/**
* Flow Runner - Execute sequences of MCP tool calls
*/
import { logger } from "../core/logger.js";
import { takeScreenshot } from "../simulator/screenshots.js";
import type { FlowStep } from "../mcp/schemas.js";
export interface FlowResult {
success: boolean;
totalSteps: number;
completedSteps: number;
failedStep?: number;
results: StepResult[];
totalElapsedMs: number;
evidence?: string[];
}
export interface StepResult {
step: number;
tool: string;
success: boolean;
elapsedMs: number;
result?: unknown;
error?: string;
}
export type ToolExecutor = (
toolName: string,
input: Record<string, unknown>
) => Promise<{ success: boolean; result?: unknown; error?: string }>;
export async function runFlow(
steps: FlowStep[],
executor: ToolExecutor,
options: {
stopOnError?: boolean;
screenshotOnError?: boolean;
} = {}
): Promise<FlowResult> {
const { stopOnError = true, screenshotOnError = true } = options;
const startTime = Date.now();
const results: StepResult[] = [];
const evidence: string[] = [];
logger.info("expo", `Starting flow with ${steps.length} steps`);
for (let i = 0; i < steps.length; i++) {
const step = steps[i];
const stepNumber = i + 1;
const stepStart = Date.now();
logger.info("expo", `Step ${stepNumber}/${steps.length}: ${step.tool}`, {
description: step.description,
});
try {
const { success, result, error } = await executor(
step.tool,
step.input as Record<string, unknown>
);
const stepResult: StepResult = {
step: stepNumber,
tool: step.tool,
success,
elapsedMs: Date.now() - stepStart,
result,
error,
};
results.push(stepResult);
if (!success) {
logger.error("expo", `Step ${stepNumber} failed: ${error}`);
if (screenshotOnError) {
try {
const screenshot = await takeScreenshot(`flow-error-step-${stepNumber}`);
evidence.push(screenshot.path);
} catch {
logger.warn("expo", "Failed to capture error screenshot");
}
}
if (stopOnError) {
return {
success: false,
totalSteps: steps.length,
completedSteps: stepNumber - 1,
failedStep: stepNumber,
results,
totalElapsedMs: Date.now() - startTime,
evidence: evidence.length > 0 ? evidence : undefined,
};
}
} else {
logger.info("expo", `Step ${stepNumber} completed in ${stepResult.elapsedMs}ms`);
}
} catch (err) {
const stepResult: StepResult = {
step: stepNumber,
tool: step.tool,
success: false,
elapsedMs: Date.now() - stepStart,
error: err instanceof Error ? err.message : "Unknown error",
};
results.push(stepResult);
if (screenshotOnError) {
try {
const screenshot = await takeScreenshot(`flow-error-step-${stepNumber}`);
evidence.push(screenshot.path);
} catch {
// Ignore screenshot errors
}
}
if (stopOnError) {
return {
success: false,
totalSteps: steps.length,
completedSteps: stepNumber - 1,
failedStep: stepNumber,
results,
totalElapsedMs: Date.now() - startTime,
evidence: evidence.length > 0 ? evidence : undefined,
};
}
}
}
const allSuccess = results.every((r) => r.success);
logger.info("expo", `Flow completed: ${allSuccess ? "SUCCESS" : "FAILED"}`, {
totalSteps: steps.length,
completedSteps: results.filter((r) => r.success).length,
totalElapsedMs: Date.now() - startTime,
});
return {
success: allSuccess,
totalSteps: steps.length,
completedSteps: results.filter((r) => r.success).length,
failedStep: allSuccess ? undefined : results.findIndex((r) => !r.success) + 1,
results,
totalElapsedMs: Date.now() - startTime,
evidence: evidence.length > 0 ? evidence : undefined,
};
}
