vercel/ai · error · UnsupportedFunctionalityError

file parts with provider references

Error message

file parts with provider references

What it means

Perplexity's message format cannot express file parts whose data is a provider reference (a pointer to a previously uploaded/generated file). convertToPerplexityMessages throws UnsupportedFunctionalityError for part.data.type === 'reference' because there is no Perplexity representation to map it to.

Source

Thrown at packages/perplexity/src/convert-to-perplexity-messages.ts:49

            (part.type === 'file' &&
              getTopLevelMediaType(part.mediaType) === 'image') ||
            (part.type === 'file' &&
              getTopLevelMediaType(part.mediaType) === 'application'),
        );

        const messageContent = content
          .map((part, index) => {
            switch (part.type) {
              case 'text': {
                return {
                  type: 'text',
                  text: part.text,
                };
              }
              case 'file': {
                switch (part.data.type) {
                  case 'reference': {
                    throw new UnsupportedFunctionalityError({
                      functionality: 'file parts with provider references',
                    });
                  }
                  case 'text': {
                    throw new UnsupportedFunctionalityError({
                      functionality: 'text file parts',
                    });
                  }
                  case 'url':
                  case 'data': {
                    const topLevelMediaType = getTopLevelMediaType(
                      part.mediaType,
                    );

                    if (topLevelMediaType === 'application') {
                      const fullMediaType = resolveFullMediaType({ part });

                      if (fullMediaType !== 'application/pdf') {

View on GitHub (pinned to 69428b1f8b)

Solutions

1. Inline the actual file bytes as a data part (base64 data URL) instead of a reference
2. Provide the file as a URL part that Perplexity can fetch
3. Strip or convert reference file parts before calling Perplexity

Example fix

// before
{ type: 'file', data: { type: 'reference', fileId } }
// after
{ type: 'file', data: new URL('https://example.com/doc.pdf'), mediaType: 'application/pdf' }

for (const msg of messages) {
  for (const part of msg.content) {
    if (part.type === 'file' && part.data?.type === 'reference') {
      throw new Error('Perplexity cannot consume file parts with provider references; inline data or use a URL');
    }
  }
}

function isReferencedFilePart(part: { type: string; data?: { type?: string } }): boolean {
  return part.type === 'file' && part.data?.type === 'reference';
}

try {
  await generateText({ model: perplexity('sonar-pro'), messages });
} catch (e) {
  if (UnsupportedFunctionalityError.isInstance(e) && e.message.includes('provider references')) {
    // rebuild messages with inlined data/URL file parts
  } else throw e;
}

When it happens

Trigger: Sending a prompt whose messages contain a file part created with a provider-generated reference (e.g. data from a prior generateImage/file upload returned as { type: 'reference', ... }) to a perplexity.chat(...) model.

Common situations: Chaining outputs between providers (OpenAI file ids or previously generated assets passed to Perplexity); reusing a shared message history that includes provider-specific file references.

Related errors

• text file parts
• file part media type ${fullMediaType}
• AI_UnsupportedFunctionalityError
• file parts with provider references
• File URL data

AI-assisted analysis of vercel/ai@69428b1f8b (2026-08-30). Data as JSON: /api/errors/40f887ca59580227. Report an issue: GitHub.