Practice Problem Generator

Choose your subject and difficulty, then generate unlimited AI-powered practice problems with full worked solutions.

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Select a subject and level above, then hit Generate to get your first problem.

\n\n\n\n`;\n\nexport default async function (req: Request): Promise {\n const url = new URL(req.url);\n\n if (req.method === \"GET\" && url.pathname === \"/\") {\n return new Response(HTML, {\n headers: { \"Content-Type\": \"text/html; charset=utf-8\" },\n });\n }\n\n const apiKey = Deno.env.get(\"ANTHROPIC_API_KEY\");\n if (!apiKey) {\n return new Response(\"Missing ANTHROPIC_API_KEY\", { status: 500 });\n }\n\n if (req.method === \"POST\" && url.pathname === \"/problem\") {\n let body: any;\n try {\n body = await req.json();\n } catch {\n return new Response(\"Invalid JSON\", { status: 400 });\n }\n\n const { subject = \"Algebra\", difficulty = \"Beginner\" } = body;\n\n const prompt = `You are an expert educator creating a practice problem.\nSubject: ${subject}\nDifficulty: ${difficulty}\n\nGenerate one multiple-choice practice problem appropriate for this subject and difficulty level.\nMake it specific, well-worded, and educational. For math/science include realistic numbers and context.\n\nReturn ONLY raw JSON with no markdown fences:\n{\n \"question\": \"The full problem statement. Use plain text. For math write expressions like x^2 + 3x - 4 or use words like squared.\",\n \"choices\": [\"choice A text\", \"choice B text\", \"choice C text\", \"choice D text\"],\n \"correctIndex\": 0,\n \"answer\": \"The correct answer with brief justification\",\n \"hint\": \"A helpful nudge that guides without giving away the answer\",\n \"steps\": [\n \"Step 1: what to do and why\",\n \"Step 2: next step\",\n \"Step 3: continue\",\n \"Step 4: final step leading to the answer\"\n ],\n \"points\": 10\n}\n\ncorrectIndex must be 0, 1, 2, or 3. Make sure exactly one choice is correct and the others are plausible but wrong.`;\n\n const r = await fetch(\"https://api.anthropic.com/v1/messages\", {\n method: \"POST\",\n headers: {\n \"Content-Type\": \"application/json\",\n \"x-api-key\": apiKey,\n \"anthropic-version\": \"2023-06-01\",\n },\n body: JSON.stringify({\n model: \"claude-sonnet-4-20250514\",\n max_tokens: 1200,\n messages: [{ role: \"user\", content: prompt }],\n }),\n });\n\n if (!r.ok) {\n return new Response(\"Anthropic error: \" + await r.text(), {\n status: 502,\n });\n }\n const data = await r.json();\n const raw = (data.content as any[]).map((b: any) => b.text || \"\").join(\"\");\n try {\n const parsed = JSON.parse(raw.replace(/```json|```/g, \"\").trim());\n return new Response(JSON.stringify(parsed), {\n headers: { \"Content-Type\": \"application/json\" },\n });\n } catch {\n return new Response(JSON.stringify({ error: \"Parse error\", raw }), {\n status: 500,\n headers: { \"Content-Type\": \"application/json\" },\n });\n }\n }\n\n return new Response(\"Not found\", { status: 404 });\n}","deleted","label",[102],"permalink","https://www.val.town/x/meadrjacob/untitled-9743/code/new-file-2487.ts","extension","actionData","errors"]