Anthropic API error on edit

[lenis0012]

Before submitting your bug report

• I believe this is a bug. I'll try to join the Continue Discord for questions
• I'm not able to find an open issue that reports the same bug
• I've seen the troubleshooting guide on the Continue Docs

Relevant environment info

- OS: Windows 11
- Continue version: 1.0.21
- IDE version: WebStorm 2025.1.1
- Model: Antrhopic Claude 4.0 Sonnet (also happens with others)
- config:
  
models:
  - name: Claude 4.0 Sonnet
    provider: anthropic
    model: claude-sonnet-4-20250514
    apiKey: '<omitted>'
    roles:
      - chat
      - edit
      - apply

Description

When I try to initiate an inline edit, I get the following error:

HTTP 400 Bad Request from https://api.anthropic.com/v1/messages {"type":"error","error":{"type":"invalid_request_error","message":"messages: at least one message is required"}}

However, chat is working fine, so one would think its not related to the model configuration.

To reproduce

No response

Log output

This is the code to rewrite:

function sortingAlgorithm(x: number[]): number[] {
  for (let i = 0; i < x.length; i++) {
    for (let j = 0; j < x.length - 1; j++) {
      if (x[j] > x[j + 1]) {
        let temp = x[j];
        x[j] = x[j + 1];
        x[j + 1] = temp;
      }
    }
  }
  return x;
}


The user's request is: "make this more readable"

DO NOT output any natural language, only output the code changes.

Here is the rewritten code:
[2025-06-03T10:54:42] HTTP 400 Bad Request from https://api.anthropic.com/v1/messages

{"type":"error","error":{"type":"invalid_request_error","message":"messages: at least one message is required"}}

Code: undefined
Error number: undefined
Syscall: undefined
Type: undefined

Error: HTTP 400 Bad Request from https://api.anthropic.com/v1/messages

{"type":"error","error":{"type":"invalid_request_error","message":"messages: at least one message is required"}}
    at n (C:\snapshot\continue\binary\out\index.js:8279:7981)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async JVA (C:\snapshot\continue\binary\out\index.js:8022:5422)
    at async aVt._streamChat (C:\snapshot\continue\binary\out\index.js:9009:2664)
    at async aVt._streamComplete (C:\snapshot\continue\binary\out\index.js:9009:2306)
    at async aVt.streamComplete (C:\snapshot\continue\binary\out\index.js:8295:1437)
    at async PUi (C:\snapshot\continue\binary\out\index.js:9142:4683)
    at async Jle (C:\snapshot\continue\binary\out\index.js:8303:1089)
    at async Mon (C:\snapshot\continue\binary\out\index.js:8306:1072)
    at async Lon (C:\snapshot\continue\binary\out\index.js:8306:869) 
[2025-06-03T10:54:42] Error: HTTP 400 Bad Request from https://api.anthropic.com/v1/messages

{"type":"error","error":{"type":"invalid_request_error","message":"messages: at least one message is required"}} 
[2025-06-03T10:54:42] Error running handler for "streamDiffLines":  Error: HTTP 400 Bad Request from https://api.anthropic.com/v1/messages

{"type":"error","error":{"type":"invalid_request_error","message":"messages: at least one message is required"}}