import { StructuredTool } from "@langchain/core/tools";
import { CallbackManagerForToolRun } from "@langchain/core/callbacks/manager";
import { z } from "zod";
import SnapRender from "snaprender";
function getClient(apiKey?: string): SnapRender {
const key = apiKey ?? process.env.SNAPRENDER_API_KEY;
if (!key) {
throw new Error(
"SNAPRENDER_API_KEY environment variable is required. " +
"Get a free key at https://app.snap-render.com/auth/signup",
);
}
return new SnapRender({ apiKey: key });
}
// --- Screenshot Tool ---
const screenshotSchema = z.object({
url: z.string().describe("URL to capture (must start with http:// or https://)"),
format: z
.enum(["png", "jpeg", "webp", "pdf"])
.optional()
.default("png")
.describe("Output format"),
full_page: z
.boolean()
.optional()
.default(false)
.describe("Capture entire scrollable page"),
dark_mode: z
.boolean()
.optional()
.default(false)
.describe("Enable dark mode CSS emulation"),
block_ads: z
.boolean()
.optional()
.default(true)
.describe("Block advertisements"),
block_cookie_banners: z
.boolean()
.optional()
.default(true)
.describe("Remove cookie consent banners"),
device: z
.enum(["iphone_14", "iphone_15_pro", "pixel_7", "ipad_pro", "macbook_pro"])
.optional()
.describe("Device preset for viewport emulation"),
width: z.number().optional().describe("Viewport width in pixels (320-3840)"),
height: z.number().optional().describe("Viewport height in pixels (200-10000)"),
});
export interface SnapRenderToolParams {
apiKey?: string;
}
export class SnapRenderScreenshot extends StructuredTool {
static lc_name() {
return "SnapRenderScreenshot";
}
name = "take_screenshot";
description =
"Capture a screenshot of any website as PNG, JPEG, WebP, or PDF. " +
"Supports device emulation, dark mode, ad blocking, and full-page capture.";
schema = screenshotSchema;
private apiKey?: string;
constructor(params: SnapRenderToolParams = {}) {
super();
this.apiKey = params.apiKey;
}
async _call(
input: z.output<typeof screenshotSchema>,
_runManager?: CallbackManagerForToolRun,
): Promise<string> {
const client = getClient(this.apiKey);
const result = await client.capture({
url: input.url,
format: input.format,
fullPage: input.full_page,
darkMode: input.dark_mode,
blockAds: input.block_ads,
blockCookieBanners: input.block_cookie_banners,
device: input.device,
width: input.width,
height: input.height,
responseType: "json",
});
return [
`URL: ${result.url}`,
`Format: ${result.format}`,
`Size: ${result.size.toLocaleString()} bytes`,
`Dimensions: ${result.width}x${result.height}`,
`Cache: ${result.cache}`,
`Response time: ${result.responseTime}`,
`Remaining credits: ${result.remainingCredits}`,
`Image: data:image/${result.format};base64,${result.image.split(",").pop()}`,
].join("\n");
}
}
// --- Cache Check Tool ---
const cacheSchema = z.object({
url: z.string().describe("URL to check"),
format: z
.enum(["png", "jpeg", "webp", "pdf"])
.optional()
.default("png")
.describe("Output format"),
});
export class SnapRenderCacheCheck extends StructuredTool {
static lc_name() {
return "SnapRenderCacheCheck";
}
name = "check_screenshot_cache";
description =
"Check if a screenshot is already cached without capturing a new one. " +
"Free, does not count against quota.";
schema = cacheSchema;
private apiKey?: string;
constructor(params: SnapRenderToolParams = {}) {
super();
this.apiKey = params.apiKey;
}
async _call(
input: z.output<typeof cacheSchema>,
_runManager?: CallbackManagerForToolRun,
): Promise<string> {
const client = getClient(this.apiKey);
const info = await client.info({ url: input.url, format: input.format });
if (info.cached) {
return [
`Cached: YES`,
`URL: ${info.url}`,
`Cached at: ${info.cachedAt ?? "unknown"}`,
`Expires at: ${info.expiresAt ?? "unknown"}`,
`Content type: ${info.contentType ?? "unknown"}`,
].join("\n");
}
return `Cached: NO\nURL: ${info.url}`;
}
}
// --- Usage Tool ---
const usageSchema = z.object({});
export class SnapRenderUsage extends StructuredTool {
static lc_name() {
return "SnapRenderUsage";
}
name = "get_screenshot_usage";
description =
"Get current month's screenshot usage statistics including plan, used, limit, and remaining credits.";
schema = usageSchema;
private apiKey?: string;
constructor(params: SnapRenderToolParams = {}) {
super();
this.apiKey = params.apiKey;
}
async _call(
_input: z.output<typeof usageSchema>,
_runManager?: CallbackManagerForToolRun,
): Promise<string> {
const client = getClient(this.apiKey);
const usage = await client.usage();
return [
`Plan: ${usage.plan}`,
`Used: ${usage.used}`,
`Limit: ${usage.limit}`,
`Remaining: ${usage.remaining}`,
`Period: ${usage.period.start} to ${usage.period.end}`,
].join("\n");
}
}
