eyaltoledano/claude-task-master · error

User prompt content is missing.

Error message

User prompt content is missing.

What it means

_unifiedServiceRunner builds the message array for the provider call and requires a non-empty user prompt. If the `prompt` parameter is falsy (empty string, undefined, null), it throws instead of sending a request with no user content, which providers would reject anyway.

Source

Thrown at scripts/modules/ai-services-unified.js:667

			//     text: 'Large cached context here like a tasks json',
			//     providerOptions: {
			//       anthropic: { cacheControl: { type: 'ephemeral' } }
			//     }
			//   }

			// Example
			// if (params.context) { // context is a json string of a tasks object or some other stu
			//     messages.push({
			//         type: 'text',
			//         text: params.context,
			//         providerOptions: { anthropic: { cacheControl: { type: 'ephemeral' } } }
			//     });
			// }

			if (prompt) {
				messages.push({ role: 'user', content: prompt });
			} else {
				throw new Error('User prompt content is missing.');
			}

			const callParams = {
				apiKey,
				modelId,
				maxTokens: roleParams.maxTokens,
				temperature: roleParams.temperature,
				messages,
				...(baseURL && { baseURL }),
				...((serviceType === 'generateObject' ||
					serviceType === 'streamObject') && { schema, objectName }),
				...(commandName && { commandName }), // Pass commandName for Sentry telemetry functionId
				...(outputType && { outputType }), // Pass outputType for Sentry telemetry metadata
				...(projectRoot && { projectRoot }), // Pass projectRoot for Sentry telemetry hashing
				...(hamsterUserId && { userId: hamsterUserId }), // Pass Hamster userId if authenticated
				...(hamsterBriefId && { briefId: hamsterBriefId }), // Pass Hamster briefId if connected
				...(experimental_transform && { experimental_transform }), // Pass smoothStream or other transforms
				...providerSpecificParams,

View on GitHub (pinned to c0c98d367c)

Solutions

1. Ensure a non-empty prompt string is passed to the service call.
2. Trace the variable feeding `prompt` and fix why it's empty (missing file content, undefined task).
3. Guard the call site: check prompt && prompt.trim() before invoking, or provide a default prompt.
4. For object services, confirm you're not accidentally passing the object as a different parameter and leaving prompt empty.

Example fix

// before
const prompt = task.description ?? ''; // empty when description missing
await generateTextService({ prompt, ... }); // throws
// after
const prompt = task.description?.trim();
if (!prompt) throw new Error(`Task ${task.id} has no description to analyze`);
await generateTextService({ prompt, ... });

function assertPrompt(prompt) {
  if (typeof prompt !== 'string' || prompt.trim() === '') {
    throw new Error('prompt must be a non-empty string before calling AI services');
  }
  return prompt;
}
await generateTextService({ prompt: assertPrompt(maybePrompt), ... });

function isNonEmptyString(v) {
  return typeof v === 'string' && v.trim().length > 0;
}

try {
  await generateTextService({ prompt, ... });
} catch (e) {
  if (/User prompt content is missing/.test(e.message)) {
    console.error('The prompt was empty — check the data source feeding your prompt template.');
  } else throw e;
}

When it happens

Trigger: Calling generateTextService/generateObjectService/streamTextService/streamObjectService with prompt omitted, or prompt: '' / null / undefined — e.g. when building prompts dynamically from empty variables or template results.

Common situations: Upstream data source returned nothing (empty file, empty task description), template rendering produced an empty string, or a refactor renamed the prompt parameter so it's no longer populated.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• No valid task IDs provided
• Invalid task ID format: ${invalidIds.join(', ')}. Expected n
• Unknown provider '${providerName}' for API key resolution.
• Task ID cannot be empty.
• Prompt cannot be empty unless metadata is provided for updat

AI-assisted analysis of eyaltoledano/claude-task-master@c0c98d367c (2026-08-29). Data as JSON: /api/errors/168abaa96db9fd15. Report an issue: GitHub.