Error uploading document to Mistral OCR API The server responded with status 400

[xoChrisCo]

What happened?

When using the Mistral OCR, I am able to upload PDF documents, but png or jpg files seems to all be getting this error:

2025-03-27T21:36:20.424Z error: Error performing OCR:
2025-03-27T21:36:20.424Z error: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status code 400
2025-03-27T21:36:20.425Z error: [/files/images] Error processing file: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status co... [truncated]
2025-03-27T21:36:20.426Z error: [/files/images] Error deleting file: ENOENT: no such file or directory, unlink '/app/client/public/images/67d098d9f2732eca1bba6719/image002_119723_.pn... [truncated]
2025-03-27T21:36:20.427Z debug: [/files/images] Temp. image upload file deleted

Version Information

root@fsn-labs-fsn:~# docker images | grep librechat
ghcr.io/danny-avila/librechat-dev-api latest 81fbd6c27f64 6 hours ago 1.04GB

Steps to Reproduce

1. Set the following .env variables: OCR_API_KEY, OCR_BASEURL (I needed to set this, or else it didn't work. Even when the documentation says you can just let it default),
2. Open agent builder. Upload a pdf to the OCR function. This works.
3. Then try to upload a png or a jpg. And you get this error:

2025-03-28T00:02:31.031Z error: Error performing OCR:
2025-03-28T00:02:31.032Z error: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status code 400
2025-03-28T00:02:31.033Z error: [/files/images] Error processing file: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status co... [truncated]
2025-03-28T00:02:31.034Z error: [/files/images] Error deleting file: ENOENT: no such file or directory, unlink '/app/client/public/images/67d098d9f2732eca1bba6719/23623958.png'
2025-03-28T00:02:31.036Z debug: [/files/images] Temp. image upload file deleted

What browsers are you seeing the problem on?

No response

Relevant log output

{
   "level":"error",
   "message":"Error performing OCR:"
}{
   "data":{
      "code":"1901",
      "message":"Invalid document type. image/png is not supported.",
      "object":"error",
      "param":null,
      "type":"invalid_file"
   },
   "headers":{
      "access-control-allow-origin":"*",
      "alt-svc":"h3=\":443\"; ma=86400",
      "cf-cache-status":"DYNAMIC",
      "cf-ray":"9272dbef2c069176-FRA",
      "connection":"keep-alive",
      "content-length":"130",
      "content-type":"application/json",
      "date":"Fri, 28 Mar 2025 00:02:31 GMT",
      "ratelimitbysize-limit":"2000000",
      "ratelimitbysize-query-cost":"0",
      "ratelimitbysize-remaining":"2000000",
      "ratelimitbysize-reset":"30",
      "server":"cloudflare",
      "set-cookie":"__cf_bm=QXHiyjSRsJTT7u9wkoQMrJf9qISFQSZ47U8kMboV97A-1743120151-1.0.1.1-Lf_o3ksNvAL1LteUndBWAliTQaNOnxZ9_DOKr4GhgGvuZqAGyV0QgeGK1nS6j.4BKPzwXTlt4uE0F0I._0BfEo1Inxd78MD4GiDHODUH7RM; path=/; expires=Fri, 28-Mar-25 00:32:31 GMT; domain=.mistral.ai; HttpOnly; Secure; SameSite=None",
      "x-envoy-upstream-service-time":"74",
      "x-kong-proxy-latency":"5",
      "x-kong-request-id":"227442353f0b2762a999375e46c81047",
      "x-kong-upstream-latency":"75",
      "x-ratelimitbysize-limit-minute":"2000000",
      "x-ratelimitbysize-limit-month":"10000000000",
      "x-ratelimitbysize-remaining-minute":"2000000",
      "x-ratelimitbysize-remaining-month":"10000000000"
   },
   "level":"error",
   "message":"Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status code 400",
   "stack":"AxiosError: Request failed with status code 400\n    at settle (/app/node_modules/axios/dist/node/axios.cjs:2031:12)\n    at IncomingMessage.handleStreamEnd (/app/node_modules/axios/dist/node/axios.cjs:3148:11)\n    at IncomingMessage.emit (node:events:536:35)\n    at endReadableNT (node:internal/streams/readable:1698:12)\n    at process.processTicksAndRejections (node:internal/process/task_queues:82:21)\n    at Axios.request (/app/node_modules/axios/dist/node/axios.cjs:4258:41)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async uploadMistralOCR (/app/api/server/services/Files/MistralOCR/crud.js:163:23)\n    at async processAgentFileUpload (/app/api/server/services/Files/process.js:535:9)\n    at async /app/api/server/routes/files/images.js:24:14",
   "status":400
}{
   "level":"error",
   "message":"[/files/images] Error processing file: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status code 400",
   "stack":"Error: Error uploading document to Mistral OCR API The server responded with status 400: Request failed with status code 400\n    at uploadMistralOCR (/app/api/server/services/Files/MistralOCR/crud.js:197:11)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async processAgentFileUpload (/app/api/server/services/Files/process.js:535:9)\n    at async /app/api/server/routes/files/images.js:24:14"
}{
   "code":"ENOENT",
   "errno":-2,
   "level":"error",
   "message":"[/files/images] Error deleting file: ENOENT: no such file or directory, unlink '/app/client/public/images/67d098d9f2732eca1bba6719/23623958.png'",
   "path":"/app/client/public/images/67d098d9f2732eca1bba6719/23623958.png",
   "stack":"Error: ENOENT: no such file or directory, unlink '/app/client/public/images/67d098d9f2732eca1bba6719/23623958.png'\n    at async Object.unlink (node:internal/fs/promises:1070:10)\n    at async /app/api/server/routes/files/images.js:37:7",
   "syscall":"unlink"
}

Screenshots

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[danny-avila]

The error is clear from the service:

   "data":{
      "code":"1901",
      "message":"Invalid document type. image/png is not supported.",
      "object":"error",
      "param":null,
      "type":"invalid_file"
   },

[xoChrisCo]

Thank you for the answer! I apologize - I should have been clearer in the error issue report.

My question is really - is this something I can fix on my end? As I understand, Mistral should support png, jpg and other formats just fine. And reading through the LibreChat documentation, it seems like images is one of the prime use-cases for this.

[menardorama]

and if I create a png in a pdf it just works

[menardorama]

Looking at the code it seems that pdf upload is the only method supported https://github.com/danny-avila/LibreChat/blob/main/api/server/services/Files/MistralOCR/crud.js

[danny-avila]

Overlooked image uploads but will add them.