Parse JSON module fails on Claude Haiku HTTP output — "Source is not valid JSON" Body:

Questions
,
1

:bullseye: What is your goal?

I have an automated content generation pipeline where module 87 calls the Anthropic Claude Haiku API via HTTP module. It rewrites text input and should return a JSON object with 4 string keys (script1, script2, script3, script4). Module 94 is a Parse JSON module that parses that output so the 4 values can be mapped to subsequent modules.

:thinking: What is the problem & what have you tried?

Module 94 consistently returns DataError: Source is not valid JSON even though the output bubble of module 87 shows what appears to be valid JSON.
What I have tried:

replace to strip backticks
Regex replace: /(^\w*\s*|\s*$)/g
Prefilling the Anthropic assistant message with { so Claude outputs clean JSON
Concatenating { using the & operator in a Set Variable module (module 102)
Specifying in the system prompt that JSON keys and values must use double quotes, and single quotes are only allowed inside string values

None of these approaches have solved the issue.

:clipboard: Error messages or input/output bundles

Error from module 94:
DataError
Source is not valid JSON.
Output from module 87 (content[1].text) appears as a JSON object with 4 keys in the output bubble, but module 94 refuses to parse it every time.

:camera_with_flash: Screenshots (scenario flow, module settings, errors)

Integration Google Sheets, Anthropic Claude, JSON.blueprint.json (913 KB)

3

Hey there,

Why are you using the http module and not the dedicated one? Cause with the dedicated module you can just force the response to be a valid JSON.

4

Welcome to the Make community!

If you still want to manually parse the JSON output from Claude, either:

  • Try my Extract JSON module from My Custom App, or
  • Provide more details about the failing output from Claude so we can advise if it is actually valid/invalid, and what could be done.

Please provide the Output bundle of the Claude module from the Scenario History, or by re-running the scenario.

Expand Instructions ◀

Click on the white speech bubbles on the top-right of each module and select “Download output (or input) bundles”.

A. Upload a Text File

Save each bundle contents in a plain text editor as a moduleNumber-output.txt file. Open the file to check if it has not added additional formatting or encoded the plain text.

  • You can upload files and images to this forum by clicking on the upload button:

    Uploading an attachment here will look like this:
    module1-input.txt (1.2 KB), module1-output.txt (3.4 KB)

B. Insert a Formatted Code Block

If you are unable to upload files on this forum, alternatively you can paste the bundles AND format them correctly with the “Preformatted Text” (code) button in the rich-text editor. Otherwise the forum software will change the content, making them invalid!

:warning: Formatting IS Important! :warning:

Here are some ways to provide text content in a way that it won’t be modified by the forum.

  • Method 1: Type code fence manually —
    Manually type three backticks ``` in a separate line before and after the content, like this,

    ```
text goes here
```

  • Method 2: Highlight the pasted content, then click the preformatted text/code button —

  • Method 3: Upload your file elsewhere and share the public link —
    This method is only advised for large files exceeding the forum upload limit.

Providing the Output bundle will allow others to replicate what is going on, especially if there are complex data structures (like nested arrays and collections) and data from external services. This helps us with answering your question with valid examples, like mapping raw variable names (instead of the label/display name).

This will allow others to better assist you. Thanks!

— @samliew