Relace instant apply failure - no support for completion

[IngLP]

Before submitting your bug report

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

Relevant environment info

- OS: macOS 15.4.1
- Continue version: 1.0.16
- IDE version: IntelliJ 2025.1.1.1
- Model:
- config:
  
models:
  - name: Relace Instant Apply
    provider: relace
    model: Instant-Apply
    apiKey: rlc-MS
    roles:
      - apply
    promptTemplates:
      apply: "{{{ new_code }}}"
  
  OR link to assistant in Continue hub:

Description

Ask whatever model to do a change to your code. Apply it using Relace Instant Apply (model config from continue hub). Apply fails with error "Relace provider does not support streaming completion."

To reproduce

No response

Log output

[tomasz-stefaniak]

@IngLP could you send a reproduction video? We are aware of some Relace issues but it's the first time I see one that's streaming related. A video would help me reproduce this locally.

[IngLP]

It's not a streaming problem, as far as I have understood. The problem is that in this file https://github.com/continuedev/continue/blob/432f36c080a50554c2a9648f4451d3d7c082aab1/packages/openai-adapters/src/apis/Relace.ts the completionStream method is called instead of the chatCompletionStream method, and the completionStream method is not implemented.

[OlhinAS]

Hi @tomasz-stefaniak!

OS Windows 11 24H2. JetBrains PyCharm Professional 2025.1.1.1 Continue 1.0.18 (EAP)

I have freshly installed Continue 1.0.18 for JetBrains EAP and got the same behavior when applying code block with Relace. My core log (no dev mode) is next:

[2025-05-24T22:58:37] Error: Relace provider does not support streaming completion. 
[2025-05-24T22:58:37] Error running handler for "streamDiffLines":  Error: Relace provider does not support streaming completion.
[2025-05-24T22:59:05] Error: Relace provider does not support streaming completion. 
[2025-05-24T22:59:05] Error running handler for "streamDiffLines":  Error: Relace provider does not support streaming completion.

[IngLP]

Hi @tomasz-stefaniak any updates on this? I am totally blocked in using Continue because I have no way to apply code changes! I tried

• gemini flash but it forgots closed square brackets
• openai mini but removes parts of my code (comments mostly) which should not be removed

I really don't know what to do!

[Patrick-Erichsen]

Could you try using the following in your config.yaml instead?

models:
  - uses: relace/instant-apply
    with:
      RELACE_API_KEY: ${{ secrets.RELACE_API_KEY }} ## Or if ~/.continue/config.yaml, just enter the API key

That will use the exact config from https://hub.continue.dev/relace/instant-apply?view=config

[IngLP]

I already tried it, same error.

[hnrhn]

I can also confirm that the error is not restricted to local setups using a config.yaml file. I get the same error when trying to use Relace in JetBrains both when using local config and when using the config directly from Hub. The error message exactly matches what's found in the file mentioned in https://github.com/continuedev/continue/issues/5644#issuecomment-2899292477

[PeterSarvas]

I encountered the same error message ("Relace provider does not support streaming completion") while using the VSCode extension.

The issue wasn't actually related to streaming support, but rather to the prompt format being sent to Relace. In my case, omitting this section from my config.yaml:

promptTemplates:
  apply: "{{{ new_code }}}"

caused the final message sent to Relace to have a conversational ChatML structure instead of the expected format.

Root cause: The function streamDiffLines (in core/edit/streamDiffLines.ts) calls constructEditPrompt, which returns a string. Later, in recursiveStream.ts (in core/edit/recursiveStream.ts), when the prompt is a string, it calls llm.streamComplete instead of llm.streamChat - but Relace expects the latter.

The error message is misleading since it suggests a streaming issue when it's actually a prompt format problem.

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This issue hasn't been updated in 90 days and will be closed after an additional 10 days without activity. If it's still important, please leave a comment and share any new information that would help us address the issue.

[github-actions[bot]]

This issue was closed because it wasn't updated for 10 days after being marked stale. If it's still important, please reopen + comment and we'll gladly take another look!

[shaked8634]

I suffer the same issue (IntelliJ IDEA 2025.2.3). core.log:

[2025-10-06T20:01:20] Error: Relace provider does not support streaming completion. [2025-10-06T20:01:20] Error running handler for "streamDiffLines": Error: Relace provider does not support streaming completion.