}, err
}
res, err := captcha.SolveGrid(ctx, h.llm, data, mt, captcha.GridOptions{
Instruction: in.Instruction, CaptchaType: in.CaptchaType,
Rows: in.Rows, Cols: in.Cols, ImageWidth: in.ImageWidth, ImageHeight: in.ImageHeight,
})
return nil, res, err
}
// ---- solve_rotation_captcha ----
type SolveRotationIn struct {
Screenshot string `json:"screenshot" jsonschema:"base64/path/url of the rotation/choice puzzle"`
Instruction string `json:"instruction,omitempty"`
}
func (h *Handlers) solveRotation(ctx context.Context, _ *mcp.CallToolRequest, in SolveRotationIn) (*mcp.CallToolResult, captcha.RotationResult, error) {
data, mt, err := imageutil.Decode(in.Screenshot)
if err != nil {
return nil, captcha.RotationResult{}, err
}
res, err := captcha.SolveRotation(ctx, h.llm, data, mt, in.Instruction)
return nil, res, err
}
// ---- stealth tools ----
type StealthScriptIn struct {
Engine string `json:"engine,omitempty" jsonschema:"playwright | cdp | generic"`
}
func (h *Handlers) stealthScript(_ context.Context, _ *mcp.CallToolRequest, in StealthScriptIn) (*mcp.CallToolResult, stealth.ScriptResult, error) {
return nil, stealth.StealthScript(stealth.ScriptParams{Engine: in.Engine}), nil
}
type FingerprintIn struct {
OS string `json:"os,omitempty" jsonschema:"windows | macos | linux"`
Browser string `json:"browser,omitempty" jsonschema:"chrome | firefox"`
Locale string `json:"locale,omitempty"`
Seed uint64 `json:"seed,omitempty" jsonschema:"seed for a stable identity across runs"`
}
type FingerprintOut struct {
Fingerprint stealth.Fingerprint `json:"fingerprint"`
HeaderSet stealth.HeaderSet `json:"header_set"`
}
func (h *Handlers) fingerprint(_ context.Context, _ *mcp.CallToolRequest, in FingerprintIn) (*mcp.CallToolResult, FingerprintOut, error) {
fp := stealth.GenerateFingerprint(stealth.FingerprintParams{OS: in.OS, Browser: in.Browser, Locale: in.Locale, Seed: in.Seed})
return nil, FingerprintOut{Fingerprint: fp, HeaderSet: stealth.HeadersFor(fp)}, nil
}
type PlanInteractionIn struct {
Actions []stealth.Action `json:"actions" jsonschema:"clicks/types/scrolls to humanize"`
Seed uint64 `json:"seed,omitempty"`
}
func (h *Handlers) planInteraction(_ context.Context, _ *mcp.CallToolRequest, in PlanInteractionIn) (*mcp.CallToolResult, stealth.InteractionPlan, error) {
return nil, stealth.PlanInteraction(stealth.InteractionParams{Actions: in.Actions, Seed: in.Seed}), nil
}
// ---- solver_info ----
type SolverInfoOut struct {
Provider string `json:"provider"`
Model string `json:"model"`
Capabilities map[string]bool `json:"capabilities"`
Notes map[string]string `json:"notes"`
}
func (h *Handlers) solverInfo(_ context.Context, _ *mcp.CallToolRequest, _ struct{}) (*mcp.CallToolResult, SolverInfoOut, error) {
audio := h.provider == "openai" || h.provider == "openai-compatible" || h.provider == "gemini"
return nil, SolverInfoOut{
Provider: h.provider, Model: h.model,
Capabilities: map[string]bool{
"text": true, "grid": true, "rotation": true, "audio": audio, "detect": true,
"stealth": true,
},
Notes: map[string]string{
"recaptcha_v3": "detect-only, not LLM-solvable",
"turnstile": "detect-only, not LLM-solvable",
},
}, nil
}